428 



ONTOGENY AND SYSTEMATICS OF FISHES-AHLSTROM SYMPOSIUM 



size, about 6 to 7 mm. They transform and settle from the 

 plankton at about 1 8 to 20 mm SL. Larvae are generally tadpole 

 shaped with large rounded heads tapering toward the tail. Larvae 

 possess an outer layer of loose flabby skin. 



Melanistic pigment occurs on the head, nape, gut and char- 

 acteristically on the pectoral fins. Postanal ventral midline me- 

 lanophores are absent; however, pigment is added laterally with 

 development. 



Head and preopercular spines are absent. 



Malacocottus group (Fig. 230).— This group includes Malaco- 

 cottus and Dasycottus. Size at hatching is not known. Larvae of 

 this group are similar to those of the Psychwlules group with 

 large, blunt heads tapering to the tail. An outer bubble or layer 

 of skin is present in both genera and is particularly pronounced 

 in Malacocottus. 



Pigmentation is present on the head, nape and over the entire 

 gut. Pigment occurs laterally on the anterior third of the tail in 

 Malacocottus larvae. As in the Psychrolutes group, the pectoral 

 fins are characteristically pigmented. 



Larvae develop four preopercular spines with a fifth accessory 

 spine present in Malacocottus. 



Hemitripterus group (Fig. 23 1 ). — This group includes the genera: 

 Hemiiripterus, Blepsias and Nautichthys. Hatching occurs at a 

 relatively large size, 7 to 1 3 mm NL. Newly-hatched larvae have 

 elongate, slender bodies which become deeper with develop- 

 ment. Nautichthys larvae have distinctively long, pigmented 

 pectoral fins. 



Pigmentation is relatively heavy with melanophores covering 

 the head, dorsal surface of the gut and over the lateral body 

 surface except for the caudal peduncle. Nautichthys and Hem- 

 itripterus larvae possess distinctive pigment bands extending 

 onto the dorsal and ventral finfolds that are not found in other 

 cottid larvae. 



Larvae develop four prominent preopercular spines and a 

 strong frontoparietal spiny ridge. This group is characterized by 



delayed ossification in the larval period and a unique "honey- 

 comb" pattern of ossification on the head. Hemitripterus larvae 

 develop large bony prickles, similar to the prickle-scales found 

 in agonids. 



Agonidae (Figs. 231 and 232). — hi least one early life history 

 stage of 9 of the 49 nominal species is known. Agonids hatch 

 at 5.5 to 8.0 mm NL. Development is a gradual transformation 

 to the juvenile form attained at 20 to 30 mm. 



Agonid larvae are generally long and slender with relatively 

 long guts. Extremes of form range from short stout genera such 

 as Agonomalus and Bothragomis to the extremely attenuated 

 forms such as Ocella and Aspidophoroides. Larvae have dis- 

 tinctively large, fan-shaped pectoral fins. 



Pigmentation varies in the family. Melanistic pigment may 

 be present on the head, nape, scattered over the gut and fre- 

 quently in bands on the postanal lateral surface of the body. 

 The pectoral fins are distinctively pigmented often with distal 

 bands of melanistic pigment. In some species (e.g. .-igonomalus, 

 Hypsagonus) pigmentation extends onto the dorsal and ventral 

 finfolds. 



Larvae are characterized by spiny heads with large fronto- 

 parietal spiny ridges, postocular spines, and usually four large 

 preopercular spines. Tiny rows of spines form in small larvae 

 and help distinguish agonid larvae. These rows correspond to 

 the plates (scales) of adults. 



(B.B.W.) Gulf Coast Research Laboratory, East Beach 

 Drive, Ocean Springs, Mississippi 39564; (W.A.L.) School 

 OF Natural Resources, Department of Fisheries, 

 Humboldt State University, Arcata, California 95521; 

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

 Fisheries Center, Post Ofhce Box 271. La Jolla, Cal- 

 ifornia 92038; (W.J.R.) National Marine Fisheries Ser- 

 vice, Southeast Fisheries Center, 75 Virginia Beach 

 Drive, Miami, Florida 33149. 



Cyclopteridae: Development 

 K. W. Able, D. F. Markle and M. P. Fahay 



THE scorpaeniform family Cyclopteridae is composed of two 

 subfamilies (Nelson, 1976), the Cyclopterinae (lumpfishes) 

 with 7 nominal genera and 28 species, and the Liparidinae 

 (snailfishes) with 18 nominal genera and 150+ species (Table 

 108). Some authors have considered the subfamilies as separate 

 families (Gill, 1891; Garman, 1892; Jordan and Evermann. 

 1896-1900; Regan, 1929; Burke, 1930; Matsubara, 1955; Ueno, 

 1970), while others have treated them together (Boulenger, 1910; 

 Berg, 1940; Greenwood et al.. 1966). We follow Nelson (1976) 

 without prejudice; both groups appear distinct yet are clearly 

 sister taxa. The most compelling synapomorphy is a ventral 

 sucking disk (secondarily lost in some liparidines) formed from 

 pelvic fin rays. The cyclopterid disk differs structurally from 



analogous structures in Gobiesociformes and Gobiidae (see for 

 example, Briggs, 1955; Ueno, 1970). Certain osteological (Ueno, 

 1970) and menstic differences (Table 108) between the subfam- 

 ilies are marked. The lumpfishes have two dorsal fins (the first 

 dorsal may be embedded in the skin and not externally visible 

 in some genera) with few total elements (4-8 spines and 8-12 

 rays), few anal rays (6-13) and vertebrae (23-29). The snailfishes 

 have a single dorsal fin with numerous elements (28-82), and 

 more anal rays (24-76) and vertebrae (38-86) (Table 108). 



Representatives of the Liparidinae have been collected in all 

 oceans from the Arctic to the Antarctic. They are found from 

 intertidal depths to greater than 7 km (Andriashev. 1954; 1975). 

 However, their distribution over shallow continental shelves is 



