NATURAL HISTORY OF A SUBSOCIAL 
TORTOISE BEETLE, AC ROM IS SPARS A BOHEMAN 
(CHRYSOMELIDAE, CASSIDINAE) IN PANAMA 
By Donald M. Windsor 
Smithsonian Tropical Research Institute, Apartado 2072, 
Balboa, Republica de Panama 
Introduction 
Insects are said to be “subsocial” if either or both parents directly 
involve themselves in the care of their own offspring after hatching 
(Michener 1969, Eickwort 1981). The literature suggests that paren- 
tal care occurs in a few neotropical chrysomelid beetles. Surpris- 
ingly, there have been few reports on the natural history of these 
species. Below I describe aspects of the behavior, ecology, and mor- 
phology of Acromis sparsa Boheman, a “tortoise-beetle” common 
throughout the Republic of Panama. 
The life histories of subsocial insects are known to differ greatly. 
In some species parents provision offspring with food, while in oth- 
ers parents buffer offspring against extremes of the physical envi- 
ronment or shield offspring from predators and parasites (Wilson 
1971, pp 121-135; Eberhard 1975). Females are the providing sex in 
most subsocial insects. 
Parental care has been reported in only nine of several hundred 
families of coleopterous insects (Hinton 1944). The trophic habits of 
these groups are diverse, embracing the eating of flesh (Tenebrioni- 
dae, Hydrophilidae), carrion (Silphidae), dung (Staphylinidae, Sca- 
rabeidae), decomposing wood (Passalidae), fungi (Scolytidae and 
Platypodidae) and green leaves (Chrysomelidae). Of the three chry- 
somelid species listed by Hinton (1944) as displaying subsocial hab- 
its, all are members of the subfamily, Cassidinae. 
The Cassidinae (“tortoise beetles” or “gold bugs”) is a large sub- 
family comprised of more than 3,000 species distributed world-wide 
and reaching greatest diversity in tropical latitudes (Arnett 1968, p. 
941). Larvae of many species are slow-moving, leaf-feeders whose 
1) Corresponding address: STRI, APO, MIAMI 34002-0011. 
Manuscript received by the editor February 26, 1987. 
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