SCOPELARCHIDAE 3°7 



Family Harpadontidae 



Genera Harpadon Le Sueur, Bathysaurus Giinther 



Family SYNODONTIDAE 

 Genera Synodus (Gronovius) Scopoli, Trachinocephalus Gill, Saurida Cuvier and Valen- 

 ciennes, Xystodus Ogilby. 



The Family SCOPELARCHIDAE 

 The first known fish of this family was described by Alcock (1896, 1899) under the name Scope- 

 larchus guentheri. 1 It was taken by H.M. Indian Marine Survey Steamer ' Investigator ' while trawling 

 between depths of 180 and 217 fathoms off Colombo, Ceylon. Observing that the fish '...is a 

 remarkable generalized form of Scopeloid, showing affinities with Saurus, Chlorophthahmis, Scopelus, 

 Odontostomus and Paralepis\ Alcock (1896) placed it in the family Scopelidae, group Scopelarchina. 



' Valdivia ' took twelve specimens of scopelarchids at various stations in the Atlantic, Indian and 

 Southern Oceans. These were described by Brauer (1902, 1906) as Dissomma atiale and placed in 

 the family Scopelidae. Roule (191 6, 1919), having examined seven scopelarchids taken off the 

 Azores during the cruises of ' Princesse Alice ', described them as a new species, Odontostomus perar- 

 matus, of the family Odontostomidae. However, Odontostomus Cocco (amended to Evermannella by 

 Fowler (1901), on account of Odontostomus Cocco, 1838, being a homonym of Odontostomus Beck, 

 1837, a molluscan genus) is quite distinct from Scopelarchus (see below). 



Regan (191 1), in setting out the classification of the Iniomi, defined the family Scopelarchidae and 

 placed it in the suborder Alepisauroidea. Then Parr (1928) pointed out that Regan had included both 

 Evermannella and Scopelarchus (= Dissomma) in the Scopelarchidae, and that the diagnosis of the 

 family was based on a study of Evermannella hyalina. Parr showed clearly that Scopelarchus and Ever- 

 mannella are so distinct as to warrant separation into different families : he was thus able to give the 

 first critical diagnosis of the Scopelarchidae. In a later paper (Parr, 1929), this diagnosis was extended 

 to include findings from osteological studies. Furthermore, in the 1929 paper a new genus and species, 

 Scopelarchoides nicholsi, was described, the type and a paratype being taken by ' Pawnee ' off the west 

 coast of Mexico. Additions to this description are to be found in a later paper (Parr, 193 1 a) in which 

 three more specimens are recorded, one from the Gulf of California, one off the west coast of Central 

 America and one from a locality in the Pacific Ocean. 



A further new species, Scopelarchus elongatus, was described by Norman (1937) from an individual 

 taken north-east of Kerguelen Island by the B.A.N. Z. Antarctic Research Expedition. This was fol- 

 lowed by Chapman's (1939) proposal of a new genus and species, Neoscopelarchoides dentatus, the 

 holotype coming from the central part of the Gulf of Alaska. Lastly Mead and Bohlke (1953) have 

 described Scopelarchus linguidens from three juvenile individuals taken off northern Japan. 



The Discovery material contains two new species and a large larval scopelarchid, descriptions of 

 which, together with a fuller account of Norman's species elongatus, now follow. But to anticipate a 

 later section, it must be added, that the study of these individuals has led me to conclude that the 

 scopelarchids can be divided into two well-marked genera, Scopelarchus Alcock and Neoscopelarchoides 

 Chapman. Synonymies will be discussed on p. 312-14. 



Scopelarchus cavei sp.n. 

 (Fig. 1 and PL XIX, figs, 5, 6.) 

 Holotype. A specimen 70 mm. in standard length taken by R.R.S. 'Discovery II' in a young fish 

 trawl, hauled obliquely between 500 m. and the surface, at station 1585: oo° 06' S, 49 45-4' E., 

 Indian Ocean : about 400 miles north-west of the Seychelles. 



1 In the 1899 publication Alcock gave the specific name as giintheri. 



