Tachyta (Paratachyta) acuticollis (Putzeys 1875)

Tachyta acuticollis (Putzeys)

Tachys acuticollis Putzeys, 1875:740 [holotype, sex unknown, in GCM, not seen by me; type-locality: Wokan, Aru Islands].—Andrewes, 1925:166.

DIAGNOSIS.—The reflexed pronotal margins, four spotted elytra, and lack of microsculpture are distinctive in the genus.

DESCRIPTION.—Form (Figure 3): Short and robust, dorsum convex. Pronotum quadrately cordiform; elytra parallel-sided to apical third then convergently rounded, generally shorter, and broader than members of T. coracina.

Color: Shiny piceous dorsally, more rufous ventrally. Each elytron with one basal and one apical white spot. Appendages testaceous, except femora infuscated.

Head (Figure 17): Slightly broader and shorter than in T. coracina members, with more deeply impressed and abruptly convergent frontal furrows; eyes large and prominent; mouthparts (Figure 16).

Pronotum (Figure 18): Quadrately cordiform, sides slightly sinuate basally, hind angles acute; basal transverse impression deeply engraved, sinuate, and broadly interrupted at middle; disc highly convex to lateral ridge, sides broadly reflexed much as in members of the New World Tachymenis.

Elytra (Figure 19): As in T. coracina members.

Microsculpture: Absent from dorsal surface, except labrum.

Genitalia (Figure 7): Median lobe shorter and less bent ventrad than in T. coracina males; two apical structures more rounded and C-shaped sclerite less developed. Female stylus as in Figure 13.

Size: Length, 1.80 to 2.30 mm; width, 0.84 to 1.08 mm, 8 specimens measured.

NATURAL HISTORY.—According to Darlington (1962), “This species probably occurs at low altitudes throughout New Guinea, on the bark of fallen trees and logs in rainforest. …” I have seen specimens collected in January, March, April, May, July, August, September, October, and December; some of those collected in March to July and in August were teneral. No specimen has been recorded above 500 m elevation.

DISTRIBUTION (Figure 29).—The range of this species extends from the Philippines south to New Guinea and Aru Island, east to New Ireland, and west to the Moluccas (in part from Darlington, 1962). As Darlington (1962) points out, this species is complementary in distribution to T. coracina although some overlap occurs.