MARLIAVE and PEDEN: LARVAE OF LIPARIS FVCENSIS AND L. CALLYODON 



Figure 1. — Larva of Liparis fucensis, 6.9 mm NL preflexion. Note the granular appearance of the epidermis, visible 

 especially in the cranial region, and the bubble shape of the expanded subdermal space. 



NL, while snout-anus length remained at 38% 

 NL. Body depth at yolk resorption was 27.6% 

 NL, and the subdermal space had become 

 prominent in the cranial area by this time. Pig- 

 ment development during yolk resorption in- 

 cluded the appearance of mandibular, ventral 

 gut, and nape melanin, as well as a row of about 

 10 melanophores on the ventral margin of the 

 fin fold. At hatching, the pectoral fin was only 

 slightly larger than the eye; whereas, by yolk 

 resorption it was L7 times as long and 2.3 times 

 higher than the eye. It remained appro .ximately 

 this relative size through the remaining larval 

 stages. 



Through preflexion, relative head size in- 

 creased largely through an increase in the bub- 

 ble of the subdermal space. This bubble spread 

 from the head region to include the nape and 

 gut region. At 4.1 mm NL, snout-anus length 

 had increased to 44% NL and body depth to 

 36% NL (Fig. 2b). The overall bubble appear- 

 ance imparted by the subdermal space (see 

 Figure 1) was evident by this stage, with the 

 posterior margin of the bubble at the anus. 

 Morphometric data on relative body depth and 

 snout-anus length indicated that the develop- 

 ment of the bubble is associated particularly 



with flexion (6-8 mm SL), the period of skeletal 

 development. Just after flexion, a step-function 

 increase in body depth and snout-anus length, 

 relative to head length and standard length, 

 marked the most rapid expansion of this bubble. 

 Nostrils were prominently separated into dorsal 

 and ventral nares by this stage. Through pre- 

 flexion, pigment remained essentially the same 

 as at the end of yolk resorption. Some pre- 

 flexion larvae had up to 22 well-spaced, ventral, 

 fin fold melanophores, and up to 24 postanal, 

 ventral, midline melanophores. Such individuals 

 also had denser mandibular melanophores, a 

 few melanophores on the maxillary tip, and a 

 few dorsal, midline melanophores posterior to 

 the nape. Toward the end of preflexion, at 5.25 

 mm NL, the relative body depth had increased 

 to 42%, and the snout-anus length, to 45%, giv- 

 ing the anterior body a nearly spherical bubble 

 shape. At this size the position of the anus had 

 become anterior to the posterior margin of the 

 bubble portion of the subdermal space by two 

 myomeres. The pelvic disk is not evident in 

 preflexion larvae. 



Late during the preflexion stage, larvae be- 

 tween 6 and 7 mm NL started forming dorsal 

 and anal fin rays. These median rays started 



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