Ecological Life History of Ptilostomis postica (Walker) 
(Trichoptera: Phryganeidae) in 
Greenbottom Swamp, Cabell 
County, West Virginia 
Mary Beth Roush and Donald C. Tarter 
Department of Biological Sciences, 
Marshall University, Huntington, West Virginia 25701 
ABSTRACT. — The ecological life history of Ptilostomis postica 
(Walker) from Greenbottom Swamp, Cabell County, West Virginia was 
investigated from December 1977 to December 1978. Length-frequency 
histograms indicate the life cycle is univoltine. Larvae achieved their 
greatest growth (75%), and case length showed its greatest increase 
(70.3%), from fall to winter. There was high correlation between case 
length and body length in fall (r = 0.72) and winter (r = 0.87), but low 
correlation (r = 0.37) in spring. The diet of the larvae changed from 
carnivorous in fall and winter to omnivorous in spring. Pupation began 
at the end of April and lasted approximately three weeks. Adult emer- 
gence began on 12 May, peaked on 20 May, and lasted two weeks. 
Chi-square tests for pupae and adults showed no deviation from a 1:1 
sex ratio at the 0.05 level. Adults are nocturnal and live less than one 
month. 
INTRODUCTION 
Several investigators, including Sibley (1926), Fankhauser and Reik 
(1935), Wiggins (1960a,b; 1961), Merrill (1969) and Hill et al. (1978), 
reported studies on the genus Ptilostomis. The objective of this investiga- 
tion was to study the ecological life history of the caddisfly Ptilostomis 
postica (Walker) in Greenbottom Swamp, Cabell County, West Virginia. 
Ptilostomis postica has been recorded from 14 eastern states, Washing- 
ton, D. C. and Quebec (Betten 1934; Ross 1944; O. S. Flint, Jr., pers. 
comm.). The authors collected it from Berkeley and Cabell counties. 
West Virginia. The larvae have been taken in both lentic and lotic waters, 
ranging from cool streams to lakes and temporary vernal pools (Wiggins 
1977). 
MATERIALS AND METHODS 
Greenbottom Swamp lies in the northwestern corner of Cabell County, 
West Virginia, 8050 m east of Homestead on State Route 2. The study 
area, rectangular in shape, is located 550 m from the Ohio River’s south 
edge. The swamp proper is 1450 m long and has a contiguous marsh on 
the north end which continues another 2100 m, forming about 14 ha of 
swamp forest. The mean water depth varies from 0.5 m during dry peri- 
ods to 1.2 m during wettest periods. Elevation of the area is 168 m above 
sea level. In the permanently inundated areas, the only tree which 
Brimleyana No. 5:107-1 16. July 1981. 107 
