MOSER ET AL.: MYCTOPHIDAE 



239 



in early preflexion stage, elongates to midbody by flexion stage; 

 in postflexion stage pigment above brain, embedded in otic 

 region, lateral to cleithrum, at anteroventral region of liver; one 

 to several dorsal median melanophores and one ventral median 

 melanophore at caudal peduncle. 



Lampanyclus. — Figs. 123. 124; body slender; head deep; gut 

 short in early preflexion stage; during preflexion stage gut length- 

 ens to midbody. body deepens and becomes somewhat robust 

 in most species; pigment above brain in most species; postflex- 

 ion larvae develop trunk myoseptal pigment that increases to 

 cover most of the anterior trunk at transformation; at least 6 

 morphs. L. nohilis-L. parvicaiida-L. oinostigma-L, crocodilus- 

 L. ritteh-L. idostigma: Figs. 123C-E. 124A, B; body and head 

 moderately deep; eyes, jaws, pectoral fins moderate in size; pig- 

 ment may be present at snout, lower jaw. opercle, above gut, 

 anteroventral surface of liver, at dorsal or ventral midline on 

 tail. L. pusillus-L. steinbecki: Fig. 123 A, B; deep, broad body 

 and head, very robust; snout blunt; eyes large; dorsal and anal 

 fins displaced posteriad; pectoral fins moderately large; L. pus- 

 illus heavily pigmented on head, body, pectoral fin base; series 

 along horizontal septum; L. steinbecki with pigment below lower 

 jaw, on opercle. pectoral fin base; series along horizontal septum 

 and embedded pigment on tail in postflexion larvae. L. regalis- 



L. ater. Fig. 1 24C; deep, large head and body; snout elongate, 

 jaws large, teeth well developed, especially at tip of upper jaw; 

 preopercular spines in some species; dorsal and anal fins dis- 

 placed posteriad; pectoral fins moderate to large; pigment may 

 be present at tips of jaws, embedded in snout, at postorbital 

 and opercular regions, pectoral and pelvic fins; spot at adipose 

 fin in L. regalis; one or two dorsal spots in L. ater. Information 

 on L. ater irom H. Zadoretsky (Dept. Zoology, Univ. of Rhode 

 Island, pers. comm.). L. achirus: Fig. 1 24E; body moderately 

 deep; head and jaws large with snout produced into toothy ros- 

 trum; dorsal and anal fins displaced posteriad; pectoral fins mod- 

 erately large; pigment on tips of jaws, embedded in snout, and 

 present at postorbital and opercular regions. L. lineatus-L. cu- 

 prarius: body moderately elongate; snout elongate, jaws large; 

 head pigment as in L. achirus; L. lineatus pigment consists of 

 numerous melanophores along dorsum and ventrum and at base 

 of caudal rays; L. cuprarius has pigment above gut and an ir- 

 regular bar below dorsal fin. Information from H. Zadoretsky 

 (pers. comm.). 



(H.G.M.) National Marine Fisheries Service, Southwest 

 Fisheries Center, P.O. Box 271, La Jolla, California 

 92038; (J.R.P.) The Australian Museum, 6-8 College 

 Street, Sydney 2000, Australia. 



Myctophidae: Relationships 

 J. R. Paxton, E. H. Ahlstrom and H. G. Moser 



THE family Myctophidae has usually been placed in the order 

 Myctophiformes (Iniomi. Scopeliformes) since the work 

 of Regan (191 la), who recognized two suborders, the Mycto- 

 phoidea and Alepisauroidea (ateleopodids, given a third sub- 

 order, are currently placed elsewhere). The families Myctophi- 

 dae and Neoscopelidae have long been considered close relatives; 

 they were placed in one family until 1949 (Smith). Although 

 Greenwood et al. (1966:371) relegated the order to a subordinal 

 level within the Salmoniformes, they pointed out that mycto- 

 phoids. and neoscopelids in particular, possess advanced char- 

 acters that indicate they may be ancestral to the paracanthop- 

 terygian radiation. Paxton (1972:54-55)considered myctophids 

 and neoscopelids most closely related to the Chlorophthalmi- 

 dae. with that evolutionary line of the Myctophoidea arising 

 from an aulopid-like ancestor. Moser and Ahlstrom (1970: 141- 

 142) described the larval similarities in the families Chloroph- 

 thalmidae, Neoscopelidae and Myctophidae. 



Family Relationships 



Rosen (1973, 1982) split ofl" the Myctophidae and Neosco- 

 pelidae as a restricted order Myctophiformes which he consid- 

 ered the primitive sister group of both the Paracanthopterygii 

 and Acanthopterygii; the remaining myctophiform families were 

 placed in a new order Aulopiformes. Matsuoka and Iwai (1983) 

 found cartilage in the adipose fin of only the Myctophidae and 



Neoscopelidae in the five 'iniomous' families they studied. Oki- 

 yama (1974b) studied the relationships of the suborder Mycto- 

 phoidea (sensu Gosline et al., 1966) and based on larval peri- 

 toneal pigment spots and the relationship of abdominal to caudal 

 vertebrae, three familial groups were recognized: Aulopidae- 

 Synodontidae-Bathysauridae, Chlorophthalmidae-Ipnopidae 

 and Neoscopelidae-Myctophidae. Sulak (1977) lumped the 

 Ipnopidae and Bathypteroidae into the Chlorophthalmidae and 

 the Harpadontidae and Bathysauridae into the Synodontidae, 

 considering both groups arose from the Aulopidae; he did not 

 consider the position of the Myctophidae. Schwarzhans (1978) 

 considered myctophids and neoscopelids most closely related 

 and distinct from Aulopiformes on the basis of otolith mor- 

 phology. 



In his excellent study of the Evermannellidae. Johnson ( 1 982) 

 presented a rigorous analysis of 5 1 characters involving mostly 

 adult but some larval features. He concluded that neoscopelids 

 and myctophids are most closely related to each other, sharing 

 eight derived character slates, but that they were the sister group 

 of four families (Notosudidae, Scopelarchidae, Chlorophthal- 

 midae and Ipnopidae) constituting a chlorophthalmoid group 

 within the Myctophiformes. However, he noted only a single 

 shared derived character in those six families, and it is shared 

 with part of another line. Johnson (1982:95) placed the Aulo- 

 pidae in a second line and all remaining families in the third 



