<I>Helcogramma</I>
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BULLETIN OF MARINE SCIENCE, 38(2): 313-354. 1986 REVISION OF THE TRIPTERYGIID FISH GENUS HELCOGRAMMA, INCLUDING DESCRIPTIONS OF FOUR NEW SPECIES Patricia E. Hadley Hansen ABSTRACT Helcogramma includes 12 species: H. billi n. sp., H. capidata Rosenblatt, 1960, H. chica Rosenblatt, 1960, H. decurrens McCulloch and Waite, 1918, H. el/ioti (Herre, 1944), H. fuscopinna Holleman, 1982, H. hudsoni (Jordan and Seale, 1906), H. obtusirostris (Klunzin- ger, 1871), H. rhinoceros n. sp., H. springeri n. sp., H. steinitzi Clark, 1979, and H. striata n. sp. Helcogramma trigloides is regarded as a species inquirendum; no specimens of this species were found. The four new species are figured in whole lateral view. Ail species are figured in detailed head views to show characteristics of cephalic sensory canals (dorsal and ventral). My study confirms that all members of the family Tripterygiidae share a single specialization: Loss of the posteriormost spine of the second dorsal fin. Members ofthe genus Helcogramma share the following character: A single lateral line, composed of 12-37 pored scales curving down from the posttemporal bone, behind the pectoral fin and continuing along the midline of the body. Some characters of the osteology of Helcogramma are discussed and figured in the diagnosis of the genus. Members of the genus Helcogramma McCulloch and Waite comprise small species (less than 60mm SL adult size) that live on rock surfaces and under ledges (Zander and Heymer, 1970; 1976; pers. obs.). They are common in depths less than 10m, although on the Zululand Coast they are common at depths up to 18 m (Holleman pers. comm.). Helcogramma species spawn on algal-covered rock surfaces and the larvae are occasionally taken with adults (Hansen, pers. obs.). Although tripterygiid fishes are ubiquitous, they are often overlooked or given scant attention in field guides and checklists. This is probably due to their small size and cryptic coloration. However, the males of most tripterygiid species display bright nuptial coloration, and can easily be seen during the spawning season. The 12 species of Helcogramma occur mainly in the Indo Pacific (one species is found in the Southeastern Atlantic) and they compose the second largest genus oftripterygiid fishes. Enneapterygius, also Indo Pacific in distribution, comprises more than 20 species (Holleman, pers. comm.). Enneanectes, from the Atlantic, was revised by Rosenblatt (1960) and includes 5 species. No other tripterygiid genera have been revised. The genus Helcogramma is in need of definition. Studies of Helcogramma have been regional (De Beaufort and Chapman, 1951; Schultz, 1960; Clark, 1980; Holle- man, 1982). Helcogramma was first described (McCulloch and Waite, 1918) from a "single somewhat damaged specimen" of the type species, H. decurrens. The description was one short sentence and it did not clearly define the genus. Ro- senblatt defined Helcogramma (in Schultz, 1960) using a combination of char- acters: single lateral line, single anal spine, palantine teeth, and pelvic rays united by a membrane for part of their length. Although this definition is applicable to all described species of Helcogramma, it also includes members of an undescribed genus (Rosenblatt, 1959) and several species placed in the genera Enneapterygius and Tripterygion. Therefore I am redefining the genus to exclude all other genera, and include descriptions of all species I recognize as Helcogramma. 313 314 BULLETIN OF MARINE SCIENCE, VOL. 38, NO.2, 1986 COMOOM OMOOOO OM 0'<1' -("f"'j("'l"'jf"-.t"--O M'<I''''COM OMOIDO'<l' 00 C!-: 00 '-0 f'f"'I-\OO 00000\ 0\0\0\0000\ 00 COCO 00000"": NNNN •....• ----N- NN -- -NNNNN '" - o N •.... - N ---Nf'f"'I ••••• '<1' COCOMOO OM 00 ,,",OIDOOO COCOooNO "' •.... 0'" 00"'000 -----cicici"":""': 00 0\0\ ------""':""':0""":""":""": '<1'- --("'-.1- ---N~ r--- -N - t'f'l --"=t N- '<I' ooIDOOM •....MOOMO OlD ,,","'O\MOO ooooOooM IDMOOMID 000 •....•....000000 ....; -----"";",,;-.t,,,,;-.t "";-.t-.t.n.n-.t------ "";,..,j ------"";"";,,,,;,,,,;-.t-.t -0-- \0 N--- -ID M N HANSEN: REVISION OF THE GENUS HELCOGRAMMA. INCLUDING FOUR NEW SPECIES 315 •.•.•0 0001- •.•.•011"I001- \00 00\0\0 OOIt'\NIi'\OO\O 0""; 0000 do.....;.....:;~o\ NN NNNN NNNN-- ... N N N N l- \0 \0 f'l""IN-V'\("f"')\C)f'- ~,., I!! 0 NNN- •.... 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INCLUDING FOUR NEW SPECIES 317 <'\0 ...,00-00<,\ 000 '<1'00100<'\ ." 0\""; "";"":00\0"": -N NNN-NN .., N N- N N 00-- N ...,00...,-N ~ e» - 0 OO--"'f"I"'I~f"I"'I- N «'"e <'\N- 00 00 •...NOOO<'\ q"'!-- S~~::::=0-0-<'\00<'\ -- •... 0- "l:tMOOI.t"'l-N '2 N- O - "2'" :c =: -00-0 f- N 000 r--N...,OO<,\ ""0 000-<'\00<'\ ," ,..;..,,: ,..;,..;,..;,..;,..;..,,:------ ><> > <'\ '2 >< 0 > r-N-ooNO\ -N '"'0 e X <'I- 0 ~ ..., 00-0\"'- X X N ,0= a O/j oS '"O 2 !iboS .~ v Po ..c::Z oS V ~ V ~ ~ (I). oS --c:: ~ e ~ oS ~ "0 '" oS =~§ v "~ §EoS,s,<g,o .l:l"O " u:~ ~ I c:: E .a 5 .9= [ c"'oSC::oS~ oS~ E Vl '1: v C oS co = 0 f-<~:.:;;l~.. ~"OtjO:j U «i'~Ou rl:.a; 0;:'; cc::-C::" .>o::::;!;"~ "'~ v 0'" .ci S ci:: ;8;--:'::e[g o::s .:soS ~:.:::..c::~o~ v 'S 'C 0- ~.~ :.c ~ d)"O • :0oS '" (I)~c.::f-<ll..ZZ(l)Z !-< ~ 318 BULLETIN OF MARINE SCIENCE, VOL. 38, NO.2, 1986 MATERIALS AND METHODS Measurements were made with dividers and metric ruler using the methods of Hubbs and Lagler (1958), with the exception of the following: Seventh pectoral ray length was measured from the distal end ofthe pectoral radial adjacent to the seventh pectoral ray (counting from the bottom) to the distal tip of the ray; upper jaw length was measured from the anterior margin of the tip of the upper lip to the posteriormost edge of the maxilla; second dorsal base length was measured from the small bump created by the distal pterygiophore anterior to the fourth dorsal spine base (not including the membrane following); third dorsal base length was measured from the small bump created by the distal pteryg- iophore anterior to the first segmented dorsal ray, to the last segmented dorsal ray base (not including the membrane following); distance from the pectoral to anal spine (P I-anal fin) was measured as the distance from the base of the left first pectoral ray (counting from the bottom) to the anal spine. Measurements and counts were made on the left side of specimens whenever possible. The following abbreviations for measurements were used: HL = head length; SL = standard length; ML = upper jaw length; and N = number of specimens. In the measurement section of each species description, the measurements are recorded as %SL, and are given as: mean %SL followed by the range of %SL in parentheses. In the material examined sections, SL in mm is recorded in parentheses after the number of males, females, or total number of specimens. Statistical methods follow Sokal and Rolf (1969). Linear regression equations and their correlation coefficients were computed using Minitab statistical computing system (Ryan et aI., 1976). Counts of dorsal-, anal-, caudal-, and pectoral-fin elements were taken from the whole preserved specimens whenever possible (Table la, b). If there were dorsal or anal elements missing or broken on the specimen, it was radiographed, and these counts were taken from the radiographs. The last dorsal and anal fin rays were often divided to the base, and these were counted as a single element if they were attached to a single pterygiophore. The anteriormost vertebra bearing a well-developed haemal spine is the anteriormost caudal ver- tebra. Counts of caudal-fin elements are reported as a formula: dorsal procurrent rays + segmented rays + ventral procurrent rays. The number of cephalic sensory pores in Helcogramma (Fig. I) is difficult to standardize. I have considered only large adult specimens (> 25.0 mm SL) in describing pore patterns because the pore systems become more branched and the pore number increases during ontogeny but are fully developed by about 25 mm. I have used the two anteriorly extending central canals from the occipital canal as references, and designated species shown in Figures a, c, f, k, and I as "simple"; b, d, e, h, and i as "moderately complex"; and g andj as "complex." Although this character is useful in a relative sense, it should be noted that individual variation is great between and among populations in a species.