TAXONOMY AND DISTRIBUTION OF ROULEINA ATTRITA AND 

 ROULEINA MADERENSIS (PISCES: ALEPOCEPHALIDAE)i 



Douglas F. Markle^ 



ABSTRACT 



Three Atlantic species o{ Xenodermichthys and Rouleina are recognized: X. copei, R. attrita, and R. 

 maderensis. Bathytroctes mollis and B. aequatoris are considered junior synonyms of R. attrita. 

 Anomalopterus megalops is considered incerta sedis. 



Diagnostic characters fori?, attrita are: no photophores, convoluted testes, 43-48 lateral line scales, 

 43-46 preural vertebrae, papillae on body near lateral line, and maturation at a size around 250-300 

 mm standard length. Diagnostic characters for/?, maderensis are: photophores present, lobate testes, 

 50-56 lateral line scales, 47-50 preural vertebrae, papillae usually peripheral to photophores on fins 

 and fin bases, and maturation at a size around 200-250 mm standard length. 



The two species are sharply segregated by depth: 91% of alii?, maderensis were from bottom trawls 

 made between 595 and 1,200 m while 88% ofaUR. attrita were from bottom trawls fished between 1,400 

 and 2,100 m. 



The Alepocephalidae are moderate to large deep- 

 sea salmoniform fishes, most commonly encoun- 

 tered below 1,000 m. In terms of biomass and 

 species diversity, the family is one of the most 

 important in the deep sea. Recent exploratory 

 trawling has discovered commercial concentra- 

 tions of alepocephalids west of the British Isles 

 (Anonymous 1974) and in the northwestern At- 

 lantic (Savvatimskii 1969). Off northwestern Af- 

 rica, Golovan (1974) found about 20 species of 

 alepocephalids and labeled the zone below about 

 1,000 m as "the kingdom of fishes of the family 

 Alepocephalidae." As might be expected in a di- 

 verse group of deep-sea fishes, there are still many 

 problems with identification and nomenclature. 



One group of naked alepocephalids, those with 

 approximately equal and opposite dorsal and anal 

 fins, has been the subject of numerous descriptions 

 and much confusion. Roule (1915) recognized two 

 genera, Rouleina {=Aleposomus of Roule) and 

 Xenodermichthys, the latter distinguished by a 

 greater number (more than 25) of dorsal and anal 

 fin rays. 



The two known species of Xenodermichthys, X. 

 nodulosus and X. copei, have caused few 

 taxonomic problems and are easily diagnosed. 

 Both have photophores arranged approximately 



'Contribution No. 825 from the Virginia Institute of Marine 

 Science. 



^Virginia Institute of Marine Science, Gloucester Point, Va.; 

 present address: Huntsman Marine Laboratory, St. Andrews, 

 N.B. EOG 2X0, Canada. 



Manuscript accepted April 1977. 



FISHERY BULLETIN; VOL. 76, NO. 1, 1978. 



in quincunx on the body and fin bases, two pyloric 

 caeca, and no lateral line scales in adults. Xeno- 

 dermichthys copei has 27-31 dorsal and 26-30 anal 

 fin rays, 46-50 vertebrae, and an unrestricted gill 

 opening; X. nodulosus has 32-33 dorsal and anal 

 fin rays, 50 vertebrae, and a dorsally restricted gill 

 opening which begins at the upper base of the 

 pectoral (Markle 1976). The nomenclature of the 

 Atlantic species, X. copei, has been confused be- 

 cause the oldest of the three available names, 

 Aleposomus copei Gill 1884, was originally de- 

 scribed as: "an Alepocephalid, with the body as 

 well as heads caleless (sic), which I shall describe 

 as Aleposomus copei.'' Grey (1959) and Krefft 

 (1973) have considered A. copei Gill 1884 a nomen 

 nudum, but Gill's ( 1884) sentence clearly refers to 

 an alepocephalid with a naked head and body, and 

 in 1884 that was a sufficient amount of informa- 

 tion to clearly distinguish it from all known alepo- 

 cephalids, with the possible exception of X. 

 nodulosus. In any case the inadequate statement 

 satisfies Articles 11 and 12 of the International 

 Code of Zoological Nomenclature and the name 

 has been used frequently since 1884. Gill's 

 holotype (USNM 33551) was subsequently de- 

 scribed and figured by Goode and Bean (1895). 



The taxonomy of Rouleina is more confused, in 

 part because there are 15 nominal species, many 

 based upon damaged or poorly preserved speci- 

 mens. All known species of Rouleina can be dis- 

 tinguished from Xenodermichthys by having less 

 than 25 anal fin rays, more than two pyloric caeca, 



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