Meeting Abstract

40.2  Monday, Jan. 5  Interspecific variation of pectoral fin morphology of surfperches (Embiotocidae) along Central California PERLMAN, B.M.*; FERRY-GRAHAM, L.A.; Moss Landing Marine Laboratories; Moss Landing Marine Laboratories bperlman@mlml.calstate.edu

Embiotocids are a groups of near-shore fishes that overlap considerably in their distributions. As a result, they are thought to partition themselves into relatively well-defined habitats. Here we ask if aspects of swimming ability, inferred by fin morphology, are related to the primary habitat of 19 embiotocid species, determined from a synopsis of multiple habitat use studies. All embiotocids are labriform swimmers. We measured the following variables from flat fins of preserved specimens: angle of the fin base with the long axis of the body, fin length, fin surface area, and aspect ratio of the pectoral and caudal fins(L²/SA). We conducted a PCA to investigate relationships among these variables. PC1 appeared to describe size. PC2 described an inverse relationship between pectoral fin aspect ratio and caudal fin aspect ratios. PC3 was dominated by the variable fin angle. ANOVA performed on these PCs with species as a fixed factor suggested that there were no significant size effects, but there were significant differences in fin aspect ratios and angles among species. Species tended to cluster by habitat type in a general sense. Closely related species sometimes grouped together, such as Amphistichus argenteus and A. koelzi, suggesting a possible phylogenetic basis for fin shape. However, other species, such as Embiotoca jacksoni and E. lateralis, occupied the extreme opposite ends of the PC2 continuum. Kinematic studies are presently being conducted to determine how such relationships might change given that fins are flexible and shape can change during use. Swimming performance experiments are also being used to quantify aspects of swimming ability among species.