Meeting Abstract

P1.24  Sunday, Jan. 4  Distinguishing the validity of subspecies of the endangered Hawaiian tree snail Achatinella mustelina using a principal component analysis of shell characters PELEP, Peltin O.*; HADFIELD, Michael G.; University of Hawaii at Manoa; University of Hawaii at Manoa peltin@hawaii.edu

The endangered Hawaiian tree snail species Achatinella mustelina was divided into 25 subspecies based on traditional shell characters (Welch 1938). A recent molecular genetic analysis of 21 populations through the species range yielded no support for the subspecies distinctions. In the present study 11 shell characters were measured on photos of 50 shells of each of 19 nominal subspecies using image-analysis software; the shells are in the collections of the B. P. Bishop Museum, Honolulu. The characters included both traditional linear measurements (5), plus perimeter (3) and surface-area (3) measurements. The resultant data were subjected to principal component analyses to determine the most important discriminating characters and to answer the question, do the shell characters support assignment to the nominal subspecies? The principal components (PCs) explained 95.5% of the variance among measurements, and two, PC1 and PC2, provided most of the information. Pair-wise comparisons of the subspecies, based on PC1 and PC2, plus examination of the subspecies ranges on a map, provided support for 11 of the subspecies (i.e., they were distinct from all subspecies with overlapping ranges), but not for the remaining 8 (i.e., they were not distinguished from sympatric subspecies). It remains for these results to be resolved with the results of molecular genetic analyses of snails from the same populations.