Liothorax alternatus Horn 1870, new combination

Liothorax alternatus (Horn, 1870), new combination

(Figs. 1–7)

Aphodius alternatus: Horn 1870: 129, Horn 1887: 22, Gordon 1977: 164 (lectotype designation) Aphodius (Volinus) alternatus: Schmidt 1913: 143, Schmidt 1922: 176; Hatch 1971: 454 Aphodius inermis: Robinson 1940: 147, Gordon 1977: 164 (as a synonym of A. alternatus), Dellacasa 1988: 236 Aphodius (Calamosternus) moclipsi: Hatch 1971: 457, Gordon 1977: 164 (as a synonym of A. alternatus), Dellacasa

1988: 335

Aphodius (Chilothorax) alternatus: Dellacasa 1988: 85

Type locality: California, U.S.A. (for Liothorax alternatus).

Type depository: Museum of Comparative Zoology, Harvard University, Cambridge, MA, U.S.A. (for Liothorax alternatus).

Redescription: Length 4.0–6.0 mm; body moderately elongate, convex, shiny, glabrous. Color black; clypeal margin red; pronotum with weak red coloration laterally, elytra with interstriae alternating yellow and black; legs reddish brown; antennal club piceous (Fig. 7); some individuals have black elytra with second interstria, basal and apical margins dark yellow (Fig. 6); some individuals have entirely black elytra (Fig. 5). Head anteriomedially moderately convex, with sparse, coarse, evenly spaced punctures; punctation more irregular, coarser distally. Clypeus weakly sinuate medially, widely rounded laterally, distinctly bordered; border weakly upturned; genae obtusely rounded with short setae, protruding beyond eyes; front with coarse, evenly spaced punctures. Pronotum moderately transverse with evenly spaced, moderately dense punctures; punctation denser laterally; lateral margins weakly arcuate with thin border; hind angles obtusely rounded; base arcuate with fine border, sometimes border obsolete medially. Scutellum weakly excavate, smooth, with fine punctures on basal half. Elytra almost parallel-sided; striae well defined with distinct punctures, subcrenulate; interstriae flat with irregular, distinct punctures. Hind tibiae with superior apical spur slightly longer than first tarsomere; first tarsomere longer than following two combined. Male fore tibiae with apical spur broad, evenly curved inward at apex; head and pronotum more transverse with less coarse, less dense punctures than in female. Female fore tibiae with apical spur evenly acuminate apically.

Distribution: Canada (British Columbia to Manitoba); U.S.A. (Washington to southern California, east to Michigan). In HAHC there is a specimen from Tacubaya (Mexico: Distrito Federal), 7.II.1974, Col. B. Kohlmann, ex coll. Martínez, “anegado alberca” [drowned in a cistern]. However, the identification of this specimen is doubtful because of it is a female and the pronotum has irregular, dual punctures instead of even punctures. Before we can state that this taxon occurs in Mexico, this collecting record needs to be confirmed with addition specimens.

Bionomy: This is a winter and early summer species, which is usually taken near margins of ponds and streams. Specimens can be found around prairie sloughs and lakes either up on bordering vegetation or crawling on the ground (Gordon, personal observation). Larvae are sometimes found in golf turf (Hatch 1971) and are also observed on the surface of vernal pools and climbing on the stems of plants growing in the water (Rogers 1997). Massive congregations of this species are sometimes observed in flight.