Leptocephali of the Ophichthid Genera <I>Ahlia

BULLETIN OF MARINE SCIENCE, 28(3): 442-486, 1978

LEPTOCEPHALI OF THE OPHICHTHID GENERA AHLIA, MYROPHIS, OPHICHTHUS, PISODONOPHIS, CALLECHELYS, LETHARCHUS, AND APTERICHTUS ON THE ATLANTIC CONTINENTAL SHELF OF THE UNITED STATES

Michael P. Fahay and Cinda L. Obenchain

ABSTRACT

Twelve leptocephali of the family Ophichthidae are described and j]]ustrated. Eleven types are specifically identified: Ahlia egmontis, Myrophis punetatus, M. platyrhynelllls, Ophiehthlls ophis, O. melanoporus, O. oeellatlls, O. gomesi, Pisodonophis crl/entifer, LetharchllS velifer, Apteriehtlls ansp, and A. kendalli. One type is assigned to the genus Callecllelys. Distribution maps showing capture locations on the Atlantic continental shelf are included for each type. Monthly length-frequencies are provided for ]0 of the more abundant types. Morphometric tables showing changes in bodily proportions with growth are included for nine types. The larval evidence supports McCosker's (1977) removing Echeills from the subfamily Myrophinae and reassigning it to the Ophichthinae. We discuss the generic identification of nominal Pisodonophis eruentifer, acknowledge the dissimilarity of that species to eastern Atlantic and Pacific Pisodonopllis, but question assigning P. crllentifer to Oplliehthus (McCosker, 1977). Western Atlantic P. eruentifer larvae are shown to be significantly different from Ophiehthus larvae. The degree of gut looping in ophichthid leptocephali is related to the amount and nature of pigmentation, and both larval characters are related to body elongation and fin reduction in adults. The leptocephali of A hlia have weakly swollen guts and scattered pigment patterns and the adults are relatively thick-bodied and retain a wide-based pectoral fin and high median fins. The leptocephali of Apterichtus have strongly looped guts and consolidated pigment patterns and the adults are relatively elongate and lack all fins. Genera between these extremes display a progression of both larval and adult characters.

Ophichthid leptocephali are the most com- vius (1763) to describe an eel larva later monly collected eel larvae along the Atlantic shown to be Conger conger. Western North continental shelf and are the most numerous Atlantic representatives of this nominal genus among the eight anguilliform families repre- include: L. caribbaeus Fowler, 1944; L. sented in the Sandy Hook Laboratory's ich- caudomaculatus Eigenmann and Kennedy, thyoplankton collection. Despite the large 1902; L. eigenmanni Lea, 1913; L. humilis number of species occurring in the western Stromman, 1896; L. morrisii Eigenmann and North Atlantic as adults (as many as 39) and Kennedy, 1902; and L. mucronatus Eigen- the relative abundance of leptocephali, the mann and Kennedy, 1902. All of these will early life-history stages of only two species be referred to ophichthid species in this have been described. Eldred (1966) de- paper. scribed the development of Myrophis punc- Eels of the family Ophichthidae are among tatus from the prelarva to the metamorphos- the most ecologically specialized of teleosts ing elver. Richardson (1974) described the and this specialization is reflected in a variety eggs and early larvae of Pisodonophis cruen- of leptocephalus larval stages. Ophichthid tifer. Several other ophichthids have been leptocephali are characterized by three or described and assigned to the nominal genus more loops or swellings along the gut which Leptocephalus, a name proposed by Grono- range from mildly thickened bulges (in the

442 FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 443 genus Ophichthus) to wildly festooned loops fied leptocephali should be weighed before (in the genus Apterichtus). Ventral pigment adding to the already confused literature. is usually concentrated on the thickenings or Favoring the practice are the following facts: loops of the gut. Pigment along the body (1) The leptocephali of most eel species be- midline ranges from a scattered pattern of cause of their pelagic mode of life are much small spots on each myoseptum (in the genus easier to collect than the adult stages, most Ophichthus) to a consolidation of pigment of which are by their nature secretive or into a few, bold, eye-sized blotches (in the burrowing forms which even if encountered genus Apterichtus). In the subfamily are difficult to contain within the meshes of Ophichthinae, the absence of a caudal fin in a net. In most cases then, if the identification adults begins in early metamorphosis with of larvae must await the assemblage of large the reduction of the larval finfold to a hard, numbers of juveniles and adults, the wait pointed tip. Members of the other subfamily could be a long one and the result might be (Myrophinae) retain the caudal fin but the the sequestering of larval collections to the leptocephali are recognizable by character- limbo of dusty collection shelves. (2) Lepto- istic short-based opisthonephroi located over cephali are widely diverse at the generic level the terminus of the gut and by pronounced while adults tend toward a morphological third gut swellings. conformity, related no doubt to the develop- Myrophines are further characterized by a ment of crevice-dwelling or sand-burrowing vent which migrates only slightly during habits (Castle, 1969). Thus, the study of metamorphosis. Thus, within a species, the larval types (named or not) might reflect number of preanal myomeres in the lepto- phylogenetic relationships not always ap- cephalus closely approximates the number of parent in the adults. (3) Most, if not all, preanal vertebrae in the adult. This condi- eel systematic work is based on adult ma- tion is found, in other anguiIIiforms, only in terial, but larval information may be an the family Moringuidae. Both moringuid and asset to workers in adult systematics as rein- myrophine larvae have short-based opistho- forcement material. The work on myc- nephroi associated with gut loops near the tophids (Moser and Ahlstrom, 1974) is an vent. Whether this opisthonephros-gut loop example of this application of larval studies. development is related to the nearly static (4) Larval information may be an asset (as vent position is unknown but it is tempting comparative data) to other workers in larval to speculate that such is the case. systematics. Because of the bizarre structure of lepto- Arguments against the practice include cephali and the relative ease with which the following: (1) As described leptocephali larvae are collected compared with the diffi- are finally linked to known adults, many culty in collecting adults, it has been the specific name changes will be required, since practice to publish descriptions of the more many "Leptocephalus" names antedate the distinctive types without knowledge of their adult names. (2) Most "species" of Lepto- specific identity. This has resulted in the ad- cephalus are actually groups of species, and dition to the literature of lettered or num- name changes may result in single species bered unknowns (i.e., "Species I," "Species being confused for a group. (3) The genus A," "Species 9a*") or species within the Leptocephalus simply has no validity as a nominal genus Leptocephalus. Castle (1969), generic grouping since it consists of a multi- in a thorough search of the literature, found tude of species, genera, and families. (4) descriptions of 70 distinct forms of eel larvae Assigning a distinctive larva to the genus designated by letters or numbers alone, and Leptocephalus pending a later linking to an more than 200 distinct forms assigned to adult species is at best a "temporary" ar- the genus Leptocephalus. rangement. As Bohlke and Smith (1968) The pros and cons of describing unidenti- have pointed out, this practice is tantamount 444 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

to deliberately proposing a name which will ultimately fall in synonymy. Since taxono- mists in other fields have long since discon- tinued this practice, it is difficult to defend its continued use in ichthyology. (5) Finally, we can find no reason to treat larval eels any differently than larval fishes of other groups, which are rarely, if ever, described

without the benefit of association with known ,. adults. 'll For the purposes of this paper, we follow a middle course. We present the description

of one unidentified larva in the hope that .. ,0 other workers may use the description as I '. I "t-'E ~\ supplementary material. We do not, how- \ ever, propose an invalid name for this form, ..• , . ,,\.iF nor do we wish to burden the literature \ .. , . ';,G unnecessarily with code-letters or numbers. ". Instead, we have elected to assign this unknown to a genus, a decision based primarily on similarities between it and known larvae. 35 METHODS ANDSOURCEOF MATERIAL Most leptocephali reported on were collected during 2 years of survey work aboard the R. V. DOLPHIN along the continental shelf from Cape Cod, Massachusetts to Palm Beach, Florida. Procedures during the first year are covered in detail in Clark et a1. 35 (1969) and during the second year in Clark ,I iBB et al. (1970). Collecting stations during those i 2 years are shown in Figure 1. Transects ycc with single-letter designations were sampled on eight cruises from December 1965 to De- cember 1966. Transects with double-letter designations were sampled on four seasonal cruises from May 1967 to February 1968. Supplemental, short-term cruises of the R. V. DOLPHIN and R. V. DELAWAREII have also yielded ophichthid larvae. Station locations and hydrographic conditions are contained in Fahay and Obenchain (un pub!.) which is available on request. We began our work on leptocephali by

~ Figure 1. Locations of plankton-collecting stations during two I-year surveys of the R. V. DOLPHIN. FAHAY AND OBENCHAIN: OPHICHTHJD LEPTOCEPHALI 445

analyzing morphometric and meristic char- Cosker (1977) but some were obtained acters in all eel families and later concen- from X-ray analysis of specimens we bor- trating our efforts on the family Ophichthi- rowed from various institutions. Information dae. Our measurements, counts, and terms on preanal vertebrae is meager but counts are follow Eldred (1966) except that we follow included if known. Castle (1965) in calling the renal artery Pigmentation is an important character and and renal-portal vein simply the last two one which is perhaps more useful when deal- vertical blood vessels. The term "tail" in ing with large numbers of ophichthid larvae this paper refers to that portion of the body than any other character. Myomere numbers posterior to thc vent. It was our purpose alone have little value above the specific throughout our analysis to use myomere level since there is so much overlap in counts counts only to verify our separation into spe- among genera. We feel that pigment in six cies, after the examination of other characters areas of the body is diagnostically important resulted in natural groupings of larval types. either at the generic or specific level: ( 1) Larval fishes have been identified by one along the midline of the body and tail in the of two methods. The first involves maintain- form of blotches or circular aggregations of ing living larvae in the laboratory, observing spots or on various myosepta in the form of their growth and metamorphosis, and pre- streaks or individual spots just ventral to serving specimens at various stages in their the midline; (2) deep, subcutaneous clumps development until a complete series is known. of pigment on the tail ventral to the midline; The second method involves assembling a (3) spots or series of spots along the anal complete series of growth stages from col- fin base; (4) spots or series of spots along lections at sea until the entire developmental the dorsal edge of the body; (5) pigment scries is represented. aggregations along the dorsal and ventral We believe a third method of examination surfaces of the gut, usually in association with and classification is productive when exam- each loop or swelling and sometimes between ining eel larvae. Since larval morphology the loops; and (6) pigment along the flank, and pigmentation do not persist into adult either between the midline and dorsal edge stages and since transforming juvenile stages of the body or midline and ventral edge of are virtually nonexistent in collections, we the body. subjectively identified the leptocephali de- In the species accounts which follow, each scribed in this paper after first grouping species is figured and described and a map "look-alikes" on the basis of structure of the is included to show locations of capture. gut (relative length and degree of looping), Morphometric tables showing changes in structure of the opisthonephros, position of bodily proportions with growth are included the liver, and extent and character of midline for nine species. Specimens included in the pigment. We then matched the myomere tables are divided into early larvae (with distributions of each group with vertebral counts of adults. We feel that if one is con- pointed snouts, undifferentiated nostrils, well- fronted with such a group of "Iook-alikes" developed fangs, and transparent bodies) and and meristic analysis reveals that the group transforming larvae (with blunt snouts, falls into three (for example) parts with separate nostrils, fangs often lost or reduced myomere counts of X, Y, and Z, and one has in number, and rounder, more opaque knowledge of an adult genus, three species bodies). Transforming ophichthines are of which have vertebral counts of X, Y, and further characterized by a loss of caudal fin Z, then one is justified in assuming that those rays and the development of a hard, pointed larvae belong to that genus. Vertebral counts caudal tip. Supplemental data (body lengths, of adults (where known) are listed in Table myomere counts, and hydrographic data as- 1. Most of the counts were taken from Mc- sociated with each catch) are combined for 446 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Table 1. Western North Atlantic ophichthid species with total and preanal vertebral counts where known. Abbreviations of institutions are as follows: SIO = Scripps Institution of Oceanography; USNM = United States National Museum; MCZ = Museum of Comparative Zoology, Harvard University; SHML = Sandy Hook Marine Laboratory.

Vertebrae Species Total Preanal Source Ahlia egmontis 152 McCosker, 1977 Ap/atoplzis clzau/iodus 110-111 McCosker, 1977 Aprognathodon p/atyventris 150-155 98-99 McCosker, 1977 & SIO 68-393 Apterichtus ansp 123-132 53-58(*) Bohlke, 1968 130 50 SHML 000027 A. kendalli 137-144 61-65(*) Bohlke, 1968 Bascanichtlzys paulensis 191 McCosker, 1977 B. teres 181-184 Blache and Cadenat, 1971 B. scuticaris Callechelys bilinearis 162 McCosker and Rosenblatt, 1972 161-163 89 McCosker, 1977 & SIO 70-376 C. holoehromus 166 McCosker, 1977 C. muraena 141-144 McCosker, 1977 & McCosker and Rosenblatt, 1972 C. perryae 178-179 McCosker and Rosenblatt, 1972 & Blache and Cadenat, 1971 C. springeri 170 McCosker and Rosenblatt, 1972 166-170 McCosker, 1977 Cara/ophia /oxoehila 139-145 68 McCosker, 1977 & SIO (uncal.) Echioplzis illtertilletus 134-143 Blache, 1971 E. mordax 130 McCosker, 1977 E. punetifer Gordiiehthyst irretitus 225 Orton, 1962 Iehthyapus ophioneus 132-137 McCosker, 1977 Letharchus velifer,* 135-143 McCosker, 1974 Myric/ltlzys aeuminatus M.oeulatus 170-171 McCosker, 1977 Myrophis punctatus 138-145 48-53 Eldred, 1966 M. platyrhynelzus 138-147 45-48 D. G. Smith (pers. comm.) 138-145 44-49 David M. Dean (pers. comm.) Ophichthus gomesi 141 Orton, 1962 & Jordan and Davis, 1892 O. guttifer 136 USNM 32647 (holotype) O. lIIe/anoporus 177-186 Kanazawa, 1963 O. ocellatus 134 Jordan and Davis, 1892 O. magniocu/is O.ophis 161-170 Blache and Saldanha, 1972 O. parilis O. retropillnis 129 USNM 38054 O. ascensionis O. spinicauda 143 60 MCZ 32788 O. puncticeps Pisodonophis cruentifer§ 145-152 61-62 Richardson, 1974 & SHML (uncal.) Pseudolllyrophis nimius 212-216 72 Bohlke, 1960 & McCosker, 1977 Quassirelllus productus 132-136 65-68 USNM 170563 (holotype) USNM 170564 (paratypes) • Number of preanal lateral line pores. t Problematical genus-familial affinities in doubt (Rosenblatt and McCosker, 1970). Referred to Ophichthidae by Me- Cosker (1977). '* Total vertebrae in holotype reported to be 149 in McCosker, 1973, corrected to 139 in McCosker 1974 and 1977. § Referred to Ophichtlll/s by McCosker (1977). See P. cmen/ifer discussion. • FAHA Y AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 447

all species in a table which is available on request (Fahay and Obenchain, unpubl.). Nomenclature, including the use of the subfamilial name Myrophinae, follows Mc- Cosker (1977) but our order of presenting the genera differs from his classification. Our sequence is dependent on certain fea- '"r- o tures (i.e., pigment and gut structure) and '" proceeds from forms with scattered pigment 00 o and mildly-swollen guts to forms with con- r- solidated pigment and strongly-looped guts. 00 Specimens have been deposited III the larval fish collection at the Sandy Hook '" Laboratory.

SPECIES ACCOUNTS '" Subfamily Myrophinae Leptocephali of the Myrophinae differ from other ophichthids in the retention of the larval caudal finfold·, a precursor of a well-developed caudal fin in adults. The gut is weakly swollen in three to six places, and the third swelling IS the most pronounced. The opisthonephros is a twin- peaked, short-based structure located over the terminus of the gut. Vent position relative to myomere-vertebra number changes '";:!; •...•00 little during metamorphosis, thus the number of preanal myomeres in larvae closely approximates the number of preanal vertebrae in adults. Midline pigmentation consists of various scattered patterns of dashes on the myosepta. Pigment on specific parts of the body varies with the species. Counts of preanal and total myomeres in the three species are summarized in Table 2. o....•

'"..., Ahlia egmontis (Jordan) (Figs. 2, 3 and 4; Tables 2 and 3) Diagnosis.-Myrophine larva with 152 to o ..., 165 myomeres characterized by pigment spots along dorsal edge of body, single pigment spot at base of each anal ray, and dashes on nearly every myoseptum. Description.-44 specimens examined, 56.0 to 82.0 mm TL; myomeres 152-165; preanal myomeres 65-73; anterior margin of 448 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Table 3. Meristics and body proportions (expressed as percentage of total length) of selected early larval and tranforming (below dashed line) Ahlia egmontis

Subcu- Myomeres Teeth taneous Caudal Size Predorsal Preanal Tail Fin (mm TL) Lcngth/TL Length/TL Tolal Predorsal Preanal Maxilla Mandible Spots Rays

56.0 52 53 155 70 72 I-V-4 I-V-3 7 5 61.5 52 53 159 68 70 I-IV-4 I-V-O 6 7 62.0 52 53 158 67 70 I-V-4 1-1ll-4 7 5 67.3 51 52 158 68 71 I-1ll-2 I-IV-2 7 5 71.0 49 50 159 67 71 I-IV-3 I-V-3 5 5 71.1 49 50 159 70 73 I-IV-3 I-IV-3 4 6 72.0 49 50 161 68 71 I-V-6 I-V-3 6 5 73.4 47 48 164 67 71 I-V-3 1-V-2 6 D 73.8 49 50 161 68 70 I-V-3 I-V-3 7 6 74.0 45 45 155 63 65 1-111-5* I-VI-O 4 7 75.0 48 48 163 67 70 I-V-4 I-IV-2 6 6 75.0 52 53 163 68 71 l-IV-4 1-IV-2 7 D 75.0 48 49 156 69 72 I-V-3 I-V-2 7 6 75.5 48 49 163 65 68 I-V-4 I-VI-3 6 6 75.5 49 50 ]60 68 71 I-V-3 I-V-2 7 5 76.0 47 47 154 67 69 0-IV-3 I-IV-2 7 6 76.2 48 49 159 68 71 I-IV-3 I-V-3 7 6 77.0 48 49 158 66 69 0-IV-3 I-V-2 5 D 77.0 49 50 161 67 69 I-V-3 l-V-3 5 6 77.5 49 50 157 67 68 I-IV-4 I-IV-4 D 6 77.7 48 49 158 67 70 I-V-3 I-V-2 6 6 78.0 50 51 160 70 71 I-V-4 I-IV-2 6 5 79.0 49 50 165 69 72 I-V-3 I-VI-2 6 6 79.7 49 49 152 69 70 I-IV-6 I-V-3 6 6 82.0 48 48 155 68 70 I-IV-6 I-V-3 7 6

76.0 46 47 158 65 68 1-111-0* I-IV-2 4 5 75.5 48 49 157 69 72 D D 4 6 75.4 48 49 158 67 70 I-IV-2* I-V-O 4 6 75.2 48 49 159 65 71 0-IV-2 I-V-2 4 5 73.2 49 49 164 67 69 NONE NONE 4 6 69.0 49 49 160 67 70 I-IV-7'" I-V-2 5 5 68.0 49 49 162 68 70 1-11I-2* I-IV-2 5 5 66.0 49 50 159 64 68 0-11-3 I-lll-O 4 6 60.5 50 50 159 67 70 0-11I-2 I-V-O 5 7 • = broken fang; D = damaged. liver at myomere 13 to 18; posterior margin formula 0 to 1 + II to V + 0 to 7; relative of liver at myomere 21 to 32; first major preanal length ranges from 53% to 47% TL; artery joins aorta at myomere 16 to 24; relative predorsallength ranges from 52% to last two vertical blood vessels join aorta at 46% TL (Table 3). myomere 62-66 and myomere 68-71 respectively; dorsal fin origin (difficult to Pigmentation.-Nearly every myoseptum discern) at myomere 63 to 70; gut swollen pigmented with series of dashes just ventral III four (rarely five or six) places, first to midline; four to scven subcutaneous spots swelling at about myomere 17, third swelling below midline on tail; gut pigmented on pronounced, fourth (and fifth and sixth, if dorsal and ventral surfaces at level of each present) low and indistinct; opisthonephros swelling and on dorsal surface near vent; a short, located over teminus of gut; with two series of spots along dorsal edge of body; peaks on dorsal surface; maxillary dental anal base pigmented with single spot at base FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 449

. __ -'o'"",'.-.-~:'..•• -'~"' , .-~,-- •• w.

":."'..,

Ill/llf! rrf(t'(ftfft{!f..{rr;mll ---- ..- •.....•.•..•... --

. ' ' . , . , . =O;~';;~~'.;~\ ...."7:;;~. '. .\/ ..

~~~~~i~..:~::;~},~%.~ ••• c Figure 2. Ahlia egmontis: a-leptocephalus 78.0 mm TL; b-head of specimen 62.0 mm TL; c-midsection of body of specimen 74.0 mm TL.

of each ray; few small spots in gular area and dal and anal fins, and most myosepta with on snout. light streaks under the midline. Castle (1969) refers L. humilis to the Discussion.-Leptocephalus humilis Str6m- Congridae and suggests it belongs in the man, as described by Eigenmann and Ken- genus Ariosoma. The short gut seems to us nedy (1902), is referable to Ahlia egmontis. to present an obstacle to this opinion. Also, The 75, 76, 78, and 85 mm specimens de- at least in the Eigenmann and Kennedy speci- scribed by Eigenmann and Kennedy (1902) mens, the gut is definitely swollen in at least have 68 to 71 preanal myomeres and 157 two places. Congrid leptocephali have simple to 162 total myomeres, pigment spots on the (unswollen) guts which usually extend 75% dorsal surface of the gut, pigment along dor- of the total length or more. sal edge of the body, and spots along bases of Ahlia egmontis leptocephali were taken dorsal, caudal and anal fins, and myosepta from Cape Hatteras to Palm Beach (Fig. 3) with streaks except near head. The specimen during all seasons (Fig. 4). All were taken illustrated has a prominent gut swelling in in areas where the surface temperature was the approximate area of the third swelling in above 20°C and as high as 28.7°C. our A. egmontis specimens and also has a The lack of specimens smaller than 56.0 distinct swelling at the terminus of the gut, mm is puzzling. We believe the pigmentation which corresponds to the location of the in this species is distinctive enough to pre- characteristic opisthonephros in myrophines. clude its being confused for any other ophich- Finally, the caudal fin is retained which thid larva and can only conclude that smaller would not be the case in ophichthines at such specimens only occur outside the area which a large size. we sampled, probably near the Florida Keys, The original description of L. humilis in the Caribbean, or offshore of the conti- (Str6mman, 1896), based on specimens 70 nental shelf. Cohen and Dean (1970) re- and 88 mm TL, adds the following: dorsal ported the capture of 81 maturing adults fin origin immediately anterior to the vent, of this species, all of which were actively caudal present, preanal length subequal to moving offshore from the coast of Honduras. 50% of the total length, a row of spots along Enlarged eyes in these specimens indicated ventral edge of gut, pigment along dorsal a spawning migration toward deep water in edge of body and along bases of dorsal, cau- the Caribbean. Although this report does 450 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

------". -~ JANUARY

~'4J 73"~lf n=l 40.- 61

W fEBRUARY n=4 ,,' ~I J

34' ;I APRIL 61 n=l

lJ.J ~ 0:::« -' JULY 0"'- a:: n=l w 61 ::2CD ~~: z::l AUGUST 0 n=6 :1 ~ \ .-r--,---, c IO:IU JIO 10 -

78" /2r 5

DECEMBER 6\ n=1 55.0- 60.0- 65.0- 70.0- 75.0- 80.0- ,,,/fI' 59.9 64.9 69.9 74.9 79.9 84.9

51ZE GROOP5 (mm TU

Figure 4. Length·frequencies of Ahlia egmontis leptocephali.

Figure 3. Occurrences of Ahlia egmontis, Myr- ophis punctatus and M. platyrhynchus leptocephali not preclude the possibility of spawning off and elvers. Each 6. represents the capture location the Florida coast, it does suggest that this of one A. egmontis leptocephalus; each 0 repre- species spawns beyond the continental shelf. sents the capture location of one M. puncta/us Ahlia egmontis larvae apparently delay leptocephalus; each E represents the capture loca- metamorphosis until suitable environmental tion of one M. punctatus elver; each • represents the capture location of one M. platyrhynchus conditions are encountered. We assume that leptocephalus. metamorphosis occurs at about 80.0 mm FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 451

-----. a , '~i'-~'?'-""""

,/llft/II/'hllllfl'"/''''''IJI/,,,,,,,I''''''''01l,,,,,,,m/,,''''''''//1''''II,fl/{lhl

c Figure 5. Myrophis punctatus: a-leptocephalus 63.8 mm TL; b-head of specimen 58.3 mm TL; c- midsection of body of specimen 60.2 mm TL.

(which is the approximate maximum size at- of gut, with two peaks on dorsal surface; tained by Myrophis punctatus larvae before maxillary dental formula 0 to 1 + III to transforming) and we caught larvae greater VIII + 3 to 7; relative preanal length de- than 70.0 mm the year-round (Fig. 4). Two creases from 69% TL at 23.8 mm to 44% larvae (79.9 and 81.8 mm) caught off the TL at 78.2 mm. New Jersey coast and south of Martha's Vineyard provide further evidence that, lack- Pigmentation.-Myosepta sporadically pig- ing a suitable environment in which to meta- mented along midline; no subcutaneous spots morphose, leptocephali will continue to drift below midline on tail; gut pigmented on at some maximum larval size. ventral surface of first and second bulges, on dorsal and ventral surfaces of third bulge, Myrophis punctatus Liitken and intermittently along straight portions of (Figs. 3, 5 and 6; Tables 2 and 5) intestine. Anal base pigment changes with growth: at about 40 mm, linear clusters of Diagnosis.-Myrophine larva with 138 to large spots appear along transparent band of 150 myomeres characterized by a lack of body wall between myomeres and anal fin subcutaneous spots below midline on tail, base; from about 50.0 mm until metamor- and small spot at base of each anal ray in phosis, these linear clusters are accompanied addition to linear clusters of spots along the by a row of smaller spots, one occurring at body wall between myomeres and anal fin base of each anal ray (Fig. 5c). Few spots base. in gular region and on snout. Description.-198 specimens examined, 22.5 Literature.-Eldred (1966) described the to 78.2 mm TL; myomeres 138-150; preanal development of M. punctatus from the early myomeres 52-63; anterior margin of liver larval to elver stage. Meristics and morpho- at myomere 10-16; posterior margin of liver metries in her description do not differ from at myomere 19-27; first major artery joins our observations. aorta at myomere 13-20; last two vertical blood vessels join aorta at myomere 48-54 Discussion.- These larvae agree in almost all and myomere 54-60 respectively; dorsal fin details with larval Myrophis plumbeus from origin at myomere 30-37; gut swollen in the eastern South Atlantic (Blache, 1968), three places, third swelling most pronounced; most significantly in the lack of subcutaneous opisthonephros short, located over terminus spots below the midline on the tail, and lack 452 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

mere, no deep (i.e., subcutaneous) lateral pigment; no dorsal pigment; 145 to 151 - - myomeres; 56 to 60 preanal rnyomeres. Capture locations for M. punctatus lepto- NOVEMBER 13 n,46 cephali are included in Figure 3. Eldred 10 (1966) reported M. punctatus larval occurrences in the Gulf of Mexico and Jupiter and St. Lucie inlets. She concluded that DECEMBER n= I this species spawns offshore in waters south o I - of Florida, the developing leptocephali drift

~l JANUARY north, and the elvers move inshore in late ",130 38 winter and early spring. The monthly length- frequencies we observed (Fig. 6) substanti- 28 ate Eldred's conclusions regarding winter " growth. Our captures of small larvae (about 23 to 40 mm) off the coast of North Carolina indicate spawning also occurs in the South FE~~~ARY Atlantic Bight. ~ I - Eldred (1966) reported that elvers were MARCH' APRIL & I ".J abundant in March but were not taken after A~~UST -- May. We caught one elver (54.0 mm) in &I ELVER August 1972 just south of Cape Lookout, 20·0- no· 30.0- 3~O· 40.0- 45.0- 50.0- 55.0· eo.o- es.o· 70.0· 75,0- 24-" :N,V 34,; 3lUl 44,IiI 4119 -54,; 59.; e4,g (lg,; 74,; 7;,; N.C. in a neuston net. Elvers apparently SIZE !;ROUPS (mmTU cease their planktonic existence between Figure 6. Length-frequencies of Myrophis pUIlC- March and May and then presumably burrow talus leptocephali. into the bottom (Springer and Woodburn, 1960). Our neuston-net record indicates of spots on the dorsal surface of the opistho- that elvers later in the year occasionally are nephros. Blache (1963) also cites the fol- present at the surface, as has been reported lowing characters in his "type lOa" (= M. for adults (Bohlke and Chaplin, 1968; plum be us): dorsal fin origin at 26th myo- Fahay, 1975). Our capture of an early

Figure 7. Myrop/lis platyrhYllchus: a-leptocephalus 61.6 mm TL; b-head of same specimen; c-midsection of body of same specimen. FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 453

Table 4. Meristics and body proportions (expressed as percentage of total length) of four larval Myroplris plaryrirynclllls

Subeu- Myomeres Teeth taneous Caudal Size Predorsal Preanal Tail Fin (mm TL) Length/TL Length/TL Total Predorsal Preanal Maxilla Mandible Spots Rays ~-- ---~ 29.4 28 65 142 21 51 l-UI-3 l-UI-3 4+ NONE 32.2 D 62 147 D 56 I-UI-6 l-I1I-2 5+ D 59.0 D 43 144 D 52 l-IV-5 I-V-4 5+ D 61.6 22 47 140 21 53 I-V-5>1< I-VI-2* 5+ 5

• = broken fang; D = danlaged; + = plus one spot over opisthonephros. larva (45.3 mm TL, with a single, undif- liver at myomere 21-29; first major artery ferentiated nasal capsule) in April east of joins aorta at myomere 13-20; last two verti- Cape Hatteras indicates that spawning off cal blood vessels join aorta at myomere 46- the South Atlantic coast may continue after 49 and myomere 50-55 respectively; dorsal spawning has ended in areas south of Florida. fin origin at myomere 21; gut swollen in We have also examined a leptocephalus four places, third swelling most pronounced, caught in the Chesapeake Bay by the Natural fourth low and indistinct; opisthonephros Resources Institute of the University of short, located over terminus of gut, with Maryland in January 1974. Apparently, two peaks on dorsal surface; maxillary den- larvae spawned in the South Atlantic Bight tal formula 1 + III to V + 3 to 6; relative occasionally drift past Cape Hatteras and preanal length decreases from 65% TL at enter inshore waters of the Middle Atlantic 29.4 mm to 47% TL at 61.6 mm; relative Bight. It is doubtful, however, that these predorsal length ranges from 28% to 22% waifs successfully undergo metamorphosis TL (Table 4). since adults have not been recorded north of North Carolina (Briggs, 1958). Pigmentation.-Sporadic pigment on myo- Eldred (1966) found, in four collecting septa along midline increasing with growth. At 29.4 mm, one spot on myoseptum at level areas, from 82% to 100% of her larvae and of fourth gut swelling; at 32.0 mm, two addi- elvers at night and from 77% to 100% at tional myosepta pigmented; at 59.0 and the surface. We found no such diel or depth 61.6 mm, myosepta pigmented as in illustra- preferences in the larvae and elvers we tion; gut pigmented on dorsal surface of sec- caught. ond, third, and fourth swellings and ventral surface of first, second, and third swellings; Myrophis platyrhynchus Breder spots present on dorsal surface of terminus (Figs. 3 and 7; Tables 2, 4 and 5) of gut and on dorsal surface of opistho- Diagnosis.-Myrophine larva with 140 to nephros (Fig. 7c); few spots on intestine 147 myomeres characterized by six subcu- between gular area and first swelling; four taneous spots below midline (the first at to five subcutaneous spots below midline on level of opisthonephros, second through tail; additional subcutaneous spot at level of sixth on tail), and anal base pigmented with opisthonephros; single spot at base of each spot at base of each ray. anal ray, not evident in smaller specimens (Fig. 7c). Few spots in gular region and Description.-Four specimens examined, on snout. 29.4 to 61.6 mm TL; myomeres 140-147; preanal myomeres 51-56; anterior margin of Discussion.-Myrophis platyrhynchus cap- liver at myomere 9-13; posterior margin of ture locations are included in Figure 3. We 454 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Table 5. Comparison of larval pigmentation in two species of Myropflis

Nature of Pigment Area of Body Myrophis punctatus MyroplJis pilltyrhynchus

Below midline on tail No pigment Subcutaneous spots present

Dorsal surface of No pigment Several spots opisthonephros

Anal fin base Spot at base of each ray Spot at base of each ray

Transparent body wall Linear clusters of No pigment between anal fin spots separated by base and myomeres unpigmented gaps

captured two of these larvae in the summer, to a bold, consolidated pattern of prominent when no M. punctatus leptocephali were spots in Apterichtus. taken, one in the fall and one in the winter. McCosker (1977) removed Echelus from These larvae are similar to larval M. the subfamily Myrophinae and aligned it punctatus in shape of opisthonephros, re- with the Ophichthinae. His opinion was tention of caudal fin, nature of gut swellings, based on certain osteological and external and myomere counts (although the preanal characters of adults. We feel his opinion is and predorsal counts are slightly lower than further substantiated by Blache's (1968) the counts in M. punctatus). Were it not for descriptions of larval Echelus myrus which the pigmentation differences (Table 5) the closely approximate our larval Ophichthus two types would be indistinguishable. in character of midline pigment and which lack characters found in larval myrophines, Subfamily Ophichthinae such as the prominent third gut swelling and the characteristic opisthonephros located Older leptocephali of the Ophichthinae over the vent. lose the caudal finfold as they approach metamorphosis and replace it with a hard, Genus Ophichthus pointed caudal tip.1 The genera Ophichthus and Apterichtus represent the extremes in Larval Ophichthus are the most commonly development of larval characters while the collected ophichthid leptocephali along the other genera display intermediate develop- Atlantic continental shelf. Specimens in the ment. The gut is relatively long and weakly genus account for 68% of all ophichthids in swollen in Ophichthus, shorter and strongly our collection. The leptocephali in the genus looped in Apterichtus. The opisthonephros Ophichthus form a cohesive group which in all ophichthine genera is long and slender, share most characters. Distinguishing dif- in contrast to the condition found in myro- ferences within the group are number of phines. The vent migrates relative to somite myomeres, number of subcutaneous spots number, thus the number of preanal myo- below midline on the tail, and nature of anal meres in early larvae does not closely corre- base pigment. spond to the number of preanal vertebrae in We have several reasons for assigning adults. Pigment varies from a uniform, scat- the following four larval types to the genus tered pattern of midline dashes in Ophichthus Ophichthus. Comparisons of our larvae with published descriptions of Ophichthus spp.

1An exception to this generalization is Echelus which (Castle, 1965) from Australian waters sug- retains a caudal fin but has been aligned with the Ophichthinae (McCosker, 1977). gest that our larvae share generic characters. FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 455

Most ophichthid genera in the western North three types which we have tentatively referred Atlantic are represented by 1 to 3 species to Ophichthus but which we have not in- while Ophichthus is known to include at cluded in the present paper. These three least 4 and as many as 11 species. Four of unnamed larval types may represent Ophich- the species (0. ophis, O. melanoporus, O. thus species which await discovery or species ocellatus, and O. gomesi) are definitely sepa- native to waters outside the area we sampled rable by vertebral counts which coincide with and for which we have been unable to obtain the myomere ranges in four of our larvae. vertebral counts. The status of three of the remaining spe- Ophichthus larvae are characterized by a cies of Ophichthus is unclear. Randall and relatively long body where the depth equals Robins (1966) referred Acanthenchelys about Yir, the length. The gut is long and spinicauda Norman to the genus Ophichthus weakly swollen in 7 to 9 places. Often, the and referred O. zonatus Rivero to the syn- weak gut swellings are only noticeable be- onymy of O. spinicauda. Cervigon (1966) cause of the clusters of pigment spots which cites the range of this species as Cuba, accompany them. Pigment also includes an Tobago, and the northern coast of Venezuela. evenly scattered pattern of streaks just ven- It is entirely conceivable, therefore, that tral to the midline on each myoseptum, com- larvae may drift into continental shelf waters mencing at about myomere 20. Anterior to of the United States from more southern myomere 20, some myosepta may be unpig- waters. mented. There are two to five subcutaneous Schroeder (1941) referred O. guttiter Bean spots below the midline on the tail in all and Dresel to the synonymy of o. ocellatus species, although these spots are faint or while Randall and Robins (1966) referred lacking in leptocephali of o. melanoporus both O. guttiter and O. retropinnis Eigen- larger than about 55.0 mm. Preanal and total mann to the synonymy of o. ocellatus. Gins- myomere counts in our specimens are sum- burg (1951), however, in his study of the marized in Tables 6 and 7. eels of the Gulf of Mexico recognized O. Our collection also includes several larval ocellatus, O. guttiter, and o. retropinnis as congrids with pigment patterns similar to distinct species. McCosker (1977) recog- Ophichthus larvae. Congrid larvae, however, nized O. retropinnis but did not mention have simple guts (without swellings) which O. ocellatus or O. guttiter in his general ac- usually extend 75% or more of the total count (but did include O. ocellatus in a table length. Gut pigment is evenly scattered, not of vertebral counts). consolidated into clumps as it is in Ophich- McCosker (1977) also added the follow- thus spp. Congrid larvae also lack subcu- ing western Atlantic species to Ophichthus: taneous spots below the midline on the tail. o. ascensionis Studer; O. magnioculis Kaup; O. parilis Richardson; and O. puncticeps aphichthus ophis (Linnaeus) (Kaup). We have been unable to find ver- (Figs. 8, 9 and 10; Tables 6, 7 and 8) terbral counts for these species. Finally, Diagnosis.-Ophichthus larva with 158 to McCosker (1977) referred the western At- 170 myomeres characterized by two or three lantic species Pisodonophis cruentiter to subcutaneous spots below midline on tail, Ophichthus, an opinion which we discuss in and anal base pigmented with linear clusters our section on P. cruentiter larvae. of spots separated by unpigmented gaps. The purpose of this paper is not to resolve the taxonomic questions in the genus Ophich- Description.-44 specimens examined, 46.0 thus but to present evidence that at least four to 101.0 mm TL; myomeres 158-170; pre- distinct larval types referable to that genus anal myomeres 89-97; anterior margin of are present in Atlantic coastal waters of the liver at myomere 11-14; posterior margin United States. Our collection also includes of liver at myomere 22-28; first major artery 456 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

0 .,., 0 ~ l'l

00 co :! 0 ~ '

0 co 00 :!'" ....• '"~ \0

l'l 0\ l'l

•.•••0 :!'" ~ \0 ~'" '" § M QO ••••• ....• 0 on ;:!; '<1"••.•.. ; E" ;l '; V) •..... '. •.. ~ ~ r-- '" 8 8 '" 00 ~ 00 0 <;l ;>. \D Q 8 c:: <::> .!2 ., c.. .!2 ., c.. a ~.C:; <::> ~.i:; <::> .D ., s:: a s:: .s", .D ~ '" .::; '.5 '- ~ ::gE -<:: .s "E <::> ~-c..'" '5 <.l <::> c.. '" <::> 00 <::> E c 00 c '"E (5 .," ., ., ., (5'" ., ., ., ., ;::! ;::! ;::! :::l ::s ::s ::s ::s ..0 -;S-;S -s'S "S'5 'S 'S ...::::.....:::: ....:::: ...::: r-: ~-<:: -<:: •.. .~.~ .~,~ •.. .~ "t ~ •..•.....•...... ::...::: ~ ~~ -<:: :.E

Figure 8. Ophichthus aphis: a-leptocephalus 90.3 mm TL; b-head of specimen 69.0 mm TL. joins aorta at myomere 13-26; last two verti- Stream probably plays an important part in cal blood vessels join aorta at myomere transporting larvae to Bermuda waters where 85-95 and myomere 87-98 respectively; the transforming juveniles are able to find dorsal fin origin at about level of first gut suitable environmental conditions. The spe- swelling (myomere 11-16); gut with seven cies has not been recorded from continental swellings, none distinct; opisthonephros shelf waters north of Cape Kennedy. Pos- long, lying along dorsal surface of gut, the sibly, the incursion of cold water in the winter last two vertical blood vessels relatively far months prevents the establishment of adults apart; maxillary dental formula 0 to 1 + II in the area. to VIII + 5 to 12; relative preanal length decreases from 72% TL at 46.0 mm to 63% Ophichthus melanoporus Kanazawa TL at 101.0 rum; relative predorsal length (Figs. 9, 11 and 12; Tables 6, 7 and 9) decreases from 12% TL at 49.0 mm to 8% Diagnosis.-Ophichthus larva with 175 to TL at 101.0 mm (Table 8). 190 myomeres characterized by four faint Pigmentation.-Every myoseptum (except subcutaneous spots below midline on tail several of anterior few) with dashes just ven- (disappearing in larger larvae), and anal tral to midline; gut pigmented on dorsal base pigmented with single spot at base of and ventral surfaces, concentrated on swell- each ray. ings; gut pigment becoming more sparse in Description.-45 specimens examined, 24.0 larvae greater than about 75.0 mm; three to 92.0 mm TL; myomeres 175-190; pre- subcutaneous spots below midline on tail, anal myomeres 101-110; anterior margin of reduced to two spots during transformation; liver at myomere 11-14; posterior margin of anal base pigmented with linear clusters of liver at myomere 22-29; first major artery spots separated by unpigmented gaps; few joins aorta at myomere 7-14; last two vertical spots in gular area. blood vessels join aorta at myomere 97-103 Discussion.-Catch locations are shown in and myomere 100-109 respectively; dorsal Figure 9. The monthly length-frequencies fin origin at myomere 12-17; gut very weakly (Fig. 10) indicate spawning occurs in spring swollen, the first two swellings (associated or early summer and the larvae grow about with liver) noticeable, the remaining five not 25 mm over the 2-month period, August to apparent except for aggregations of pigment October. spots which attend each; opisthonephros The recorded range of this species is from long, lying along dorsal surface of gut, the Brazil to southern Florida and Bermuda last two vertical blood vessels relatively far (Bohlke and Robins, 1959). The Gulf apart; maxillary dental formula 0 to 1 + III 458 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

w ,I A~5,UST re' ~o_~--....-__-~ _ I:"I OCTOBER.~__ ••••• _ 450, 500· 550 600· 650 7iJO 750 HOQ tOO 000 9:10 W:I[) ,jgQ 549 5Qq 6-4Q 6~q 149 1'j'l H4<) Mil 'l4C1 IN/) lI'-H " ,,' Figure ]0. Length-frequencies of OphichrllUs ophis leptocephali.

". to VII + 4 to 10; relative preanal length decreases from 83% TL at 24.0 mm to 64% TL at 92.0 nun; relative predorsallength decreases from 18% TL at 46.3 mm to 10% TL at 92.0 mm (Table 9). Pigmentation.-Every myoseptum (except several of anterior few) with dashes just ventral to midline; gut sparsely pigmented on 33" dorsal and ventral surfaces; dorsal gut pigment concentrated over seven swellings; one to four subcutaneous spots below midline on J • a• tail, becoming broken up and faint at 55.0 mm and disappearing in larvae over 78.0 mm; anal base pigmented with single spot at base of each ray; few spots in gular area. Discussion.-Catch locations are shown in 31· Figure 9, and monthly length-frequencies in Figure 12. Kanazawa's (1963) original description was based on five adult specimens captured in 461.5 m west of Andros Island, Bahamas. The only record in United States OS' waters was under unusual circumstances at Marineland, Fla. (Gilbert, 1968), where it was apparent that several deepwater species ,.. (including O. melanoporus) had moved in- ". shore in response to unknown stimuli. Our captures indicate that the larvae of this deepwater species occur inshore. After metamorphosis, the juveniles presumably migrate toward the edge of the shelf, for, except for ------.. ------the Marineland specimens, adults have not Figure 9. Occurrences of Ophichthus ophis and O. been recorded in less than 461.5 m me/alloporus leptocephali. Each 6 represents the Kanazawa (1963) reported that this spe- capture location of one O. ophis leptocephalus; each • represents the capture location of one O. cies is very close to O. hispanus from the me/alloporus leptocephalus. Mediterranean Sea. In a description of O. FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 459

Table 8. Meristics and body proportions (expressed as percentage of total length) of larval and transforming (below dashed line) Ophicllthus aphis

-- .------Subeu- Myomeres Teeth taneous Size Predorsal Preanal Tail Caudal (mmTL) Length/TL Lcngth/TL Total Predorsal Preanal Maxilla Mandible Spots Tip

46.0 D 72 166 D 94 I-V-6 I-V-7 3 6 rays 49.0 12 71 164 14 92 I-IV-7 I-V-4 3 5 rays 51.0 11 71 165 13 97 I-V-7 I-V-5 3 6 rays 55.0 D 71 161 D 92 I-V-6 I-IV-5 3 6 rays 64.0 12 70 163 14 91 I-V-5 I-V-4 3 5 rays 66.0 12 69 165 16 96 I-VI-5 I-V-4 3 5 rays 69.0 II 68 170 14 95 I-V-7 I-VI-3 3 6 rays 70.0 II 67 169 13 96 I-V-9 I-VI-3 3 6 rays 71.0 9 67 169 13 96 I-V-7 I-V-4 3 rudimentary rays 71.0 10 67 158 13 89 I-IV-S I-VI-5 3 rudimentary rays 72.0 9 67 159 13 92 I-V-S I-IV-6 3 rudimentary rays 73.0 9 66 164 12 95 I-IV-9 I-V-4 3 rudimentary rays 74.0 9 67 162 13 92 I-V-7 I-VlI-4 3 rudimentary rays 74.0 9 66 159 13 90 I-V-7 I-V-4 3 rudimentary rays 74.0 9 66 159 12 90 I-V-7 I-V-4 3 rudimentary rays 74.0 9 66 164 12 96 I-IV-lO I-V-6 3 rudimentary rays 75.0 8 64 165 12 92 I-VIII-5 I-VI-4 3 hard tip 76.0 8 65 164 12 95 I-IV-9 I-V-4 3 hard tip 78.0 8 64 162 12 93 I-V-8 I-V-5 3 hard tip 80.0 8 63 163 12 93 I-V-IO I-V-4 3 hard tip 81.0 8 63 163 12 90 I-V-9 I-IV-4 3 hard tip 83.0 8 64 162 12 90 I-VI-7 I-V-5 3 hard tip 83.0 8 63 162 12 94 I-V-9 I-IV-6 3 hard tip 84.0 8 62 163 12 92 I-V-8 I-V-3 3 hard tip 84.5 8 63 162 12 96 I-V-9 I-V-4 3 hard tip 85.0 8 63 164 12 91 I-V-8 I-IV-4 3 hard tip 85.0 8 65 163 12 96 I-V-7 I-V-3 3 hard tip 85.0 8 63 160 11 91 I-IV-IO 1-I11-6 3 hard tip 86.0 8 63 165 12 96 I-VI-8 I-V-4 3 hard tip 86.0 8 62 167 II 95 1-V-9 I-IV-4 3 hard tip 87.0 8 63 165 12 93 I-V-8 I-IV-6 3 hard tip 87.5 8 64 164 12 95 I-V-8 I-VIII-2 3 hard tip 88.0 8 65 164 12 96 I-V-6 I-V-5 3 hard tip 88.0 8 64 164 I] 96 I-VI-7 I-IV-3 3 hard tip S8.0 8 64 163 12 93 I-VI-6 I-VII-3 3 hard tip S9.0 8 64 159 II 90 1-V-4* 1-V-6 3 hard tip 90.0 8 62 165 12 94 I-V-6* I-V-4 3 hard tip 93.0 8 63 167 II 95 I-IV-8* I-VIl-4 3 hard tip 93.0 8 63 159 I I 90 I-V-7* I-V-5 3 hard tip 101.0 8 63 160 13 89 l-IV-7* I-VI-5 3 hard tip ..... ~-. -- - - - ._------~- 90.3 8 62 168 12 95 I-IV-5* l-VI-2 2 hard tip 89.0 8 63 164 12 96 I-V-6* I-V-4 2 hard tip 84.5 8 65 163 12 95 0-II-4 0-V-5 2 hard tip 75.0 9 63 160 14 91 0-V-12 0-IV-3 2 hard tip

• c .. broken fang; D = damaged. hispanus leptocephali, Schmidt (1913) 10- head, the last (No.9) just in front of the eludes the following: "Pigmen tatioll. The anus .... It has 3 postanal patches of pig- preanal pigment consists of 9 gut patches, ment besides one near the end of the tail. ... " the first of which (No.1) is found near the Thus, in number of ventral pigment aggrega- 460 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Figure 11. Ophichthus melanoporus: a-leptocephalus 83.4 mm TL; b-head of specimen 80.0 mm TL; c-head of specimen 78.5 mm TL. tions (nine, including a throat patch, a patch TL in larvae, 45% TL in elver, relative pre- on each of seven gut swellings and a patch at dorsal length decreases from 69% to 42% the anus) and subcutaneous spots below TL in larvae, then decreases further during the midline on the tail (four), our specimens transformation resulting in predorsal length agree with Schmidt's O. hispanus leptocephali of 17% TL in elver (Table 10). and add circumstantial support to Kanaza- Pigmentation.-Every myoseptum (except wa's observations. several of anterior few) with pigmented dashes just ventral to midline; gut pigmented Ophichthus ocellatus (Lesueur) ventrally with accumulation of spots under (Figs. 13, 14, 15 and 16; Tables 6, 7 and 10) first two swellings and sparsely under re- Diagnosis.-Ophichthus larva with 126 to mainder of gut; gut pigmented dorsally with 142 myomeres characterized by four to six accumulation of spots on each swelling; subcutaneous spots below midline on tail, specimens over 45.0 mm with additional two anal base pigmented with single spot at base spots between first two swellings; four to of every ray, gut with nine weak swellings six subcutaneous spots below midline on tail; and pigment along ventral gut surface. anal base pigment absent in specimens less than 30.0 mm TL, sparse in specimens 33.0 Description.-164 specimens examined (plus to 35.0 mm TL, and with single spot at base 97 additional specimens), 2 11.0 to 82.0 mm TL; myomeres 126-142; preanal myomeres 62-78; anterior margin of liver at myomere 8-12; posterior margin of liver at myomere 19-22; first major artery joins aorta at myo- - - mere 10-18; last two vertical blood vessels join aorta at myomere 57-63 and myomere A~~UST 63-69 respectively; dorsal fin origin at myo- (\ I*(24.Dm'Tl) - mere 46-59 in larvae, myomere 30-32 in gut, the last two vertical blood vessels relatively close together; maxillary dental for- N~iEMBER mula 0 to I + II to VII + 3 to 9; relative preanal length decreases from 81% to 57% !,I - 45,0- 500- 55.0- 60.0- 65.0· 70.0- 750 000- 85.0- 900- 49,9 54_9 599 649 69,9 74,9 799 849 899 949

2 Additional specimens of O. ocellalus and O. gomesi were SIZE GROuPS1mrrTU plotted on the distribution maps but were not examined for morphometric and pigment characters. Counts in the de- Figure 12. Length-frequencies of Ophichthus scriptions depict the ranges in all specimens while those in Tables 10 and 11 are for selected size groups. melanoporus leptocephali. FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 461

Figure 13. Ophichlhus ocellatus: a-leptocephalus 64.5 mm TL; b-head of specimen 38.5 mm TL,' c-head of specimen 63.9 mm TL. of every ray in specimens larger than 36.0 Bight are apparently distributed by the mm TL; pigment along dorsal edge of body southerly-flowing Carolinian Coastal Cur- present in some specimens; few gular spots rent, for most of the smallest larvae caught in present; few spots on snout and lower jaw December, April, and September were cap- (Fig. 13b, c). tured near Cape Hatteras (Fig. 15). Pre- sumably, as they grow, some of these larvae Discussion.-Leptocephalus caudomaculatus drift south and are caught in subsequent (Eigenmann and Kennedy, 1902, p. 87) is ~onths. Larvae are also occasionally ear- referable to Ophichthus ocellatus. The total ned north by the Gulf Stream as evidenced myomere count in L. caudomaculatus (127- by our captures as far north as Hudson 130) falls within the range of our specimens Canyon (Fig. 14). (126-142) as does the preanal count (70- . 70.0 mm) premetamorphic to 3 insignificant chromatophores below the leptocephali are present the year-round. median line ... ") is characteristic of Ophich- Our only elver capture was a 58-mm indi- ~hus and Eigenmann and Kennedy (1902) vidual caught in May near Cape Fear, N.C. Illustrate the gut in their species as having There are no traces of the larval pigment pat- nine weak swellings, each with a cluster of tern. Instead, the body and head are straw- pigment spots dorsally, which is characteristic colored with an overlying scattering of dark of O. ocellatus. Eigenmann and Kennedy spots. There are 137 vertebrae, of which 53 (1902) report a lack of pigment at the base are preanal. The preanal distance equals of the anal fin, but we feel the spots could be 45% of the total length. The predorsal overl?oked with poor lighting or optics, distance equals 17% of the total length. The especially since each spot is located at the dorsal fin origin is located behind the pec- junction of. the ray base and pterygiophore, an area WhIChcasts a "shadow" with indirect toral fin origin by a distance equal to 2% lighting. times the length of the pectoral fin. In this Ophichthus ocellatus leptocephali are com- character, the specimen approaches the con- mon constituents of the ichthyoplankton dition found in nominal O. retrapinnis south of Cape Hatteras (Fig. 14). Many of (Eigenmann, 1887). the leptocephali caught in the South Atlantic Ophichthus ocellatus larvae have a wide 462 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Table 9. Meristics and body proportions (expressed as percentage of total length) of larval and transforming (below dashed line) Ophichthus melanoporus

-- -. ~ Subcu- Myomeres Teeth tan eo us Size Predorsal Preanal Tail Caudal (mm TL) Length/TL Lcngth/TL Total Predorsal Preanal Maxilla Mandible Spots Tip ------24.0 D 83 D D 108 l-II1-4 1-11-2 0 D 46.3 18 73 175 17 104 I-IV-4 l-IV-2 4 4 rays 47.0 14 78 182 13 102 1-V-4 l-IV-6 4 5 rays 51.5 12 77 183 14 107 I-V-6 I-VII-2 4 5 rays 52.0 12 76 178 14 103 I-VI-5 I-VII-3 4 4 rays 54.8 13 75 180 14 105 I-V-5 I-VI-2 4 5 rays 56.0 12 69 183 14 105 I-V-7 I-VI-3 4 5 rays 57.5 12 66 185 13 110 1-VI-5 1-VII-3 4 rudimentary rays 64.0 12 66 182 14 105 I-V-6 I-V-3 4 rudimentary rays 66.0 II 66 185 13 110 I-V-5 I-V-2 4 rudimentary rays 70.0 12 68 184 14 103 T-V-6 I-VI-3 0 rudimentary rays 70.0 11 65 190 14 106 I-V-6 I-V-2 0 rudimentary rays 72.0 11 65 183 13 105 1-IV-9 I-V-4 I rudimentary rays 75.0 12 64 183 13 104 I-VI-7 I-V-3 0 rudimentary rays 75.5 ]2 65 ]83 ]4 105 I-V-6 I-VI-3 1 rudimentary rays 76.0 9 64 186 13 105 I-IV-5 I-V-5 0 hard tip 77.0 11 63 180 14 102 I-V-7 I-V-2 I hard tip 78.0 11 63 186 13 106 I-VI-7 l-VI-4 1 hard tip 78.0 11 63 184 13 ]06 I-V-6 I-IV-2 0 hard tip 78.0 11 64 181 13 105 I-VI-6 I-IV-3 0 hard tip 78.5 11 65 182 16 107 I-V-7 I-VII-3 0 hard tip 79.8 11 66 183 13 107 I-IV-7 I-VI-2 0 hard tip 80.0 10 63 181 ]4 101 1-V-4 1-VI-3 0 hard tip 80.0 11 64 179 13 106 1-V-7 I-IV-2 0 hard tip 81.0 ]0 64 180 13 102 I-V-6'" 1-VI-3 0 hard tip 81.0 11 64 185 13 102 I-VII-4 1-VII-4 0 hard tip 82.0 11 64 183 13 103 I-VI-8 I-V-2 0 hard tip 83.0 12 63 186 14 104 I-V-6'" I-V-3 0 hard tip 83.0 11 64 179 13 103 I-V-3 I-V-4 0 hard tip 84.0 12 66 181 ]4 103 I-VI-4 I-IV-4 0 hard tip 86.0 12 66 181 13 102 I-V-7 I-V-4 0 hard tip 87.0 11 65 188 13 108 1-VI-6 1-V-3 0 hard tip 88.0 11 64 185 13 110 I-VI-6 I-IV-3 0 hard tip 90.0 11 65 187 14 108 I-V-6 I-V-2 0 hard tip 92.0 10 64 184 13 108 I-VI-5'" I-IV-3 0 hard tip ------90.0 9 61 178 13 102 0-IV-5 1-V-5 0 hard tip 88.9 9 62 180 12 105 I-V-8* I-V-2 0 hard tip 88.9 9 63 181 16 106 I-V-lO'" I-VII-2 0 hard tip 84.0 9 63 182 14 103 1-V-8* 1-VI-3 0 hard tip 83.4 10 63 184 13 106 1-IV-6'" 1-V-3 0 hard tip 79.2 9 63 182 12 105 1-V-9'" 1-VII-2 0 hard tip 78.0 9 61 181 13 104 0-IV-4 1-IV-6 0 hard tip 74.0 10 63 186 13 107 I-VI-4'" I-VII-3 0 hard tip ------• = broken fang; D = damaged. spread (of 16) in myomere counts but the leptocephali with less than 133 myomeres are slight bimodality seen in the frequency-dis- seen in Figure 14 to extend across nearly tribution (Fig. 33) is not related to geog- the entire range of this species' occurrences, raphy as it is in other species (see Pisodono- a situation which is in marked contrast to phis Gruentifer discussion). On the contrary, the distribution of low-myomere representa- FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 463

Table 10. Meristics and body proportions (expressed as percentage of total length) of 62 larval, transforming (between dashed lines) and juvenile Ophich rhus oce/latus

Subeu- Myomeres Teeth· taneous Size Range Predorsal Preanal Tail Caudal (mmTL) Length/TL Lenglh/TL Total Predorsal Preanal Maxilla Mandible Spots Tip II

15.0-20.0 D 70-81 132-138 D 66-76 1-1l-3 l-IV-2 4 finfold 6 20.3-22.0 61 71-76 136-137 52 69-71 1-11-3 1-III-2 4-6 finfold 3 25.3-28.9 65-69 67-72 132-137 54-55 64-74 1-11-4 I-IV-2 5 finfold 3 31.7-34.2 47-53 64-71 133-139 48-56 66-75 1-II-4 1-IV-2 5-6 finfold 9 35.4-38.5 50-52 65-68 135-138 47-53 72-74 I-IV-5 I-V-2 5 finfold 4 40.2-44.0 48-53 62-69 129-142 49-54 67-73 I-IlI-5 I-V-2 4-5 finfold 9 48.8-49.0 51 64 130-139 55 72-74 I-IV-4 I-VI-3 4 5 rays 2 50.2-55.0 48-53 59-66 129-137 55-59 65-74 I-IV-6 I-V-5 4-5 5 rays 6 56.3-59.5 49-54 57-66 130-140 53-58 66-75 I-IV-6t I-Vl-3 4-5 hard tip 6 64.1-64.5 50 62-65 130-133 57-58 74-75 I-V-7t I-VII-3 4 hard tip 3 67.0-68.0 49 64-65 128-131 55-56 73-76 I-V-6t I-IV-7 4 hard tip 2 70.8-75.0 43-45 59-64 128-139 50-52 70-77 I-V-6t I-VIII-2 4 hard tip 4 77.5 42 59 136 50 72 I-V-7 I-VI-2 4 hard tip I ------.. .------.------. 74.0 28 56 134 32 69 I-IV-4t I-V-4 4 hard tip I 55.3 30 56 130 32 64 I-IV-4t I-V-2 4 hard tip 1 46.6 26 57 135 30 69 I-IV-4t I-IV-2 4 hard tip I -.------"-----.------_.--- 58.0 17 45 137 14 53 No Larval Teeth 0 hard tip (elver) (vert. ) • = modal counts; t = broken fang; D = damaged. tives of P. cruentifer. Nor is there a rela- these dorsally pigmented larvae is indicated tionship between the low-myomere speci- within the overall distribution and shows this mens and month or year of capture or size of character to be independent of extremes in the individuals (any of which might affect myomere development. Nor is dorsal pig- myomere development). We can only con- ment related to geographic range, since larvae clude that the myomere-number bimodality with this character were evenly distributed will be reflected in a similar bimodality in throughout the range of occurrences of the the total vertebrae of the adult population whole collection. Finally, the presence of but we can offer no explanation for its cause. dorsal pigment is not seasonal, for larvae It would be interesting to analyze vertebral with this character were captured in all numbers in those O. ocellatus adults which months when other O. ocellatus larvae were exhibit the posterior origin of the dorsal fin taken. If pigment is present along the dorsal typical of nominal O. guttifer and O. retro- margin, it is only in larvae larger than 40.0 pinnis. Schroeder (1941) referred O. gut- mm TL, but in these larger larvae the char- tifer to the synonymy of O. ocellatus after acter is not always apparent. We have no examining several external morphological reason to believe that the presence or absence features of both. In view of our observations of dorsal pigment is due to genetic differ- on myomere counts, it may be worthwhile to ences. It appears instead to be due solely to repeat his study and add to it an analysis of individual variations in pigmentation. vertebral counts. Pigment along the dorsal margin of the Ophichthus gomesi (Castlenau) body is present in some of our specimens, (Figs. 17, 18, 19 and 20; Tables 6, 7 and 11) although after 5 to 10 years' preservation, the spots are faint and barely visible. In Diagnosis.-Ophichthus larva with 139 to Figure 33, the total-myomere distribution of 150 myomeres characterized by four to five 464 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

'1./.•...... i&,\ ..i

I"\~ ,'..ii

~; ,}:r/ ,'l, .i

JJ"

J. \

0 0 , cP "

J{f"

,'t.. " " ,~

,.. ,,. -- --=-='----'----'-== Figure 14. Occurrences of Ophichthus ocellatus leptocephali. Specimens with less than 133 myomeres designated by., those with 133 or more myomeres designated by 0 (see Pisodollophis cruentiter discussion). Occurrence of elver designated by E. FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 465

Figure 15. South Atlantic Bight capture locations for six size groups of Opl1ich/ll/ls acel/a/us leptocephali.

slJbcutaneous spots below midline on tail, lary dental formula 0 to 1 + I to VIII + 1 anal base pigmented with single spot at base to 10; relative preanal length decreases from of each ray, gut with eight weak swellings, 79% to 54% TL in larvae, and from 53% and ventral gut pigment restricted to first to 51% TL in transforming specimens; rela- two swellings. Last vertical blood vessel joins tive predorsallength decreases from 63% to aorta about 10 myomeres anterior to vent. 50% TL in larvae, and from 49% to 40% TL in transforming specimens (Table 11). Description.-150 specimens examined (plus 419 additional specimens),2 14.5 to 98.4 mm Pigmentation.-Every myoseptum (except TL; myomeres 139-150; preanal myomeres several of anterior few) with pigmented 62-79; anterior margin of liver at myomere dashes ventral to midline; ventral gut pigment 10-14; posterior margin of liver at myomere restricted to first two swellings, dorsal gut pig- 21-27; first major artery joins aorta at myo- ment a cluster of spots over each swelling; mere 7-21; last two vertical blood vessels four to five subcutaneous spots below mid- join aorta at myomere 55-79 and myomere line on tail; anal base pigment absent in speci- 61-79 respectively; dorsal fin origin at myo- mens less than 57.0 mm, with single spot at mere 60 to 69 in larvae, 47 to 65 in trans- base of each ray in larger specimens; few forming specimens; gut with eight weak gular spots present; few spots on snout and at swellings; opisthonephros long, lying along tip of lower jaw (Fig. 17b, c). dorsal surface of gut; the last two vertical Discussion.-Leptocephalus morrisii Eigen- blood vessels relatively close together; maxit- mann and Kennedy (1902) (based on two 466 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3. ]978

also mention "a row of pigment cells along

CEMBt n12 the base of the anal" and "sides with a series L: • of linear spots on the myocomma beneath ~ median line." Finally, the preanal and total JANUARY------~I n.J6 myomere counts (69 and 142) and position . of the dorsal fin origin ("four segments in I FE"UARY 4 ",20 ------..----- front of the anus") in their specimen coin- , - cide with the counts in our series. MARCH The distribution (Fig. 18) and length- o~,I ".' ------_ frequencies (Fig. 19) for Ophichthus gomesi

RIL are similar to O. ocel/atus, indicating that the "·10 two species probably spawn in the same ~L ------areas and that the developing leptocephali

I ",29 MAY ILl = drift along similar routes. Most spawning ,,---I .--- - - apparently occurs in the spring and summer, JUNE and larger larvae are commonly taken in late ~,I ""- summer and fal!. All of the larvae under ~ 30.0 mm (Fig. 20) were captured on tran- 5 I JULY ~ ; ",5 -- - sects off Cape Hatteras or Ocracoke Inlet, - N.C. With increasing size, each 10-mm size AUGUST ".7 group was distributed farther south in the :1 - South Atlantic Bight, until finally the large, SEPTE,yafR premetamorphic larvae (>70.0 mm) be- "" ,I ---- came evenly scattered over the shelf. o:rOU::R Adult O. gomesi presumably spawn far ",28 :1 enough offshore for their eggs and prelarvae . to be carried north by the Gulf Stream. We NOVEM&R n.l0 ------I believe the larvae are "sheared off" by the ;100' 1:'0' roc- 2:'0- JOO- 3:iO' 400_ 4~O· 500- ~~O· 600· ~O- 100- 750- 600- Carolinian Coastal Current in the Cape Hat- 14g 199 2411 2911 349 J;9 ----449 499 54 {I 511It 649 ~1I11 --7~II 1\I1l 64 ') teras area, reverse their direction, and con- Figure 16. Length-frequencies of OphichthllS tinue their development as they drift south. ocella/lls leptocephali. Depending on spawning location, larvae vary in size when they reach the Cape Hatteras area; those spawned farthest south will be specimens, 74 and 86 mm), renamed L. further along in their development and thus eigenmanni by Lea (1913) is in part refer- bigger than those spawned in the northern able to Ophichthus gomesi.H Eldred (1966) part of the bight. referred the 74-mm specimen to Myrophis Our captures of leptocephali south of punctatus, but the 86-mm specimen closely Long Island and Martha's Vineyard indicate fits our O. gomesi description. Eigenmann that occasional larvae do not enter the rotary and Kennedy do not mention weak gut drift pattern south of Cape Hatteras but con- swellings (which would not be apparent in tinue their development as they drift with the a specimen as close to metamorphosis as Gulf Stream and ultimately may metamor- theirs is) but do refer to eight pigmented phose in inshore waters as far north as spots along the top of the alimentary canal Massachusetts. This might explain the un- and a pigment spot below the alimentary usual occurrence of adults in Massachusetts canal opposite the second spot above. They waters which, as Backus (1957) points out,

3 The Eigenmann and Kennedy specimens should not be is not necessarily attributable to the adults confused with LePtocephalus morris;; Gmelin (1788) which Castle (1969) has referred to Conger cOllger. drifting north with the Gulf Stream. FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 467

Figure 17. Oplziclztlzus gomesi: a-leptocephalus 81.5 mm TL; b-head of specimen 54.0 mm TL; c- head of specimen 85.5 mm TL.

Genus Pisodonophis liver at myomere 20-27; first major artery Pisodonophis cruentifer (Goode and Bean) joins aorta at myomere 8-18; last two verti- (Figs. 21, 22, 23 and 24; Table 12) cal blood vessels join aorta at myomere 55- 65 and myomere 62-70 respectively; dorsal Diagnosis.-Ophichthid leptocephalus with fin origin at myomere 44-57; gut strongly 142 to 162 myomeres characterized by flank looped, with nine peaks; opisthonephros pigment, spots along dorsal edge of body, and long, lying along dorsal surface of gut, ending looped gut with spots on dorsal and ventral over next to last gut peak; maxillary dental surfaces, on and between swellings. formula 1 + II to VII + 2 to 9; relative pre- Description.-59 specimens examined, 13.0 anal length decreases with growth from 75% to 83.5 mm TL; myomeres 142-162; pre- to 53% TL; relative predorsal length de- anal myomeres 66-75; anterior margin of creases with growth from 48% to 39% TL liver at myomere 8-12; posterior margin of (Table 12).

Table 11. Meristics and body proportions (expressed as percentage of total length) of 74 larval and transforming (below dashed line) Oplzichthus gomesi

Subcu- Myomeres Teeth' taneous Size Range Predorsal Preanal Tail Caudal (mmTL) Length/TL Length/TL Total Pre dorsal Preanal Maxilla Mandible Spots Tip n ------14.5-18.0 ND 73-79 140-141 ND 65-70 1-11-4 1-11I-3 5 finfold 2 21.0-28.2 ND 69-72 143-149 ND 69-72 1-11-4 1-11-4 4 finfold 5 30.5-38.9 60-63 66-72 145-148 60-63 68-71 1-11-5 l-IV-2 4 finfold 6 41.5-49.1 62-64 61-68 141-150 62-66 68-74 1-V-5 I-V-2 4 finfold 9 50.2-56.8 60-63 57-63 143-147 65-66 70-73 I-V-4 I-V-3 4 5 rays 5 60.5-69.0 56-57 56-61 141-148 64-69 68-73 I-V-6 I-VI-2 4 5 rays II 70.7-79.8 52-56 53-59 142-147 62-67 67-73 I-VI-6 I-VII-2 4 5 rays or 14 hard tip 80.1-88.8 53-55 55-58 141-147 60-68 68-74 I-V-6t I-VI-3 4 hard tip 14 95.0 50 54 143 65 72 I-V-6t l-VI-4t 4 hard tip 1 ------94.3 49 53 141 63 70 0-III-6 I-V-3t 4 hard tip 1 78.0-74.0 41-45 49-55 139-144 51-65 62-72 0-V-7 l-IV-3 4 hard tip 5 63.5 40 51 141 47 72 0-IV-6 I-VII-4t 4 hard tip 1 • = modal counts; t = broken fang; ND = not discernible. 468 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Pigmentation.-Myosepta sporadically pigmented with few dashes ventral to midline; flank pigment present on upper angle of a few myosepta between midline and dorsal edge of body and on lower angle of a few postanal myosepta between midline and ventral edge of body; extent of flank pigment in- creases in specimens from about 50.0 mm ". o TL to about 79.0 mm TL when the flank ,,' pigment becomes faint; prominent pigment spots along dorsaL edge of body; gut pigmented on and between swellings, on dorsal , as well as ventral surfaces; anal base pigment ,.' ,,' 70' in short, linear clusters separated by unpigmented gaps; five to seven subcutaneous spots below midline on tail; spots on nape, snout,

33' lower jaw, and gular area all increase in ro' extent and intensity with growth (Fig. 21b). Literature.-Richardson (1974) described the eggs and early larvae (5.8-34.2 mm) of P. cruentifer. Differences in pigment pat- o &.t.'" terns between her larvae and ours are due to

J3' growth. Larger larvae add flank pigment, subcutaneous spots on the tail, and dorsal gut pigment between the swellings. '"'" Discussion.-McCosker (1977) refers the western Atlantic Pisodonophis cruentiter to ~\ Ophichthus while retaining Pisodonophis as 30' a valid genus. Our own examination of P. cruentifer adult specimens indeed indicates a cn-o close affinity to Ophichthus (shared external 1I3uL(dlflde5 characters include a narrow-based pectoral '6',,. fin, low anal and dorsal fins, and dorsal ". origin posterior to the gill slit) although P. cruentifer would seem to be considerably "'" more slender than Ophichthus spp. ,,. Larval P. cruentifer, however, are significantly different from larval Ophichthus and ,~ this fact seems to us to preclude the alignment of P. cruentifer with Ophichthus. Dif- ferences include: (1) P. cruentifer larvae are sporadically pigmented on the myosepta along the midline while Ophichthus larvae ,.' have spots on every myoseptum; (2) P. cruentifer larvae have pigment on the flank, Ophichthus larvae do not; (3) P. cruentifer Figure 18. Occurrences of Opl/iehthlls gomesi leptocephali. Each symbol represents the capture larvae have pigment along the dorsal edge of location of one leptocephalus. the body, Ophichthus larvae do not (except FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 469

JANUARY ~I n,2

APRil n,] b' MAY n,2 61

JUNE n,14 :1 • JULY :I n,32 11IIIII.

SEPTEMBER n,]6

1:31 OCTOBER . 0,55

NOVEMBER n,2 6I

J DEn:iMBER

10.0" 150- 20,0- 25,0- 30,0- 35.0- 40.0- 45,0- 50,0- 55.0- 50,0- 65,0- 70.0- 75.0- 80.0- 85.0- 900- 950- 14.9 19.9 24,9 299 34,9 39.9 44.9 49.9 54.9 59.9 64.9 69,9 74,9 79,9 84.9 89.9 94,9 99.9 SIZE GROUPS (mmTU

Figure 19. Length-frequencies of Ophichthus games; leptocephali. in rare examples of O. ocellatus); (4) gut cruentifer, although we acknowledge the loops are pronounced in P. cruentifer larvae, pending change in the generic name. barely noticeable in Ophichthus larvae. These most-heavily pigmented of all Because of these differences, therefore, we ophichthid leptocephali were captured in the hesitate to refer these larvae to Ophichthus Middle Atlantic Bight (Fig. 22) where the and are here describing them as Pisodonophis adults are commonly taken in deepwater 470 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Figure 20. South Atlantic Bight capture locations for six size groups of Ophichfhus gamesi leptocephali.

trawl tows. Our catches are noteworthy for and Kennedy, 1902) is referred to the syn- the wide spread in myomere counts. Whereas onymy of Pisodonophis cruentifer (Richard- the myomere counts in other species approxi- son, 1974). In addition, Leptocephalus mate a range of 10-12, the myomere range Leiuranus sp. (Castle, 1965; Della Croce and in P. cruentifer larvae is 20. We have chosen Castle, 1966) from Australasian waters seem to illustrate the distribution of total myomeres referable to the same genus as our specimens in two ways. Figure 23 shows the bimodality and the myomere range indicates the involve- in the frequency of total counts and suggests ment of three species. If the early larvae re- that the differences in meristic development ferred to Pisoodonophis boro (sic) by De1s- are due to geographic variation. In Figure man (1933) and the larger larvae referred to 22, those larvae with less than 148 myomeres P. hijala by Jones and Pantulu (1955) arc are designated by a solid circle to emphasize correctly identified generically, then there is their occurrence in the southern part of the further reason to suspect that P. cruentifer Middle Atlantic Bight. An analysis of vari- belongs in some genus other than Pisodono- ance performed on the myomere counts of phis, for the former larvae lack pigment on the larvae from the north and those from the the dorsal edge of the body and along the south indicated a significant difference (P < flank on the upper and lower angles of the 0.001). The northern larvae had a mean myosepta. We feel that both of these features count of 154 myomeres while the southern (which are present in P. cruentifer larvae) larvae had a mean count of 148. are significant generic characters. Leptocephalus mucronatus (Eigenmann The influx of small larvae in August in our FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 471

b Figure 21. Pisodonophis cruentifer: a-leptocephalus 59.0 mm TL; b--head of specimen 52.0 mm TL; c-midsection of body of specimen 52.0 mm TL.

collections (Fig. 24) indicates summer Callechelys leptocephali are characterized spawning in this species, which agrees with by long, undulating guts, swollen in eight observations made by Richardson (1974) places. The liver occupies the first two swell- based on egg collections. ings of the gut. There are aggregations of pigment on top of each gut undulation and Genus Callechelys the myosepta are sporadically pigmented along the midline. Subcutaneous spots are Storey's ( 1939) revision of the genus present below the midline on the tail. Callechelys included the western Atlantic species C. muraena, and the new species C. Callechelys sp. perryae. Kanazawa (1952) described C. (Figs. 25 and 26) bilinearis and Rosenblatt and McCosker ( 1970) referred Gordiichthys springeri and Diagnosis.-Callechelys larva with 182 to Cryptopterygium holochroma to Callechelys. 183 myomeres characterized by sparsely pig- Vertebral counts for these five western At- mented myosepta, four subcutaneous spots lantic species are contained in Table 1. below midline on tail, and gut with eight un- We arrived at the generic identification of dulations. these larvae after grouping them (with the Description.- Two specimens examined, closely related Letharchus velifer larvae) on 32.0 to 86.0 mm TL; myomeres 182-183; the basis of similarities in head, gut, and liver preanal myomeres 100-101; anterior margin structure and then matching the myomere of liver at myomere 11-12; posterior margin ranges with vertebral ranges in adults. This of liver at myomere 25-27; first major artery method allowed us tentatively to assign the joins aorta at myomere 21; last two vertical generic name Callechelys to the group. We blood vessels join aorta at myomere 99 and verified this tentative arrangement by com- myomere 101-102 respectively; dorsal fin paring our specimens with Callechelys cliffi (Bohlke and Briggs, 1954), the description origin at myomere 17; long gut with eight of which was based on a recently transformed undulations; opisthonephros slim, lying juvenile which retained larval pigmentation. along dorsal surface of gut, the last two verti- The pigment patterns and preanal lengths in cal blood vessels relatively close together; our larvae and the C. cUfti holotype are iden- maxillary dental formula 1 + II to V + 6 to tical and provide the supporting evidence 8; relative preanal length 77% TL at 32.0 necessary to our alignment. mm, 62% TL at 86.0 mm; relative predorsal 472 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Table 12. Meristics and body proportions (expressed as percentage of total length) of 29 larval Pisodo- nophis cruentiter

Subcu- Myomeres Teeth taneous Size Predorsal Preanal Tail Caudal (mm TL) Length/TL Length/TL Total Predorsal Preanal Maxilla Mandible Spots Tip 16.2 ND 75 152 ND 70 1-11-2 l-IT-4 5 finfold 18.0 ND 75 150 ND 69 1-11-2 1-I1I-I 5 finfold 20.5 ND 70 153 ND 70 1-11-3 1-11-4 7 finfold 21.5 48 63 155 47 72 1-11-3 1-I1I-6 6 finfold 26.3 47 63 149 44 68 l-IV-4 I-IV-4 7 finfold 28.8 D 62 152 D 73 1-111-3 I-I1I-4 7 finfold 29.6 51 63 152 49 71 1-11-4 l-1ll-3 6 finfold 31.5 49 62 152 52 73 1-11-4 1-IV-2 6 finfold 32.8 48 63 153 51 72 1-11-4 1-11-4 6 finfold 33.4 49 64 148 44 66 1-11-4 1-1II-4 4 finfold 35.8 49 60 150 47 71 1-V-2 I-IV-6 6 finfold 37.5 46 62 158 49 71 1-11-5 1-IV-4 6 finfold 39.7 49 61 145 49 68 1-IV-5 1-VI-3 6 fin fold 40.5 48 61 155 50 72 1-111-4 I-IV-3 6 finfold 41.3 51 63 145 54 70 1-11-5 1-V-3 6 finfold 44.0 50 60 147 52 70 I-1ll-3 I-V-4 6 finfold 49.0 51 58 151 53 72 1-1V-4 l-VI-3 6 finfold 51.3 44 55 147 50 69 1-V-5 I-VI-2 6 5 rays 53.4 49 60 157 53 77 1-11-7 I-V-2 6 6 rays 55.3 46 57 147 55 70 I-IV-5 1-VII-2 6 6 rays 57.0 40 55 152 50 74 1-1V-5 1-1II-6 6 6 rays 59.0 41 54 158 52 73 1-11-9 1-IV-3 5 6 rays 61.0 42 56 146 54 74 I-V-5 1-11-6 5 hard tip 63.5 37 53 148 48 71 1-V-6* 1-V-2 6 hard tip 68.5 41 53 151 49 72 1-IV-6 I-VI-3 5 hard tip 71.4 41 54 150 50 71 I-VI-5':' I-VII-3 5 hard tip 75.5 40 52 149 50 72 I-VI-6" I-VII-3 5 hard tip 79.0 38 53 147 47 69 1-V-9* l-I1I-7 5 hard tip 83.5 39 53 147 52 67 I-V-6* 1-VI-4 5 hard tip ND = not discernible; D = damaged; * = broken fang.

length 12% TL at 86.0 mm (not discernible while in our 86.0 mm larva the tail com- at 32.0 mm). prises 37.0% of the total length. (Since Callechelys lacks a caudal fin, total and Pigmentation.-Myosepta sparsely pigmented standard lengths are understood to represent ventral to midline; gut pigmented dorsally the same measurement.) The assignation of with prominent spot on each undulation and these larvae to C. perryae would thus require ventrally with spots on first two bulges; anal a posterior migration of the vent, a phenome- base sparsely pigmented with a few, round non unprecedented in anguilIiform metamor- aggregations of spots, four subcutaneous phosis. Although relative tail length might spots below midline on tail; few spots In be expected to change during larval develop- gular region and on snout (Fig. 25b). ment and transformation, larger, early meta- Discussion.-These larvae have myomere morphic larvae probably approximate the counts which approximate the vertebral range proportions manifested in adults. For ex- of Callechelys perryae. But the tails in adults ample, the tail length in the C. eliffi holotype compnse 31.0 to 32.8% of the standard (a recently transformed juvenile) is 43% length (McCosker and Rosenblatt, 1972) of the total length (Bohlke and Briggs, 1954) FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 473

while the mean tail length in eight adult specimens is 43.4% of the standard length (McCosker and Rosenblatt, 1972). Al- " though we were unable to find similar supporting figures for other ophichthid species, this evidence within the genus Callechelys 70 indicates that the proportions in our larger leptocephalus approximate those in adults. Capture locations are combined with Letharclzus velifer in Figure 26.

Genus Letharchus Letharchus velifer Goode and Bean " (Figs. 26, 27 and 28; Table 13)

Diagnosis.-Callechelys-type larva with 137 to 150 myomeres characterized by sparsely pigmented myosepta, three or four subcutaneous spots below midline on tail, and gut with 10 undulations.

Description.-57 specimens examined, 18.0 to 70.9 mm TL; myomeres 137-150; preanal myomeres 88-95; anterior margin of liver at myomere 10-14; posterior margin of liver at myomere 21-26; first major artery joins aorta at myomere 22; last two vertical blood vessels join aorta at myomere 84-89 and myomere 87-93 respectively; dorsal fin origin at myomere 8-11, slightly anterior to level of first gut loop; long gut with 10 undulations; opisthonephros slim, lying along dorsal surface of gut; the last two vertical blood vessels relatively close together; maxillary dental formula 0 to 1 + II to VI + 2 to 8; relative preanal length ranges from 76% TL at 36.1 mm to 68% TL at 60.5 mm; relative predorsal length decreases slightly 3S from 12'10TL at 40.7 mm to 9% TL at 60.5 mm (Table 13).

Pigmentatiol1.-In larvae smaller than about 45.0 mm, a streak of pigment on every fourth 75 or fifth myoseptum; in larger larvae, more myosepta posterior to vent are streaked than anterior; gut pigmented with large spot on dorsal surface of each undulation and smaller cluster between undulations; a more promi- Figure 22. Occurrences of Pisodollopllis cruentifer leptocephali. Specimens with less than 148 myo- nent intermediate spot between first and sec- meres designated by ., those with 148 or more ond undulations; anal base sparsely pig- myomeres designated by Q. 474 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

TQT';l MVOMH!ES ~6 1~8 00 ~ ~4, ~ ~s ~ ~ ---

N"34 NOll.TH Of DElAW •••.RE J.a.." -- ~'r.a..~o •• ----- .. ~I SEPTEM8ER",6 _ r 1.1 I- -- 1i ',ll 1~\1 'i'Jo. 1~" .'..',' ;:~, 4.,1G 4';\ \', '~1 I'· " •. , l .11' 1 1 ~4Q !~Q 74~ ~·l~ ~d'l .'19 44" 41lq <'4'1 'd~ 14" ~ 2 ) .1

SOUTH OF DELAWAR£ BAY N,,24 Figure 24. Length-frequencies of Pisodonophis "2 144 !46 I;a 150 152 154 crt/en/iter leptocephali. lorA.l Myo.WRES

Figure 23. Distribution of total myomeres in Piso- donophis cruen/iter leptocephali from two geo- east coast. The size distribution also indi- graphic areas. The mean myomere count for each group is indicated by x. cates this, for larvae of any size group are about equally distributed in the South At- lantic Bight and there are no north-south mented with linear clusters of spots; in trends in distribution by size. smallest larvae (18.0 to 20.0 mm), three Letharchus is closely related to Callechelys spots along dorsal edge of body, at about (Ginsburg, 1951; Bohlke, 1966; McCosker, level of myomeres 7, 15, and 30; dorsal pig- 1974), thus we might expect the larvae of ment lacking in larvae larger than 34.0 mm; the two genera to be similar, especially in three to four subcutaneous spots below mid- regard to the length of the gut, for both line on tail in larvae over 34.0 mm; a fifth genera have long guts and short tails. subcutaneous spot at tip of notochord in Letharchus velifer (the only western Atlantic larvae between 18.0 and 20.0 mm; few spots species in the genus) is distributed from in gular area, on snout and lower jaw (Fig. North Carolina to the Gulf of Mexico (Briggs, 1958) and has a vertebral count of 27b). 136 to 143 which coincides perfectly with our Discussion.-We originally identified these larvae. The distinguishing character in adult larvae as Callechelys muraena because of Callechelys and Letharchus (presence or ab- their resemblance to our Callechelys lepto- sence of anal fin) is not useful in larval cephali and to the C. cUffi holotype and be- studies, for finless adults do have fins in cause the myomere range coincided with the early larval stages. vertebral range in C. muraena. However, C. The length-frequencies we observed (Fig. muraena is distributed in the Gulf of Mexico 28) indicate that spawning occurs in spring along the west coast of Florida from Pensa- and summer and fully developed larvae are cola to Marco (Briggs, 1958) and there are present in South Atlantic Bight waters from no records of adults on the east coast of the ruly through October. United States. Although we have seen in the case of Ophichthus ophis that lepto- Genus Apterichtus cephali are often encountered in areas (i.e., (Leptocephalus caribbaeus Fowler complex) north of Cape Kennedy) where adults are not recorded, and it is certainly possible for The original description of Leptocephalus larvae spawned in the Gulf of Mexico to caribbaeus appears to have been based on a drift with the Florida Current into east coast deep-bodied, early metamorphic specimen continental shelf waters, we feel that the with "fins poorly developed and pectoral not widespread distribution of these larvae (Fig. distinct" and "tail nearly 2 in rest of body" 26) probably is the result of spawning of a (Fowler, 1944). We feel that Fowler's note species which is a common inhabitant of the concerning the fins indicates a degeneration FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 475

----- ~~~!F~ __-~_ a

Figure 25. Cal/echelys sp.: a-leptocephalus 86.0 mOl TL; b-head of same specimen; c-midsection of body of same specimen. of the larval finfold and that on completion looped gut with seven prominent peaks, bold of metamorphosis the pectoral fins will be pigment spots on each gut peak, and three lost and the dorsal and anal fins will be bold, subcutaneous spots below the midline poorly developed or absent. Six western on the tail. Head pigment includes a char- Atlantic ophichthid genera lack pectoral fins: acteristic accumulation of spots behind the Ichthyapus, Apterichtus, Letharchus, Cara- eye. Both lack pigment along the anal base lophia, Callechelys, and Aprognathodon. and lack preanal myosepta pigment. Our Both dorsal and anal fins are present in the specimens are apparently not as well-devel- latter three genera; Letharchus lacks an anal oped as Fowler's L. caribbaeus, for all retain fin but retains a dorsal; Ichthyapus and Ap- a vestige of a pectoral fin and discernible terichtus lack all vertical fins. vertical fin rays. Fowler's (1944) specimen has 129 myo- One of the types has a myomere count of meres. There are no vertebral ranges lower 127 (one specimen), which is in line with than 136-143 in species of Letharchus, Cara- the L. caribbaeus count. The second type lophia, Callechelys, or Aprognathodon (Ta- has a myomere range of 138 to 149 (20 ble I), while Apterichtus ansp and Ichthya- specimens), which compares well with the pus ophioneus have ranges of 123-132 and vertebral count in Apterichtus kendalli (Ta- 125-137, respectively. ble 1). We feel the foregoing provides prima facie Leptocephalus decimpunctum (Fowler, evidence that L. caribbaeus represents a larva 1938) from the Pacific is referable to Ap- of Apterichtus or Ichthyapus. The genera terichtus, Ichthyapus or a closely-related are separable as adults by differences in genus. Fowler mentions "fins poorly de- position of the posterior nostril and slight veloped, and apparently no pectoral" (al- differences in the nature of the gill slit though he illustrates the specimen with a (Bohlke and Chaplin, 1968)-differences pectoral fin bud) and the bold pigmentation which are not evident in leptocephali. Be- is unmistakenly similar to the L. caribbaeus cause of its marked resemblance to Apterich- pattern. Ius kendalli leptocephali, we are referring L. Capture locations for both types are com- caribbaeus to the synonymy of A. ansp. bined in Figure 29. The following distinct larval types are Apterichtus ansp Bohlke identical to L. caribbaeus and differ from (Figs. 29 and 30) each other in total myomere counts. Both types are deep-bodied and have a long Diagnosis.-Leptocephalus caribbaeus type (about two-thirds of total length), strongly- larva characterized by 127 myomeres. 476 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Description.-One specimen examined, 59.0 mm TL; myomeres 127; preanal myomeres 86; anterior margin of liver at myomere 9; posterior margin of liver at myomere 26; first major artery joins aorta at myomere 15; last two vertical blood vessels join aorta at myomere 76 and myomere 80 respectively; dor- ,,' sal fin origin at myomere 10; gut strongly o looped, with seven prominent peaks, its ,.' length 65% TL; maxillary dental formula 2 + IV + 7. Pigmentation.-Myosepta pigment restricted to dashes on a very few segments posterior ,,. to vent; pigment along anal base entirely absent; gut pigmented with circular aggregation of spots overlying each peak; three bold, round, subcutaneous spots below midline on tail; cluster of spots behind eye; few spots in .\ gular area and on snout (Fig. 30b). ". Discussion.-It is difficult to explain the ex- treme rarity of this leptocephalus in our col- ".7r lections. One or all of several factors could contribute to the lack of collections: the • I • relative scarcity of adults; the possibility ~\ that spawning (at least in the years when 30' we sampled) occurs in waters so far offshore .\ that the eggs and larvae drift with the offshore (eastern) edge of the Gulf Stream and ". •• f1 are thus beyond the scope of our operations; ,~1B' or, finally, that the leptocephali exhibit a depth preference which places them deeper than our various plankton nets sampled. We consider the second of the above factors to be ". the most likely, especially since our sole specimen was taken farther offshore than any other species.

".79' Apterichtus kendalli (Gilbert) (Figs. 29, 31, and 32; Table 14) ,.. Diagnosis.-Leptocephalus caribbaeus type larva characterized by 138 to 149 myomercs. Description.-20 specimens examined, 18.0 Figure 26. Occurrences of Letharchus veliter and to 68.3 mm TL; myomeres 138-149; pre- Cal/echelys sp. leptocephali. Each • represents the capture location of one L. vel iter leptocepha- anal myomeres 81-88; anterior margin of lus; each 0 represents the capture location of one liver at myomere 9-11; posterior margin of Cal/echelys sp. leptocephalus. liver at myomere 22-26; first major artery joins aorta at myomere 16-21; last two verti- FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 477

Figure 27. Letlwrchlls velifer: a-leptocephalus 65.0 mm TL; b-head of same specimen.

cal blood vessels join aorta at myomere 80- to 7; gut strongly looped, with seven promi- 84 and myomere 85-87 respectively; dorsal nent peaks, its relative length decreasing fin origin at about level of first gut swelling; from 85% TL at 18.0 mm to 65% TL at 68.3 maxillary dental formula 1 + II to VI + 2 mm; relative predorsallength decreases from

Table 13. Meristics and body proportions (expressed as percentage of total length) of 23 larva] and transforming (below dashed line) Letharc/1us ve/ifer

------Subcu- Myomeres Teeth taneous Size Predorsal Preanal Tail Caudal (mmTL) Length/TL Length/TL Total Predorsal Preanal Maxilla Mandible Spots Tip

18.0 ND 69 148 ND 92 1-111-2 1-IV-2 5 finfold 20.0 ND 68 146 ND 93 1-11-3 1-11I-3 5 finfold 34.5 ND 74 143 ND 90 1-11I-6 I-V-3 4 finfold 36.1 ND 76 145 ND 91 I-V-7 I-V-3 4 finfold 38.0 ND 76 141 ND 91 I-VI-5 l-IV-4 4 finfold 39.0 ND 75 139 ND 93 I-V-5 I-IV-3 4 finfold 40.7 12 76 148 10 95 1-11I-8 I-V-3 3 finfo]d 41.0 12 72 150 II 93 I-IV-6 I-VI-4 3 finfo]d 44.1 12 72 140 ]0 9] I-V-7 I-VI-2 4 finfold 44.5 12 72 ]46 II 92 I-V-3 I-V-O 4 finfold 49.5 II 69 143 10 9] ]-Y-5 I-VI-2 4 D 50.7 10 72 141 8 9] I-V-6 ]-VI-2 4 finfold 52.5 9 72 146 8 94 I-V-7 I-VI-2 4 finfold 53.6 ]0 72 145 9 95 I-IV-6 1-11-6 4 finfold 60.0 D 67 137 D 88 I-V-5* I-VI-2 3 6 rays 60.8 9 68 141 9 91 I-V-4 ]-VI-3 3 5 rays 63.2 10 68 145 9 91 I-V-7 ]-VII-2 4 5 rays 65.0 .10 70 143 10 93 I-V-7* I-VII-3 3 5 rays 67.0 9 67 142 10 90 I-VI-7* I-VII-2 4 hard tip 67.7 10 70 143 ]0 91 I-V-7* ]-VI-2 4 hard tip 70.9 8 68 142 8 92 0-V-6 I-VII-4 4 hard tip .. _------67.3 8 64 ]43 8 92 0-IV-7 I-V-3 3 hard tip 60.5 9 68 143 10 88 0-V-6 l-IV-2 3 hard tip ----~-- NO == not discernible; • == broken fang; D == damaged. 478 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

MAY n,3 ~I - - - ~I ------

61 N~EMBER

150- '200' 250- 300- 350- 400- ~ 500· 550' 600- 050· 700' 199 249 299 34 9 399 449 499 549 599 549 09!l 749 SIZE GROuPS (rr"TLl

Figure 28. Length-frequencies of Letllarehus velifer leptocephali. ". " "n,A ,., 19% TL at 29.8 mm to 12% TL at 68.3 mm " (Table 14). ,,' Pigmentation.-Myosepta pigment restricted '" to dashes on a very few segments posterior to vent; pigment along anal base entirely absent; ~\ gut pigmented with circular aggregation of JO' spots overlying each peak; three bold, round, subcutaneous spots below midline on tail; rTn cluster of spots behind eye; few spots on snout (Fig. 31b, c). ,..,.. Discussion.-Apterichtus kendalli apparently spawns from spring through summer and fully developed leptocephali are present in South Atlantic Bight waters from August ,.. through October (Fig. 32). The species has been recorded from Venezuela, the Ba- hamas, and southern Florida (Bohlke, 1968) and rarely from as far north as South Caro- lina (Dawson, 1959). The capture of 10 specimens in a single half-hour neuston net haul off the coast of ,,' South Carolina (Fig. 29) is the more noteworthy because the ophichthid larval catch Figure 29. Occurrences of two species of Apter- also included three Ahlia egmontis, one jelltus. Each symbol represents the capture location Ophichthus gomesi, four O. ophis, one O. of one leptocephalus; A = A. WISp; K = A. melanoporus, and one Apterichtus ansp. kendalli. This circumstance may have been the result FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 479

_/,_:-~.:=::--- , .

Figure 30. Aptericlltlls ansp: a-leptocephalus 59.0 mm TL; b-head of same specimen.

of a common spawning time and area for the gut. The most useful characters for these species and the consequent drifting to- identifying the seven genera discussed in this gether of the larvae. paper follow: Only Ahlia larvae have a short-based opis- SUMMARY AND DISCUSSION thonephros with two peaks on the dorsal Because we have not seen or described aspect and pigment streaks on almost every leptocephali of all western Atlantic ophich- myoseptum below the midline. thid genera, we are unable to construct an Only Myrophis larvae have a short-based identification key. Of those types described opisthonephros with two peaks on the dorsal herein, however, it is possible to arrive at a aspect and sporadic pigment along the myo- generic identification fairly quickly, without septa below the midline. resorting to myomere counts. Key features are the nature of the opisthonephros, nature Only Ophichthus larvae are pigmented with and extent of midline pigment, and relative streaks on every myoseptum (except for length and degree of swelling or looping of anterior few).

Figure 31. Apterichtus kendalli: a-leptocephalus 68.3 mm TL; b-head of specimen 67.3 mm TL; c- head of specimen 40.8 mm TL. 480 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

bers occur frequently among genera. After a b~"~IE ------generic identification has been made, how- JULY ever, myomere counts usually must be done bI ",I - in order to specifically identify or confirm the identification of a specimen. Total myomere AUGUST",12 __ distributions for the species described in this paper are combined in Figure 33. SEPTEMBER - Specimens which cannot be identified by n:l --- - the above criteria must be considered to represent genera not described in this paper. d O~,~OBE:""" - - Closely related ophichthid genera, however, 15.0- 200· 25.0- 30,0- 350- 40,0- ;150- 5')0- 550- 60.0- 650· probably have similar larvae, as is the case 19.9 24.9 299 301,9 39,9 449 499 54.9 59,9 64.9 -699 SIZE GROuPS (rr.'Tll Ll in other closely related teleost pairs. Exam- ples include: Gadus-Pollachius (Gadidae); Figure 32. Length-frequencies of Apterichtus kendalli leptocephali. Leiostomus-Micropogon (Sciaenidae); Etro- pus-Citharichthys (Bothidae); Sebastes-Heli- Only Pisodonophis larvae have flank pigment colenus (Scorpaenidae); Loweina-Tarleton- between midline and dorsal edge of body and beania (Myctophidae). We would expect postanally between midline and ventral edge Bascanichthys leptocephali to have longer of body. guts than Myrichthys leptocephali but to be otherwise similar. Other pairs (or triplets) of Only Callechelys and Letharchus larvae have ophichthids whose larvae one might expect long, undulating guts (62% to 77% of TL in to be similar include: Ophichthus-Quassi- our specimens) with gut pigment more con- remus, Callechelys-Letharchus-Aprognatho- centrated on the swellings than between. don, and Apterichtus-Ichthyapus. Bohlke's Only Apterichtus larvae have festooned guts (1966) description of three juvenile Apro- and lack pigment on preanal myomeres and gnathodon platyventris suggests that the along anal base. leptocephali of this species have eight sub- Preanal and total myomere counts have cutaneous spots below the midline on the tail, little (if any) utility in identifying larval and nine gut swellings, each with a major pig- ophichthids above the specific level since ment spot. Preanal midline pigment consists overlap and coincidence of myomere num- of eight major spots alternating with seven

Table 14. Meristics and body proportions (expressed as percentage of total length) of 10 larval A pter- iclaus kendalli

Subcu- Myomeres Teeth taneous Size Predorsal Preanal Tail Caudal (mm TL) Length/TL Length/TL Total Predorsal Preanal Maxilla Mandible Spots Tip

18.0 ND 85 144 ND 82 l-III-2 l-I1-3 3 finfold 29.8 19 69 140 13 85 l-II-4 I-IV-2 3 finfold 31.7 18 70 149 13 87 I-V-4 I-IV-3 3 finfold 37.5 17 68 145 16 87 l-IV-7 l-IV-2 3 finfold 40.8 17 68 145 15 84 I-V-4 1-V-3 3 finfold 46.0 16 66 147 15 88 I-V-3 1-VI-3 3 5 rays 55.0 14 66 138 13 85 I-V-5 I-VI-2 3 5 rays 55.5 15 66 145 17 87 I-V-4* I-VI-3 3 hard tip 67.3 12 62 142 12 82 I-VI-5* 1-VI-3 3 hard tip 68.3 12 65 145 8 85 I-V-5* I-VI-4 3 hard tip ND = not discernible; • = broken fang. FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 481

Alil!u ('fl"1

~ ~I \56 160 162 164 166 168 \70 152 154 156 ISS 160 162 164 165 /. /. /. /. TOTAL MYOMERE5 TOTAL MYOMERE5

Ophil'ht/ws lIIel

16 " ~: 12 175 178 180 182 184 186 ISB 169 11:1 /. /. 1Il TOTAL MYOMERES

16" Mlll'Ophis p/atllrh!l/ldw, " 1/·4 " Ophidlfh US lIeellut US 10 I"" r1 r1 IS 1040 142 144 146 147 /I·/li1 /. /. 16 TOTAL MYOMERES " " -,10

TOTAl MVOMERES

126 \26 130 \32 134 136 138 \40 \4\ In /. /. Jlj,'OdIlIlO)lh j, IT/Wilt iji.,. TOTAL MYOMERES "'58~ ~

141 14'2 \44 146 \48 ISO 152 \54 156 158 lbO 162 22 /. /. TOTAL MYOMERES 20

12"

('u//ee/W/lls S)I_ n-'! 139 140 142 14' 146 /. 1 c::::J 'TOTAL MYOMERES 182183 j, /. TOTAL MYOMERES t.<'Ill((rcl",s edir"r

Aplerichl"s k"lIItolli : -1I·lli J1---, _ ~~ ~I IJl IJ8 140 lH 144 146 148 150 139 140 142 144 146 148 150 /. /. j TOTAL MYOMEIl:ES TOTAL MYOMERES

Figure 33. Distribution of total myomeres in 11 species of ophichthid leptocephali (Apterichtus ansp, represented by only one specimen, not included). Numbers in vertical scales represent numbers of larvae. Graphs smoothed by moving average of three. Pointers indicate actual ranges. Shaded portion of Ophichllrlls ace/la/us graph refers to larvae with dorsal-edge pigment (see O. acel/atus discussion). 482 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Table 15. Comparison of larval and adult characters in seven ophichthid genera

Genus Larval Characters Adult Characters Ahlia Mildly swollen gut Moderately deep body" Scattered pigment along midline Wide-based pectoral fin Scattered pigment along gut High dorsal and anal fins Myrophis Mildly swollen gut Moderately deep body" Sporadic spots along midline Wide-based pectoral fin Scattered pigment along gut High dorsal and anal fins Ophichlhus Mildly swollen gut Deep bodyt Scattered pigment along midline Narrow-based pectoral fin Gut pigment on and between loops Low dorsal and anal fins PisodO/lopllis Undulating gut Moderately slender body:!: Sporadic pigment along midline Narrow-based pectoral fin Gut pigment on and between loops Low dorsal and anal fins Callechelys Looped gut Moderately slender body:!: Sporadic pigment along midline No pectoral fin Gut pigment on and between loops Low anal, high dorsal fin Lelharchus Looped gut Moderately slender body:!: Sporadic pigment along midline No pectoral fin Gut pigment on and between loops No anal, high dorsal fin A p/erichlus Strongly-looped gut Elongate body§ No midline pigment No pectoral fin Gut pigment only on peaks No dorsal or anal fin t Body depth 15 to 25 in TL. Body depth 25 to 35 in TL. :!: Body depth 35 to 47 in TL. § Body depth 47+ in TL.

minor spots or 15 of equal intensity. Pseudo- The nature of larval pigmentation is myrophis nimius larvae should be recogniz- related to the degree of gut swelling. From able by a "myrophine opisthonephros" and genera with mildly swollen guts to those with high myomere counts. Echiophis larvae strong loops there is a tendency for the pig- should be recognizable by their low myo- ment to change from a generalized, scattered mere counts (combined with a non-resem- pattern of streaks to a consolidated pattern blance to A pterichtus-Ichthyapus larvae of larger, bolder, more complex spots. Ahlia, which also have low counts). Myrophis and Ophichthus larvae (all with Although all ophichthid leptocephali are mildly swollen guts) are characterized by a characterized by looped or swollen guts, the pigment pattern consisting of small, scattered degree to which this character is developed streaks along the midline, anal fin base and varies among genera. The myrophine genera gut. Apterichtus larvae (with strongly looped Ahlia and Myrophis and the ophichthine guts) lack pigment along the midline, lack genus Ophichthus are characterized by mildly pigment along the anal fin base and have gut swollen guts. Apterichtus, by contrast, has pigment restricted to the dorsal surface of carried this character to the highest degree each peak. A progression of this pigment by having a strongly festooned gut. The consolidation is observable in the intervening other genera described in this paper display genera Pisodonophis, Callechelys and Leth- intermediate development of gut looping and archus. the descriptions proceed from mildly swollen The degree of development of gut looping to strongly looped. and pigmentation in larvae is related to cer- FAHAY AND OBENCHAIN: OPHICHTHID LEPTOCEPHALI 483 tain external features in adults. Larvae with same phenomenon probably applies to eel mildly swollen guts and scattered pigment leptocephali. patterns are the young stages of eels with Third, occasional leptocephali probably well-developed fins and relatively thick bod- do metamorphose and settle in areas unsuited ies. Larvae with strongly looped guts and to the adults. The lack of suitable ecological bold, consolidated pigment patterns are the requirements for adults is more to blame for young stages of eels with reduced (or no) the nonestablishment of a species in a cer- fins and relatively elongate bodies. Between tain area than is the failure of larvae to these extrcmes, there is an observable pro- drift into the area. For example, of nine gression of larval and adult characters which species in the ophichthid genera Ophichthus, are summarized in Table 15. Bascanichlhys, Echiophis and Lelharchus After seeing this relationship between lar- which are recorded from Florida, only one val and adult characters, it should be possible is also present in the Bahamas (Gilbert, to predict some characters in undescribed 1972), this despite the conspicuous presence larvae based on adult characters. In the of larvae in most oceanic plankton collections genera A prognathodon, Bascanichthys, My- and the proximity of the latter islands to the richthys and Caralophia, for example, we mainland. would expect the larvae to display guts Several currents probably carry leptoceph- looped to a degree equaling or exceeding the ali into Atlantic coastal waters from out- looping in Callechelys larvae and to have side areas where many ophichthid species are consolidated pigment patterns. Leptocephali known to occur. The Florida Current and of Aplatophis, Quassiremus, Mystriophis and Gulf Stream may carry waifs from the Gulf PseudmnyrOIJhis would be expected to have of Mexico and Caribbean and the North mildly swollen guts and to have more scat- Equatorial Current may transport leptoceph- tered pigment patterns. ali from as far away as West African waters. Horn (1972) has suggested that ZOOGEOGRAPHY AND DRIFT widely separated adult populations of ariommid fishes maintain genetic continuity by Various species of leptocephali are often exchanging larvae across the Atlantic: east captured outside the known range of the to west via the North Equatorial Current and adults. One of the confusing results of this is west to east via either the Equatorial Under- that local collections include larvae which current or North Atlantic Drift. This trans- cannot be linked to adults known from the oceanic larval drift is presumably also pos- area. Several factors account for the presence of leptocephali in areas where corresponding sible with leptocephali, especially considering adults do not exist. First, like larvae of other their abilities to delay metamorphosis. teleosts, a certain percentage of leptocephali is subject to thc caprice of current velocities ACKNOWLEDGMENTS and must ultimately be lost after being car- We thank Dr. and Mrs. 1. E. Bohlke of the ried beyond the geographic limits of the pop- Academy of Natural Sciences at Philadelphia for ulation. Second, eel leptocephali are uniquely allowing us to examine their files of vertebral in- adapted for an extended pelagic existence formation. Our initial groupings of ophichthid (which compounds the first factor). In the leptocephali would have been meaningless without their supporting data. We thank Dr. C. R. Futch of case of the European eel (Anguilla anguilla), the Marine Research Laboratory, St. Petersburg, this pelagic period lasts 3 years. It has been Florida, for loaning juvenile ophichthids, Dr. T. shown that metamorphosis and settlement of W. McKenny of the Northeast Fisheries Center, larval acanthurids (Breder, 1949) and some Narragansett, Rhode lsland, for loaning larval specimens collected during the MARMAP OTP gastropod veligers (Scheltema, 1956) can cruise in 1972, Dr. R. H. Rosenblatt, Scripps be delayed in the absence of an environment Institution of Oceanography, for allowing us ac- where postlarval survival is possible and the cess to cleared and stained ophichthid material, and 484 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

J. E. Cooper of the University of Maryland's 1966. The descriptions of three new Natural Resources Institute for caIling our at- eels from the tropical west Atlantic. Proc. tention to the Myrophis punc/alus ]eptocephalus Acad. Nat. Sci. Phi]a. 118: 9]-]08. caught in the Chesapeake Bay. We have benefited 1968. A new species of ophichthid eel from correspondence with Drs. P. H. J. Castle, genus Verma from the west Atlantic, with Victoria University of Wellington, New Zealand, comments on related species. Notu\. Nat. D. M. Dean, University of South Alabama, J. E. 415: 1-12. McCosker, California Academy of Sciences, and ---, and J. C. Briggs. 1954. Ca/lechelys D. G. Smith, the Marine Biomedical Institute, cliiii, a new ophichthid eel from the Gulf of Galveston, Texas. Drs. S. H. Weitzman and E. A. California. Stanford lchthyo\. Bu]l. 4: 275- Lachner of the U.S. Nationa] Museum, Division of 278. Fishes, and Dr. M. W. Dick of Harvard's Museum ---, and C. C. G. Chaplin. 1968. Fishes of of Comparative Zoology provided X-rays of types the Bahamas and adjacent tropical waters. for vertebral analysis. From the Sandy Hook Livingston Publ. Co., Wynnewood, Pa, xxxii Laboratory staff, we thank Dr. A. W. Kendall for + 771 pp. statistical assistance and helpful discussions on ---, and C. R. Robins. 1959. The characters larval specialization and A. Wells for photo- and synonymy of the western Atlantic snake graphing and printing the figures. Finally, we eel, Ophichthus opllis Linnaeus. Natu!. Nat. thank Drs. E. H. Ahlstrom and D. G. Smith for 320: 1-9. reviewing the manuscript and offering many he]p- ---, and D. G. Smith. 1968. A new xeno- fu] suggestions. congrid eel from the Bahamas, with notes on other species in the family. Proc. Acad. Nat. Sci. Phila. 120: 25-43. LITERATURE CITED Breder, C. M., J r. 1949. On the taxonomy and Backus, R. H. 1957. Northern record of the the postlarval stages of the surgeonfish, snake eel Ophich/hus gomesi (Castlenau). ACWllhll/'Us hepatlls. Copeia ] 949: 296. Copeia ]957: 61. Briggs, J. C. ]958. A list of Florida fishes and their distribution. Bull. F]a. State Mus., BioI. Blache, J. 1963. Note pr6]iminaire sur les larves leptocephales d'apodes du Gulfe de Guinee Sci. 2: 223-3]8. Castle, P. H. 1. 1965. Ophichthid leptocephali (Zone Sud). Cah. O.R.S.T.O.M., Oceanogr. 5 in Australasian waters. Trans. R. Soc. N.Z., (Ser. Pointe-Noire III): 5-23, 32 pIs. Zoo\. 7: 97-123. 1968. Contribution it la connajssance ]969. An index and bibliography of des Poissons Anguilliformes de la cote occi- eel larvae. Spec. Publ., LL.B. Smith Inst. dentale d'Afrique. Huitieme note: la famille Ichthyo\., Rhodes Univ., Grahamstown, S. des Echelidae. Bull. Inst. Fondam Afr. Noire, Africa 7: 1-121. Ser. A, Sci. Nat. 30: 150]-1539. Cervigon, F. 1966. Los peces marinos de Vene- 197]. Contribution a la connaissance zuela, Vo\. ]. Fundaci6n la Salle de Ciencias des Poissons Anguilliformes de la cote occi- Naturales, Caracas, Venezuela. 436 pp. denta]e d'Afrique. Onzieme note: les genres Clark, J., W. G. Smith, A. W. Kendall, Jr., and Myslriophis et Echiophis (Fam. des Ophich- M. P. Fahay. 1969. Studies of estuarine thidae). Bull. Inst. Fondam Afr. Noire, Ser. dependence of Atlantic coastal fishes. Data A, Sci. Nat. 33: 202-226. Report I: Northern section, Cape Cod to ---, and J. Cadenat. ]971. Contribution a la Cape Lookout. R.V. Dolphin cruises 1965- connaissance des Poissons AnguilIiformes de 66: Zooplankton volumes, mid-water trawl ]a cote occidentale d'Afrique. Dixieme note: collections, temperatures and salinities. U.S. les genres MyrichlllYs, Bascanichlhys et Bur. Sport Fish. Wildl., Tech. Pap. 28: 1-132. Callechelys (Fam. des Ophichthidae). Bull. 1970. Studies of estuarine dependence Inst. Fondam Afr. Noire, S6r. A, Sci. Nat. of Atlantic coastal fishes. Data Report II: 33: 158-201. Southern section, New River Inlet, N. c., to ---, and L. Saldanha. 1972. Contribution a Palm Beach, F]a. R.Y. Dolphin cruises 1967- ]a connaissance des Poissons Anguilliformes 68: Zooplankton volumes, surface-meter net de la cote occidentale d'Afrique. Douzieme collections, temperatures and salinities. U.S. note: les genres Pisodonophis, Ophich/hllS, Bur. Sport Fish. Wild\., Tech. Pap. 59: ]-97. Bmcllysomophis et Ophisll/'Us (Fam. des Cohen, D. M., and D. Dean. 1970. Sexual matu- Ophichthidae). BuIl. Inst. Fondam Afr. Noire, rity and migratory behaviour of the tropical S6r. A, Sci. Nat. 34: ]27-159. eel, Alzlia egmonlis. Nature 227: 189-190. Bohlke, J. E. 1960. A new ophichthid eel of the Dawson, C. E. 1959. Records of three marine genus Pselldomyrophis from the Gulf of fishes new to South Carolina. Copeia 1959: Mexico. Notu\. Nat. 329: 1-8. 343. FAHAY AND OBENCHAIN: OPHICHTHlD LEPTOCEPHALI 485

Della Croce, N., and P. H. 1. Castle. 1966. Rep. U.S. Comm. Fish Fish. 1888, 16: 581- Leptocephali from the Mozambique Channel. 677. Boll. Mus. lnst. BioI. Univ. Genova 34(211): Kanazawa, R. H. 1952. More new species and 149-164. new records of fishes from Bermuda. Fieldi- Delsman, H. C. 1933. Fish eggs and larvae from ana, Zool. 34: 71-100. Java Sea. No. 21, eel eggs. Treubia 14: 237- 1963. Two new species of ophichthid 247. eels from the western Atlantic. Proc. BioI. Eigenmann. C. H. 1887. Description of a new Soc. Wash. 76: 281-288. species of OphichtllYs (OpMcllthys retro- Lea, E. 1913. Muraenoid larvae from the pinllis) from Pensacola, Fla. Proc. U.S. Nat. "Michael Sal's" North Atlantic deep-sea ex- Mus. 10(613): 116. pedition, 1910. Rep. Sal's N. Atl. Deep Sea ---, and C. H. Kennedy. 1902. The lepto- Exped. 3: 1-48. cephalus of the American eel and other Amer- McCosker, J. E. ] 973. The osteology, classifica- ican leptocephali. Bull. U.S. Fish Comm. tion, and relationships of the eel family 21(1901): 8]-92. Ophichthidae (Pisces, Anguilliformes). Un- Eldred, B. 1966. The early development of the publ. Ph.D. Thesis, Univ. Calif., San Diego. spotted worm eel, Myrophis plllle/a/IIS LUtken 289 pp. (Ophichthidae). Fla. Bd. Conserv. Mal'. Lab., 1974. A revision of the ophichthid eel Leafl. Sel'. 4, Part 1: 1-13. genus Le/harchus. Copeia 1974: 619-629. Fahay, M. P. 1975. An annotated list of larval 1977. The osteology, classification, and and juvenile fishes captured with surface- relationships of the eel family Ophichthidae. towed meter net in the South Atlantic Bight Proc. Cal. Acad. Sci. Ser. 4, Vol. 41, No. I: during four RV Dolphin cruises between May 123 pp. 1967 and February 1968. NOAA Tech. Rep. ---, and R. H. Rosenblatt. .1972. Eastern NMFS SSRF 685: 1-39. Pacific snake-eels of the genus Callechelys Fowler, H. W. 1938. The fishes of George (Apodes: Ophichthidae). Trans. San Diego Vanderbilt South Pacific Expedition, 1937. Soc. Nat. Hist. 17: 15-24. Monogr. Acad. Nat. Sci. Phila. 2: 1-349, 12 Moser, H. G., and E. H. Ahlstrom. 1974. Role pis. of larval stages in systematic investigations of .1944. The fishes. Pages 57-529 in marine teleosts: the Myctophidae, a case Results of the Fifth George Vanderbilt Ex- study. U.s. Fish. Bull. 72: 391-413. pedition (1941) (Bahamas, Caribbean Sea, Orton, G. L. 1962. Corrected list of published Panama, Galapagos Archipelago and Mexican vertebral counts for certain eels (Apodes). Pacific Islands). Monogl'. Acad. Nat. Sci. Copeia 1962: 664-665. Phila. No.6. Randall, J. E., and C. R. Robins. 1966. Acan/Iz- Gilbert, C. R. 1968. A mass inshore movement enchelys spillicauda Norman, valid West of fishes on the Florida coast. Q. J. Fla. Indian species of the snake-eel genus Ophich- Acad. Sci. 31: 70-78. thus. Copeia 1966: 610-611. 1972. Characteristics of tbe western Richardson, S. L. 1974. Eggs and larvae of the Atlantic reef-fish fauna. Q. 1. Fla. Acad. Sci. ophichthid eel, Pisodollophis cruentifer, from 35: 130-144. the Chesapeake Bight, western North Atlantic. Ginsburg,1. 1951. The eels of the northern Gulf Chesapeake Sci. 15: 151-154. coast of the United States and some related Rosenblatt, R. H., and 1. E. McCosker. 1970. species. Tex. J. Sci. 3: 431-485. A key to the genera of the ophichthid eels, Gronovius, L. T. 1763. Zoophylacii Gronoviani with descriptions of two new genera and three fasciculus primus exhibens animalia quadru- new species from the eastern Pacific. Pac. Sci. peda, amphibia atque pisces, quae in museo 24: 494-505. suo adservat. Lugduni Batavorum, 136 pp. Scheltema, R. S. 1956. The effect of substrate Horn, M. H. 1972. Systematic status and aspects on the length of planktonic existence in of the ecology of the elongate ariommid fishes N assarius obsoleta. BioI. Bull. Ill: 312. (suborder Stromateoidei) in the Atlantic. Schmidt, E. J. 1913. On the identification of Bull. Mal'. Sci. 22: 537-558. muraenoid larvae in their early ("Prelepto- Jones, S., and V. R. Pantulu. 1955. On some cephaline") stages. Medd. Kimm. Havunders., ophichthyid larvae from the Indian coastal Sel'. Fisk 4: 1-13, 1 pI. waters. Indian 1. Fish. 2: 57-66. Schroeder, W. C. ]941. Notes on two fishes, Jordan, D. S., and B. M. Davis. 1892. A pre- Ophich/hus ocellatlls and Paranthias furdfer, liminary review of the apodal fishes or eels taken off Pensacola, Florida. Copeia 1941: inhabiting tbe waters of America and Europe. 45. 486 BULLETIN OF MARINE SCIENCE, VOL. 28, NO.3, 1978

Springer, V. G., and K. D. Woodburn. 1960. An University Zoological Museum at Upsala. ecological study of the fishes of the Tampa Almqvist & Wiksell, Upsala, 53 pp., 5 pIs. Bay area. Fla. Bd. Conserv. Mar. Lab., Prof. Pap. Ser. I: ]-104. DATE ACCEPTED: June 10, ]977. Storey, M. H. 1939. Contributions toward a revision of the ophichthyid eels. J. The genera ADDRESS: U.S. Department of Commerce, National Callechelys and Bascanichthys, with descrip- Oceanic and Atmospheric Administration, National tions of new species and notes on Myrichthys. Marine Fisheries Service, Northeast Fisheries Stanford Ichthyol. Bull. 1: 61-84. Center, Sandy Hook Laboratory, Highlands, New Stromman, P. H. 1896. Leptocephalids in the Jersey 07732.

Leptocephali of the Ophichthid Genera &lt;I&gt;Ahlia

Leptocephali of the Ophichthid Genera <I>Ahlia