Stomion genovesa, 2004

Finston, Terrie L. & Peck, Stewart B., 2004, Speciation in Darwin’s darklings: taxonomy and evolution of Stomion beetles in the Galápagos Islands, Ecuador (Insecta: Coleoptera: Tenebrionidae), Zoological Journal of the Linnean Society 141 (1), pp. 135-152 : 150

STOMION GENOVESA FINSTON & PECK , SP. NOV.

Stomion helopoides Waterhouse. Van Dyke, 1953: 74 (from Genovesa Island, a misidentification).

Holotype: In CMN collection. Type data: Galápagos Islands, Genovesa Island. Holotype data: Darwin Bay, 26–28.III.92, J. Cook and S. B. Peck, under Cryptocarpus and Bursera litter, 92-68. Paratypes: 99 with same data, and 200 with: Genovesa Island, Prince Phillips Steps, 27.III.92, arid zone, 20 m, Cook and Peck, 92-61.

Etymology: The name is a noun used in apposition, and is the name of the island to which the species is restricted.

Diagnosis: Length 8–10 mm, width 4–5 mm; body broad, convex, 2.0¥ longer than wide; striae and intervals of elytra nearly the same height, giving this species an overall smooth surface; pronotum transverse, 1.5¥ wider than long, coarsely, shallowly punctured, widest behind middle, slightly constricted at base; elytral punctures coarse along striae, smaller in intervals; right mandible with well-developed dorsal tooth as in Figure 13 . The etymology of the name comes from the distribution of this species, which is restricted to Genovesa Island.

Distribution. Genovesa Island: Darwin Bay and Prince Philip’s Steps.

Bionomics. Found in the arid zone, under rocks and in litter of Cryptocarpus shrubs and Bursera trees. Abundant in nesting areas of red-footed boobies. Adults collected from February to June and November. Examined: 341 specimens.

Figures

Figures 12–17. Scanning electron micrographs of the head and pronotum (18¥) with inset of pronotal disc (300¥) and the elytral disc (100¥). Figs 12, 13. S. longicornis; Figs 14, 15. S. helopoides; Figs 16, 17. S. galapagoensis.