Stomion longulum, Van Dyke, 1953

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 : 149

STOMION LONGULUM EC VAN DYKE

Stomion longulum Van Dyke, 1953: 76 . Holotype: type 7387 in CAS (examined). Type locality: Santa Cruz (= Indefatigable) Island. Label data: 7.V. 32 M. Willow Jr., Templeton Crocker Expedition. Kaszab 1970: 188. Franz 1985: 93.

Diagnosis: Length 7–9 mm, width 3–4 mm; body elongate, 2.4¥ longer than wide, surface shiny; sides of abdomen are parallel; pronotum quadrate, 1.3–1.4¥ wider than long, with fine punctures, widest at middle, narrowed toward base; elytra marked by distinct parallel ridges; fine punctures arranged irregularly in intervals between ridges, single row of coarse punctures adjacent to ridges; dorsal tooth on right mandible present, moderately well developed.

Distribution: Widespread and common on Isabela (around Villamil, Volcan Alcedo, Cerro Azul) and Santa Cruz (CDRS, Academy Bay, Tortuga Bay).

Bionomics: The species occurs in littoral habitats, is most abundant in arid zone habitats, especially around the Darwin Research Station, and as high as the inversion zone on the summit of Cerro Azul, from sea level to 1500 m elevation. It occurs in coastal dunes, and especially under litter on ash and basalt rock substrates. Adults have been collected in every month of the year. Examined: 569 specimens.