Anglerfishes of the Genus Chaenophryne (Family Oneirodidae)
Total Page:16
File Type:pdf, Size:1020Kb
SYSTEMATICS AND DISTRIBUTION OF CERATIOID ANGLERFISHES OF THE GENUS CHAENOPHRYNE (FAMILY ONEIRODIDAE) THEODORE W. PIETSCH 1 Abstract. The ceratioid anglerfish genus Regan (1925) established the genus Chaeno- of the Oneirodidae is revised Chaenophryne family phryne with the description of C. longi- on the hasis of all known material. Of the 18 ceps based on 14 specimens, only one of available names, four are recognized as species. which the The five nominal forms, Chaenophryne longiceps, actually represented type spe- C. crossota, C. bicornis, C. quadrifilis, and C. cies. The remaining 13 specimens were crenata, previously forming the C. longiceps- included in descriptions of 13 new species and C. of the C. are group, haplactis draco-group, introduced by Regan and Trewavas (1932): considered synonyms, taking the oldest available C. bicornis, C. crenata, C. quadrifilis, C. name, C. longiceps. The C. longiceps-grovp, now- C. C. atriconus, C. being monotypic, is not recognized. The C. draco- haplactis, parviconus, group, however, is retained to include larvae and columnifera, C. melanodactylus, C. macrac- males from those of C. easily distinguished tis, C. melanorhabdus, C. pterolophus, C. but not divisible into smaller taxonomic longiceps fimbriata, and C. ramifera. Prior to Bertel- units. Included in the C. draco-group are three sen's 1951 on the ( ) monograph Ceratioidei, species based on metamorphosed females: C. four additional forms were described: C. draco, C. melanorhabdus, and C. ramifcra. Chaenophryne parviconus, C. atriconus, C. columni- crossota Beebe, 1932; C. draco Beebe, 1932; fera, C. macractis, and C. melanodactylus are C. intermedia Belloc, 1938; and C. pads considered synonyms of C. draco. Chaenophryne Koefoed, 1944. The total number of melanorhabdus with its junior synonym, C. nominal species is thus 18, 14 of which were pterolophus, is resurrected from synonymy and based on one or two adolescent female given specific status. Chaenophryne pads is a synonym of C. ramifera. The tentative distri- specimens less than 20 mm standard length, bution of each species is plotted, evolutionary none on more than nine specimens, and relationships are discussed, and a key to the only one represented by a specimen larger species of the genus is provided. than 24 mm standard length. INTRODUCTION From an examination of the extensive larval material in the DANA Collections, includes The genus Chaenophryne Bertelsen (1951) was able to divide the globose, bathypelagic anglerfishes, easily then known material of Chaenophryne into from members of allied separated genera two species-groups based on the inner pig- the absence of an by sphenotic spines, ment layer and number of pectoral fin-rays. that is concave operculum only slightly Within the C. longiceps-group he tenta- posteriorly, and peculiar, highly cancellous tively recognized five species: C. longiceps, bones (Bertelsen, 1951:109; Pietsch, 1974a). C. quadrifilis, C. bicornis, C. crenata, and the C. 1 C. crossota; within draco-group Museum of Comparative Zoology, Harvard Universitv. three species: C. draco, C. parviconus, and Bull. Mus. Comp. Zool., 147(2): 75-100. May, 1975 75 76 Bulletin Museum of Comparative Zoology, Vol. 147, No. 2 Tahle 1. Reallocation of nominal forms of CHAENOPHRYNE. longiceps Regan, 1925 crossotus Beebe, 1932 longiceps-groug of bicornis Regan and Trewavas, 1932 longiceps Regan, 1925 Bertelsen, 1951 crenata Regan and Trewavas, 1932 quadrifilis Regan and Trewavas, 1932 haplactis Regan and Trewavas, 1932 draco Beebe, 1932 parviconus Regan and Trewavas, 1932 atriconus Regan and Trewavas, 1932 columnifera Regan and Trewavas, 1932 draco Beebe, 1932 melanodactylus Regan and Trewavas, 1932 draco-group of macractis Regan and Trewavas, 1932 Bertelsen, 1951 melanorhabdus Regan and Trewavas, 1932 melanorhabdus Regan and pterolophus Regan and Trewavas, 1932 Trewavas, 1932 ramifera Regan and Trewavas, 1932 fimbriata Regan and Trewavas, 1932 intermedia Belloe, 1938 ramifera Regan and Trewavas, 1932 parts Koefoed, 1944 C. ramifera. Chaenophryne fimbriata and side whenever possible and rounded to the C. intermedia were considered synonyms of nearest 0.1 mm. To insure accurate fin-ray C. ramifera and all remaining available counts, skin was removed from the pectoral names were placed in the synonymy of C. fins and incisions were made to reveal the parviconus. rays of the dorsal and anal fins. Illicium In the present paper it is shown that length is the distance from the articulation the available female material of Chaeno- of the pterygiophore of the illicium and the phryne represents four well-defined species illicial bone to the dorsal surface of the (Tabic 1): C. longiceps, represented by 33 escal bulb, excluding escal appendages. specimens, collected from all three major Terminology used in describing the various oceans of the world; C. draco, represented parts of the angling apparatus follows by 46 specimens, also of world-wide dis- Bradbury (1967). Definitions of terms tribution; C. melanorhabdus, 23 .specimens, used for the different stages of develop- apparently restricted to the continental ment follow those of Bertelsen (1951:10- slope of western North America; and C. 11). Complete locality data for primary ramifera, 15 specimens of world-wide dis- type material is entered in the synonymies. tribution. The separation of these species Drawings were made with the aid of a is based almost entirely on the morphology Wild M-5 Camera Lucida. of the esca. Significant differences exist, Since nearly all the available collections however, in the width of the escal bulb, the of Chaenophryne were made with non- length of the illicium, jaw tooth counts, closing nets, the actual depth of capture is and fin-ray counts. unknown. For those species represented Despite a greater than four-fold increase by sufficient material, vertical distributions in material since Bertelsen's (1951) re- were analyzed by a procedure similar to vision, males can be separated into only that used by William H. Krueger (un- two taxonomic units corresponding to C. published manuscript) for determining longiceps and the C. f/raeo-group. depths of capture of Idiacanthus, and out- lined see also by Cibbs ( 1969; Pietsch, METHODS AND MATERIALS 1974a). Station data were taken from Standard lengths (SL) were used through- Schmidt (1929), Carlsberg Foundation out. Measurements were taken on the left (1934), and unpublished data for VELERO Anglerfishes of the Genus Chaenophryne • Pietsch 77 IV cruises of the University of Southern LACM: Natural History Museum of Los California. For each trawl, the number of Angeles County. hours at depth was multiplied by the area MCZ: Museum of Comparative Zoology, of the mouth of the net. The number of Harvard University. meter-hours for each depth interval, and MNLR: Musee d'Histoire Naturelle de La the number of specimens caught at each Rochelle. depth interval were tabulated and expressed NYZS: New York Zoological Society. as a percentage of total for comparison. OSUO: Oregon State University, Depart- When the percentage of specimens caught ment of Oceanography, Corvallis. at any depth is considerably greater than ROM: Royal Ontario Museum, Toronto. the percentage of meter-hours at that depth, SU: Stanford University (collections it may be assumed that this represents a now housed at the California region of concentration. The reverse indi- Academy of Sciences, San Fran- that cisco . cates specimens recorded for that ) depth probably were caught while the net UMML: University of Miami Marine Lab- was being lowered or raised. oratory. Material used for the comparative os- USNM: United States National Museum, teological investigation was cleared and Washington. stained with alizarin red S following the UW: Fish Museum, University of trypsin digestion technique (Taylor, 1967). Washington, Seattle. In many cases, dissections were made of ZMB: Zoological Museum, University of uncleared specimens to confirm observa- Bergen. tions made on cleared specimens. Bone ZMUC: Zoological Museum, University of terminology follows Pietsch (1974a). Copenhagen. The generic diagnosis for females is based largely on osteological evidence pre- OSTEOLOGY sented elsewhere (Pietsch, 1974a). Generic The osteology of Chaenophryne has been and species descriptions are based on 116 previously described in detail and com- metamorphosed females ranging from 11.0 with that of other oneirodid to 170.0 and tooth pared genera mm ( morphometries jaw (Pietsch, 1974a; C. melanorhabdus mis- counts on specimens 20.0 mm and larger). identified as C. Not mentioned Males and larvae were described by parvieonus). before, however, is the conspicuous, honey- Bertelsen (1951:110-116). Study material comblike network of ridges that partially is deposited in the following institutions: form many of the bones of Chaenophryne. AMNH: American Museum of Natural These highly cancellous bones include Historv, New York. those that provide the dorsal surface of the BMNH: British Museum (Natural History), cranium, excluding those that form the London. illicial trough: the dorsal surface of the BOC: Bingham Oceanographic Collec- frontals, the sphenotics, pterotics, parietals, tions, Peabody Museum of Natural and posttemporals; portions of the mandib- History, Yale University. ular arch: the maxillaries, dentaries, and IOM: Institute of Oceanology, Academy articulars; and parts of the opercular ap- of Sciences of the USSB, Moscow. paratus: the operculum, suboperculum, and IOS: Institute of Oceanographic Sci- preoperculum.