554 



ONTOGENY AND SYSTEMATICS OF FISHES-AHLSTROM SYMPOSIUM 



0.50 X 1. 30 mm, contain no droplets, and have an unsculptured 

 chorion with a cap-Uke structure at one end. Incubation time 

 is not known. 



Larvae 



Morphology. — Larval size and degree of development at hatch- 

 ing are unknown. However, 5. pietschmanm at 1 .9 mm NL has 

 a rather large yolk sac (containing an apparently segmented yolk) 

 in addition to pigmented eyes and an open, presumably func- 

 tional, mouth. Notochord flexion occurs after 2.7 mm but before 

 3.5 mm NL in 5. pietschmanni, and before 4.3 mm in S. prae- 

 matura. Development to the essentially larval mature form is 

 gradual. The juvenile stage may be taken to begin with com- 

 pletion of the dorsal and anal fins and the acquisition of the 

 principal caudal rays (ca. 4-5 mm), and the adult stage to begin 

 when the male genital papilla or the ovaries of the female be- 

 come discemable (longer than ca. 9 mm SL). The distinctive 

 schindleriid terminal section at the rear of the vertebral column 

 does not become apparent until the late larval or early juvenile 

 period. 



Aside from fin development, morphology changes little during 

 larval development. The swim bladder moves posteriorly from 

 myomeres 6-8 to myomeres 14-1 5 in 5. pietschmanni; a similar 

 migration presumably occurs in S. praematura (e.g., Sardou, 

 1974). Preanal length is greater in S. praematura than in S. 

 pietschmanm. 



Pigmentation. — Sdn'mdXmids are lightly pigmented throughout 

 development (e.g.. Miller etal., 1979; Ozawa and Matsui, 1979). 

 During the larval and early juvenile period, S. pietschmanm 

 has one to four pairs of melanophores along the sides of the gut 

 (usually two or three pairs), one to four melanophores along the 

 ventral midline of the tail (usually two or three), and pigment 

 on the posterior dorsal surface of the swim bladder. The pos- 

 terior tail melanophore is typically more elongate than the others 

 (Fig. 298). All but the swim bladder pigment is lost during the 



juvenile stage. Larval pigmentation of 5. praematura. as shown 

 by Ozawa and Matsui (1979), and juvenile pigment, shown by 

 Sardou (1974), are very similar to that of 5. pietschmanni. Like 

 S. pietschmanni, S. praematura retains only the posterior swim 

 bladder pigment in the adult stage (Fig. 298). 



A/m5/(C5. — Meristics for Schindleria are: Vertebrae 15-25 -I- 

 12-21 = 33-44; D 15-22; A 10-14; P 15-17; and C 13prin. A 

 combination of caudal vertebrae and anal fin ray counts usually 

 will distinguish the two species. 



The caudal fin rays are the first to develop, followed by the 

 dorsal and anal fin rays (forming simultaneously). Pectoral fin 

 rays are the last to ossify. Pelvic fins never form. 



Relationships 



Early life history characters, to the extent that they are pres- 

 ently known, do little to clarify the phylogenetic position of the 

 Schindlerioidei. For example, Gosline ( 1 963b, 1971) speculated 

 that Schindlerioidei might be derived from an ammodytoid 

 ancestor; however, while both suborders share some characters 

 (e.g., an elongate larval form with preanal length just over 50% 

 body length), they differ in other important ways (e.g., late de- 

 velopment of pectoral fin rays in schlindleriids and early de- 

 velopment in ammodytoids). Knowledge of spawning and early 

 development might aid in ascertaining schindleriid relationships 

 although at present this group seems destined to remain an 

 enigma. 



(W.W.) Marine Ecological Consultants, 531 Encinitas 

 Boulevard, Suite 1 10, Encinitas, California 92024; (E. 

 G.S.) National Marine Fisheries Service, Southwest 

 Fisheries Center, PO Box 271, La Jolla, California 

 92038; (A. CM.) National Marine Fisheries Service, 

 Northwest and Alaska Fisheries Center, 2725 

 Montlake Boulevard East, Seattle, Washington 98 112. 



Trachinoidea: Development and Relationships 

 W. Watson, A. C. Matarese and E. G. Stevens 



THE blennioid infraorder Trachinoidea, as used here, con- 

 tains about 140 species in 1 1 families of morphologically 

 quite diverse, but generally small, primarily shallow-living tem- 

 perate and tropical marine demersal or burrowing fishes (Chias- 

 modontidae is bathypelagic; Cheimarrhichthyidae inhabits fresh 

 water). These families have not always been considered as closely 

 related (e.g., Gosline, 1968, 1971), but we follow Nelson (1976) 

 in considering them together here. Nelson ( 1 976) originally placed 

 16 families in the Trachinoidea, but subsequently synonymized 

 the Limnichthyidae with Creediidae (Nelson. 1978). Springer 

 (1978) removed Oxudercidae to the Gobiidae. Three other fam- 

 ilies are treated elsewhere in this volume; Bathymasteridae and 

 Dactyloscopidae with the Blennioidea (Matarese et al., this vol- 

 ume) and Opistognathidae with the Percoidei (G. D. Johnson). 

 In this brief review, we summarize the present state of knowl- 



edge of the early life histories of trachinoid fishes and attempt 

 to determine whether such information contributes to our un- 

 derstanding of their phylogenetic relationships. Unfortunately, 

 early life histories, mostly incomplete, are known for only a 

 small number of species (Table 134). This paucity of early life 

 history data makes generalizations about development tenuous 

 at best, but for purposes of this paper the known taxa are con- 

 sidered representative. 



Development 

 Eggs 



Eggs are unknown for the Percophididae, Trichonotidae, and 

 Leptoscopidae. Only ovarian eggs have been described for the 



