Ditty and Shaw: Larval development and distribution of Lobotes surinamensis 



37 



posttemporal and supraclei- 

 thrum by 4.5 mm; a low, simple 

 ridge occurred along the 

 pterotic at about 5.0 mm (Fig. 

 1). The posttemporal and 

 supracleithral spines were par- 

 tially covered by epithelium 

 but both they and the pterotic 

 ridge were visible on the larg- 

 est specimen examined. 



Tripletail larvae developed 

 two series of preopercular 

 spines, one along the outer 

 shelf and the other along the 

 inner shelf. Both outer and in- 

 ner shelves have dorsal and 

 ventral limbs. Three spines oc- 

 curred along the posterior mar- 

 gin of the outer shelf of 2.2-2.4 

 mm larvae, the longest at its 

 angle (Fig. 1). A fourth spine 

 was forming but was small at 

 2.2 mm. Fifth and sixth spines 

 were added by 6.0 mm; a sev- 

 enth spine, by 7.0 mm. One to 

 two small additional spines 

 were added as larvae grew. By 

 15.5 mm, three to five spines 

 were visible along the dorsal 

 margin of the outer preopercular 

 shelf, one at the angle, and usu- 

 ally three along the ventral 

 margin; the anterior-most 

 spine along the ventral margin 

 was short and blunt (Fig. 1). All 

 spines along the outer shelf 

 were present in the largest 

 specimen examined (i.e., 26.0 

 mm). Along the inner preop- 

 ercular shelf, one spine was 

 present in 2.2-2.4 mm larvae 

 and three to four spines by 5.0 

 mm (Fig. 1). Spines along the 

 inner shelf were short and 

 blunt and covered by epithe- 

 lium. A spine occurred along 

 the posterior margin of the 

 subopercle by 6.0-6.5 mm, near 

 but dorsal to the angle spine of 

 the outer preopercular shelf. The 

 subopercular spine was resorbed 

 by 20.0 mm. A small, flexible spine was present dor- 

 sally on the opercle by 10.0 mm. This spine was diffi- 

 cult to locate on unstained larvae because it was cov- 

 ered by integument. 



A continuous median finfold extended posteriorly 

 around the body from the nape to the anus of early 

 larvae. Pelvic fins were precocious and elongate 

 (usually >25% SL) and had a full complement of 



