Apodrosus griseus Anderson

Anderson, Robert S. & Zhang, Guanyang, 2017, The genus Apodrosus Marshall, 1922 in Cuba (Coleoptera, Curculionidae, Entiminae, Polydrusini), ZooKeys 679, pp. 77-105 : 89-90

Apodrosus griseus Anderson sp. n. Figures 13-15

Specimens examined.

6 males, 4 females. Holotype male (CMNC), labelled CUBA: Province Santiago de Cuba, Siboney-Jutici Ecological Reserve, 60 m, near Biological Station, 19.96158, -75.71534, 1.IV.2012, CarBio Team, forest semi-dry, broadleaf, CU-07. Paratypes. Siboney-Jutici Ecological Reserve, Estación Ecologica Siboney, 50 m, 19.961, -75.715, 6.II.2012, R. Anderson, dry thorn scrub (2 males, 2 females; CMNC). Siboney-Jutici Ecological Reserve, 19.96227, -75.71684, 100 m, beating shrubs at night, leg. F. Cala, 26.I.2012 (2 males, 1 female; ASUHIC). Siboney-Jutici Ecological Reserve, 19.96227, -75.71684, 100 m, beating shrubs at night, leg. N. Franz, 6.II.2012 (1 male, 1 female; ASUHIC).

Diagnosis.

This species is difficult to distinguish from other Cuban species especially A. franklyni and A. beckeli . This group of three species can be separated from other Cuban species by larger eyes, elytra with all intervals of equal elevation, and elytra with stria 10 interrupted above metacoxa. Males of the three species can be sepaarted on the basis of distinctive male genitalia. Females of this species can be separated from A. franklyni by the form of the elytral declivity in lateral view but are not separable from A. beckeli using external features.

Description.

Male. Body length 2.6-2.9 mm; in dorsal view 2.2-2.4 times longer than greatest width which is between first and second third of elytra; dorsal outline in lateral view quite flat. Vestiture composed of grey, greyish-white to brown scales, with very small recurved, fine brown setae. Eyes 1.3 times longer than wide, projected, separated from anterior margin of prothorax by 0.7 times greatest diameter of eye; line of anterior margin of eyes very slightly impressed; shortest distance between eyes (dorsal view) 0.3-0.4 times greatest width of pronotum; median furrow linear, narrow and shallow, extending from anterior margin of eyes but not reaching anterior margin of pronotum. Rostrum slightly longer than wide; epistoma apically with three setae situated on each side; nasal plate well defined, v-shaped, slightly tumid, not declivious. Antennal insertion apicad of midpoint of rostrum; scrobe curved downwards by 60°, directed posteriorly at end, barely reaching anterior margin of eye, separated from it by 1.5 times width of scrobe. Mandibles with 2 lateral setae. Antennae reddish brown; antennal scape extending to just slightly before posterior margin of eye; desmomere I very slightly longer than II. Pronotum cylindrical, slightly wider than long, greatest width near base; dorsal surface shallowly punctate but largely obscured by scales, each puncture with a curved, fine brown seta; posterior margin slightly bisinuate, slightly wider than anterior margin; scutellum subcircular, glabrous. Mesocoxal cavities about 3 times width of intercoxal process. Metasternum with lateral portions slightly tumid, not posteriorly produced. Elytra in dorsal view 1.7-1.8 times their greatest width; anterior margin sinuate; humeral region of elytra 1.5 times width of posterior margin of pronotum; lateral margins subparallel until second third, thereafter convergent; apex acutely rounded; in lateral view with dorsal outline quite flat; posterior declivity gradually descending; stria 9 complete, stria 10 interrupted above metacoxa, resuming at suture between ventrites 1 and 2; intervals completely covered with scales, with dark and light areas forming an irregular pattern; all intervals equally flat, humerus angled; interval 9 very slightly tumid above metacoxa; all intervals with recurved, fine brown setae. Venter with scales dense, large laterally on ventrites, smaller and less dense medially, ventrites 3 and 4 subequal in length, their combined length slightly shorter than ventrite 5; posterior margin of ventrite 5 widely rounded, apex at middle narrowly impressed. Tegmen with tegminal apodeme 0.8 times length of aedeagus; tegminal plate simple. Aedeagus in dorsal view about 6.5 times longer than its greatest width; apex rounded. Endophallus extended to apical two-thirds of aedeagal apodemes, with a narrow, scythe-like sclerite positioned near basal two-thirds of length, an elongate field of microtrichia positioned at base of aedeagus, and an apical hooked sclerite complex. Aedeagus in lateral view slightly evenly convex. Aedeagal apodemes about one-half length aedeagus.

Female. Body length 3.3-3.8 mm.

Etymology.

This species is named after the Latin adjective " griseus " meaning grey, after the predominantly grey scales of the body vestiture.

Natural history.

Adults were collected beating vegetation in dry thorn scrub.

Comments.

Externally, this species is very similar to A. beckeli and although males can be separated by details in the structure of the endophallus (see key), females cannot be separated using external features.