Acrotrichis difficilis, Darby, Michael, 2014

Darby, Michael, 2014, Studies of Madagascan Ptiliidae (Coleoptera) 3: The genus Acrotrichis including twenty seven new species, Zootaxa 3866 (2), pp. 151-201 : 171-172

Acrotrichis difficilis sp. n.

( Figs. 13A –J)

Habitus Fig. 13A . Length 0.74 mm. Colour yellow, antennae and legs paler yellow. Antennomeres 3–11 0.30 mm long Fig. 13 C. Width across eyes 0.25 mm. Mentum and submentum chaetotaxy Fig. 13 J. Pronotum 0.36 mm wide, 0.20 mm long, sides evenly curved to hind angles without a sinuation Fig. 13 B. Elytra 0.48 mm long, 0.50 mm wide. Posterior border of mesoventral collar evenly rounded without a medial excision Fig. 13 G (note: the small medial excision in the figure is the result of damage). Posterior border of metaventrum and metacoxal plates Fig. 13 H.

Male: ventrite six with 6/7 spines Fig. 13 F; aedeagus Fig. 13 E.

Female: spermatheca Fig. 13 D.

Etymology. The epithet refers to the difficulty of separating this species from other small pale species particularly when they are teneral examples of darker species.

Remarks. The yellow colouration and length of the elytra together with the form of the genitalia should distinguish this species.

Type data. Holotype: ♀, Ranomafana N.P., sifting, S.21˚15’ E.47˚25’, 970–990 m, 13–15.xi.2010, P. Banar ( BMNH). Paratypes: 2♀ 3♂ same data as holotype; 3 examples, Ranomafana N.P., by stream close to main entrance, sifting, 17.xi.2010, P. Banar ( BMNH).

Figures

FIGURE 13. A. difficilis. A, habitus; B, side of pronotum viewed at 45 ˚; C, antennomeres 3 – 11; D, spermatheca; E, aedeagus; F, ventrite six; G, mesoventral collar and lateral margin x 760; H, metaventral posterior margin and metacoxal plates x 760; I, elytron; J, mentum and submentum showing chaetotaxy.