Netwinged Beetles

Lycidae.

Net-winged beetles possibly represent one of the most ancient living models for mimetic insects. Their noxious body contents (expelled by voluntary bleeding), expansive colorful wing covers, and gregarious and sluggish habits make them ideal for this role. They are resembled in shape, color pattern, and behavior by members of more orders of insects than any other. A widespread lycid pattern is anterior, medial, and posterior dark cross bands on a yellow-orange background, such as in Calopteron (fig. 9.1 lc), which is resembled by Thelgetra (fig. 9.1 Id) and Lycoplasma (Cerambycidae), Correbia lycoides (Arctiidae, Ctenuchinae) (fig. 9.1 le), Oncopeltus fasciatus (Lygaeidae) (fig. 9.1 If), and others.

Most studies on Neotropical mimicry complexes based on the lycid model deal only with partial components (Darlington 1938, Parsons 1940); complete series of Batesian and Miillerian components may

be similar to those cited from northern Mexico (Emmel 1965, Linsley et al. 1961). The latter is called the Lycus fernandezi complex: in this series, the lycid is large (BL j9_18 mm), mainly orange-yellow, with the tips of the elytra, antennae, and legs black. It gathers on flowers for feeding and mating. Strongly resembling it in the same geographic areas are another lycid (Lycus arizonensis), a long-horned beetle (Elytro-leptus apicalis), a smoky moth (Zygaenidae, Seryda constans) and lithosiid moths (Ptycho-glene coccinea and P. phrada). In other complexes elsewhere, these insect types may be joined by other beetles, such as click beetles (Elateridae), false blister beetles (Oedemeri-dae), and soldier beetles (Cantharidae), as well as tiger and wasp moths (Arctiidae), seed bugs (Lygaeidae), sawflies and ichneu-monids (Hymenoptera), and robber flies (Diptera), all being of a similar appearance focused on a central lycid type.

The chemical basis for lycid unpalatabil-ity is not known, but the beetles contain yellow or pink body fluids similar to those in other chemically protected insects. The fluid may be exuded by the insects when mishandled; a slight amount of pressure on the body causes membranes on the ventral surface to rupture, releasing the fluid.

Adults of this family are typified by semitransparent, finely reticulate, soft elytra. They have a flattened form, and the wings are often widened (especially posteriorly). The prothorax is flat and shieldlike and the antennae often serrate.

Little is known of their biology aside from aspects of mimicry. Both adults and larvae of some species are known to be predatory, the former living under bark of dead trees. This is a diverse group with just over 700 species in Latin America.

References

Darlington, Jr., p. J. 1938. Experiments on mimicry in Cuba, with suggestions for future study. Entomol. Soc. London Trans. 87: 681-695.

Emmel, T. C. 1965. A new mimetic assemblage of lycid and cerambycid beetles in central Chiapas, Mexico. Southwest. Nat. 10: 14-16.

Linsley, E. G., T. Eisner, and A. B. Klots. 1961. Mimetic assemblages of sibling species of lycid beetles. Evolution 15: 15—29.

Parsons, C. T. 1940. Observations in Cuba on insect mimicry and warning coloration. Psyche 47: 1-7.

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