137 
Appalachian Trechus of the vandykei Group 
productive microhabitat proved to be damp, but not excessively wet, 
litter in Rhododendron thickets. Beetles were transported to the laboratory 
in 4-ounce glass or plastic jars cooled in an ice chest. During the 
summer of 1982, specimens were maintained alive in a refrigerator at 
the Highlands Biological Station prior to electrophoresis, which was 
also conducted at the Station. Beetles collected at the end of the 
summer in 1982 and all 1983 and 1984 collections were returned alive to 
the University of Cincinnati; after identification and sexing they were 
placed individually into 400-jul microcentrifuge tubes and frozen at 
-80° C until used for electrophoresis. 
Electrophoresis was conducted on vertical polyacrylamide slab gels 
with a Hoefer Scientific SE600 system. Single beetles were ground in 
approximately 40^1 of grinding buffer (0.01M Tris-HCl, pH 7.0, 
containing 0.001M EDTA, 1% Triton-X, and 25% sucrose). Initial 
screening dictated that only a single sample could be obtained from 
each specimen because of the beetles’ small size, low enzyme activity, or 
both. Ten enzymatic systems were surveyed: alkaline phosphatase (ALP), 
carbonic anhydrase (CAH), esterase (EST), hexokinase (HEX), malate 
dehydrogenase (MDH), mannose phosphate isomerase (MPI), phospho- 
glucose isomerase (PGI), phosphoglucomutase (PGM), superoxide 
dismutase (SOD), and xanthine dehydrogenase (XDH). Only five systems, 
to include eight presumptive loci, could be consistently scored in all 
individuals of all taxa: CAH (1 locus), EST (2 loci), MDH (2 loci), PGI 
(1 locus), and SOD (2 loci). Staining techniques for these systems were 
adapted from Brewer (1970), Harris and Hopkinson (1976), and Shaw 
and Prasad (1970). 
All data analysis was accomplished with a FORTRAN-77 version 
of the BIOSYS-1 Program developed by Swofford and Selander (1981). 
This program contains routines for population genetic analysis as well 
as procedures for the production of phenograms and other types of 
phylogenetic analyses. 
RESULTS 
For practical purposes, the 19 populations sampled were assigned 
to the five subgroups whose limits and distribution are described in the 
introductory section. Locations of the sampling sites and the abbreviations 
employed for them throughout this paper are presented in Table 1, and 
their relative geographic configuration is shown in Fig. 1. The sampled 
vandykei group populations (except those of Sandymush Bald and 
Cheoah Bald) coexist with larger Trechus species of other groups; see 
Barr (1985a) for details of the various species guilds to which the 
vandykei-g roup isolates belong. 
