Ground Beetles

Carabidae, Carabinae. Spanish:

Escarabajos terrestres. Portuguese:

Besouros terestres.

This is one of the largest and most common beetle families, respresented in the Neotropics by at least 4,400 described species (Erwin et al. 1979). Carabids generally shun light and live in protected niches on the ground, beneath stones, logs, or other objects, and scurry to protection if exposed. However, some are gaudily colored, diurnal, and run about exposed on logs. Such are Lebia, whose larvae prey on the immatures of similar-appearing leaf beetles, and Eurycoleus, which enter into mimicry complexes (probably Müllerian) with fungus beetles (Priotelus) and darkling beetles (Poecilesthus) (Erwin and Erwin 1976).

A great many carabids are arboreal, some even restricted to epiphytic brome-liads high above the ground (Agra; fig. 9.1a). Cavernicolous species, well known elsewhere, are not common in the American tropics. The grass-feeding Notiobia peruviana (fig. 9.1b) is one of the most widespread, extending through the high elevation grasslands of the entire length of the Andean cordillera (Noonan 1981). The genus Selenophorus (fig. 9.Id) is also very common. In lowland tropical areas, the majority of species are restricted to very limited microhabitats (Erwin 19796).

Both larvae (fig. 9.1c) and adults are predaceous, feeding on other insects, and may be beneficial natural control agents

Figure 9.1 GROUND AND TIGER BEETLES (CARABIDAE). (a) Canopy carabid (Agra sp.). (b) Grass carabid (Notiobia peruviana), (c) Ground beetle, larva, (d) Ground beetle (Selenophorus sp.). (e) Caterpillar hunter (Calosoma altemans). (f) Tiger beetle (Cicindela sp.), larva, (g) Tiger beetle (Cicindela carthagena). (h) Tiger beetle (Megacephala sp.). (i) Tiger beetle (Odontocheila sp.). (j) Tiger beetle (Pseudoxychila bipustulata).

Figure 9.1 GROUND AND TIGER BEETLES (CARABIDAE). (a) Canopy carabid (Agra sp.). (b) Grass carabid (Notiobia peruviana), (c) Ground beetle, larva, (d) Ground beetle (Selenophorus sp.). (e) Caterpillar hunter (Calosoma altemans). (f) Tiger beetle (Cicindela sp.), larva, (g) Tiger beetle (Cicindela carthagena). (h) Tiger beetle (Megacephala sp.). (i) Tiger beetle (Odontocheila sp.). (j) Tiger beetle (Pseudoxychila bipustulata).

(Allen 1977). The genus Calosoma (fig. 9.1e) is composed of large, conspicuous beetles that prey on lepidopteran larvae ("caterpillar hunters," or tesoureiros in Brazil).

Adults are recognized by the narrow, elongate head that is always narrower than the first thoracic segment; the antenna are attached between the eyes and base of the mandibles. Most are shiny black and medium-sized (BL 5—20 mm), but Ence-ladus gigas reaches 7 centimeters.

Because they are ubiquitous, these beetles provide good material for ecological and zoogeographic study and have received considerable attention from biologists in Latin America (Erwin 1979a, 19796; Reichardt 1979). Although most have completely developed wings and fly well, flightless forms are particularly abundant on mountains and West Indian islands (Darlington 1970). Their general biology (mostly temperate forms) is covered by Thiele (1977).

The classification of Neotropical cara-bids is complex (Reichardt 1977). There are certainly hundreds of undescribed species.

References

Allen, R. T. 1977. Calosoma (Castrida) alternans granulatum Perty: A predator of cotton leaf worms in Bolivia (Coleoptera: Carabidae: Carabini). Coleop. Bull. 31: 73-76. Darlington, P. M. 1970. Carabidae on tropical islands, especially the West Indies. Biotropica 2: 7-15.

Erwin, T. L. 1979a. The American connection, past and present, as a model blending dispersal and vicariance in the study of bioge-ography. In T. L. Erwin, G. E. Ball, D. R. Whitehead, and A. L. Halpern, eds., Carabid bettles, their evolution, natural history, and classification. Proc. 1st Int. Cong. Carabi-dology. Junk, The Hague. Pp. 355—367.

Erwin, T. L. 19796. Thoughts on the evolutionary history of ground beetles: Hypotheses generated from comparative faunal analyses oflowland forest sites in temperate and tropical regions. In T. L. Erwin, G. E. Ball, D. R. Whitehead, and A. L. Halpern, eds., Carabid beetles, their evolution, natural history, and classification. Proc. 1st Int. Cong. Carabi-dology. Junk, The Hague. Pp. 539-587.

Erwin, T. L., G. E. Ball, D. R. Whitehead, and A. L. Halpern, eds. 1979. Carabid beetles, their evolution, natural history, and classification. Proc. 1st Int. Cong. Carabidology. Junk, The Hague.

Erwin. T. L., and L. J. M. Erwin. 1976. Relationships of predaceous beetles to tropical forest wood decay. Pt. II. The natural history of Neotropical Eurucoleus macularis Chevrolat (Carabidae: Lebiini) and its implications in the evolution of ectoparasitoidism. Biotropica 8: 215-224.

Noonan, G. R. 1981. South American species of the subgenus Anisolarsus (genus Notiobia Perty: Carabidae: Coleoptera). Pt. I. Taxonomy and natural history. Milwaukee Publ. Mus. Contrib. Biol. Geol. 44: 1-84.

Reichardt, H. 1977. A synopsis of the genera of Neotropical Carabidae (Insecta: Coleoptera). Quaest. Entomol. 13: 346-493.

Reichardt, H. 1979. The South American carabid fauna: Endemic tribes and tribes with African relationships. In T. L. Erwin, G. E. Ball, D. R. Whitehead, and A. L.

HaJpern, eds., Carabid beetles, their evolution, natural history, and classification. Proc. 1st Int. Cong. Carabidology. Junk, The Hague. Pp. 319-325. Thiele, H. U. 1977. Carabid beetles in their environments. Springer, Berlin.

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