WASHINGTON ET AL.: SCORPAENIFORMES 



421 



Platycephalidae (Fig. 22ij. — Platycephalids spawn small spher- 

 ical eggs (< 1 mm) with a single oil globule (Chang et al.. 1980; 

 Uchida et al., 1958). Larvae have been described and illustrated 

 for Platycephalus indicus (Ueno and Fujita, 1958) and for a 

 series of larvae incorporating seven unidentified species (Leis 

 and Rennis, 1983). Newly-hatched platycephalids are relatively 

 small (1.7-2. 3 mm) and slender-bodied, with unformed mouths, 

 unpigmented eyes, and large yolk sacs. By the time of yolk 

 absorption larvae have large heads and deep bodies which taper 

 toward the tail. The gut is quite long reaching % SL during 

 development. The pointed snout becomes distinctively long and 

 flattened. Pigmentation is usually present on the head, jaws, 

 ventral surface of the gut and along the postanal ventral midline. 

 Pigment may also be present on the dorsolateral surface of the 

 tail and pectoral fin. Larvae develop 4 to 9 preopercular spines. 

 Other head spines include: supraocular, supracleithral, parietal 

 and pterotic. Unlike most other scorpaeniforms, head spines 

 persist and become more pronounced in juveniles. Fin devel- 

 opment proceeds as follows: pectoral, caudal, dorsal, anal and 

 pelvic. 



Hoplichthyidae (Fig. 22ij. — The pelagic eggs of Hoplichthys 

 haswelli are described by Robertson (1975a) as small and spher- 

 ical with a smooth surface. A single oil globule is present. De- 

 scriptions of hoplichthyid larvae have not been published; how- 

 ever, based on Okiyama (in prep.) larvae are quite similar 

 to platycephalids. Preflexion larvae (3.2 mm) are elongate with 

 large heads and pointed snouts. The gut is moderately long 

 (>50% SL) and the early-developing pectoral fins are large and 

 fan-shaped. The snout becomes increasingly long and depressed 

 during development. Pigmentation is limited to the gut, distal 

 tip of the pectoral fin and a band on the ventral finfold midway 

 between the vent and notochord tip. Numerous clusters of small 

 spines develop in the supraocular, parietal and pterotic regions. 

 Seven spines form on the posterior margin of the preopercle 

 with smaller spines at their base. As in platycephalids, head 

 spines persist in juveniles. 



Dadylopteridae (Fig. 233).— The pelagic eggs are small (0.8 mm) 

 and slightly ovoid with a single oil globule. The egg surface is 

 smooth and unsculptured. Larvae hatch at about 1.8 mm and 

 undergo flexion of the notochord between 3.9-6.5 mm. Trans- 

 formation to the juvenile form occurs at about 9 mm. Larvae 

 are moderately deep-bodied with a distinctively blunt snout and 

 small mouth. The gut is long, reaching about 75% SL in post- 

 flexion larvae. Pigmentation occurs over the head, gut, along 

 the postanal ventral midline and around notochord tip. Pig- 

 mentation increases dramatically over most of the body in post- 

 flexion larvae. The distinctive head armature is quite different 

 from all known scorpaeniform larvae and is present in larvae 

 as small as 2.3 mm NL. A small supraoccipital spine is present 

 only during the larval period. The extremely long posttemporal 

 and preopercular spine extend posteriorly to the middle of the 

 anal fin in larvae by about 6.5 mm and persist in juveniles and 

 adults. 



COTTOIDEI 



Eggs 



Eggs are known from representatives of six of the nine cottoid 

 families recognized here (Table 107). Where known, most cot- 

 toids spawn demersal, adhesive eggs which often form clusters 

 found under rocks. Eggs are frequently brightly colored, e.g., 

 red, blue, green, yellow. The eggs of Anoplopoma fimbria are 

 pelagic. The Comephoridae of Lake Baikal are reported to be 

 viviparous. 



Most eggs are spherical and average 1-2 mm in diameter, 

 although eggs as large as 4 mm have been reported in the cottid 

 Hemitripterus and some of the cottocomephorids. A single large 

 oil globule, frequently accompanied by several small ones, oc- 

 curs in many species. The surface of the eggs is often covered 

 by a tough adhesive membrane, and may be smooth as in An- 

 oplopoma and Myo.xocephalns aenaeus (Fahay, 1983) or cov- 

 ered by tiny, radiating canals as in Arledius lateralis and Cli- 

 nocottus analis (Budd, 1940). 



Larvae 



At least one larval stage is known for 88 of the 329+ species 

 and for 46 of the 104 genera of cottoids. Major overviews of 

 larval cottoid taxonomy include: Richardson and Washington 

 (1980) on cottids; Kendall and Vinter (1984) on hexagrammids; 

 Taliev (1955) and Chemyayev (1971, 1975, 1978, 1981) on 

 comephorids and cottocomephorids; and, forthcoming Laroche 

 (in prep.) on agonids. 



Larval cottoids exhibit a broad diversity of form. Size at 

 hatching varies from 2 to 12 mm. Planktonic life may be quite 

 brief several weeks in many cottids, or may be extended up to 

 a year with a special pelagic juvenile stage as in the hexagram- 

 mids. 



Cottoid larvae exhibit such a diversity of form and devel- 

 opment that it is impossible to characterize a generalized "cot- 

 toid" larva. 



Hexagramrnidae (Fig. 224). — Larvae are known for 10 of the 

 1 1 species of the hexagrammid genera Hexagrammos. Pleuro- 

 grammus, and Ophiodon. Major works presenting descriptions 

 and illustrations include Kendall and Vinter (1984) and Gor- 

 bunova (1964b). Hexagrammids hatch at a relatively large size 

 (6-1 1 mm NL). Development is gradual from hatching to the 

 juvenile stage with a prolonged epipelagic prejuvenile period 

 (~ 30-50 mm SL). Larvae have elongate, slender bodies with 

 large eyes. Larval Hexagrammos and Pleurogrammus have blunt 

 heads, while Ophiodon larvae have pointed snouts and large 

 terminal mouths. 



Larvae are heavily pigmented especially dorsally. Melano- 

 phores are scattered over the head, gut and usually on the dorsal 

 and ventral midlines. The extent of postanal, ventral midline 

 and lateral pigmentation is useful in specific identification. 



Fin formation proceeds in the following sequence: caudal, 

 pectoral, second dorsal and anal, first dorsal and pelvic. Larvae 

 exhibit delayed ossification. Vertebral ossification in hexagram- 



Fig. 228. Larvae of the Myoxocephalus cottid group of Washington and Richardson (MS) (see Washington et al., this volume). (A) Onhonopias 

 triacis. 7.0 mm SL (original); (B) Enophrys bison. 7.0 mm SL (from Richardson and Washington, 1980); (C) Myo.xocephalus aenaeus, 7.0 mm 

 SL (from Lund and Marcy, 1975); (D) Myo.xocephalus polyacanlhocephalus. 12.0 mm SL (from Richardson, 1981a); (E) Radulinus asprellus, 

 10.9 mm SL (from Richardson and Washington, 1980); (F) Gymnocanthus tncuspis. 13.0 mm (from Khan, 1972). 



