Aptilotella simplex Luk & Marshall, 2014

Luk, Stephen P. L. & Marshall, Stephen A., 2014, A revision of the New World genus Aptilotella Duda (Sphaeroceridae: Limosininae), Zootaxa 3761 (1), pp. 1-156 : 35-36

Aptilotella simplex Luk & Marshall , sp. n.

Figures 234–244

Description. Body length 1.3 mm. Head ground color red-orange. Frons with polished interfrontal plate. Ocellar tubercle scarcely raised; ocelli absent; small medial seta present; ocellar bristle subequal to the length of frons. Orbital bristle absent; orbital setulae minute, in three pairs. Interfrontal setae in two pairs. Face, clypeus, and posterior half of gena brown; gena rugose, lower margin with several long setae. Antenna reddish-brown, pedicel darker. Scutum red-orange, shining, rugose; uniformly setose, posterior third microtrichose. Scutellum dark reddish-brown, finely microtrichose; 2.5 times as wide as long, 0.6 times width of scutum. Apical scutellar bristles long, 0.9 times as long as basal. Pleurites reddish-brown, weakly shining; laterotergite black. Legs dark reddishbrown; coxae dark brown; fore tibia and first fore tarsomere dark brown; distal tarsomeres of fore tarsus off-white; mid tibia with two anterodorsal and one preapical posterodorsal bristle. Wing rudiment black. Abdomen black, shining, finely rugose; tergites and sternites uniformly setose and microtrichose.

Male terminalia. Sternite 5 ( Fig. 237) rectangular with scattered short setae; posterior margin slightly pointed medially. Synsternite 6+7 ( Fig. 236) with medial bridge flanked by a stout prong on both sides, posteromedially with a membranous pouch clothed in minute denticles. Cercus ( Figs. 234, 235) 1.7 times as long as basal width; base swollen, broad, medially with a seta, lower margin with a long seta subequal to the length of cercus; the distal half curving, with two sensory setae. Surstylus ( Figs. 234, 235) pyramidal; posterior face with numerous long setae, interior half with a thick finger-like bristle; anterior margin with triangular medial excavation. Postgonite ( Fig. 239) 3 times as long as wide; posterior margin sinuate; descending portion half the length of postgonite, with two sensory setulae along inner margin; articulatory process for pregonite triangular; articulatory process for basiphallus broad, with two blunt teeth. Hypandrium ( Fig. 240) with medial rod apically broadly fan-shaped; posteromedial fork thick and shallow; hypandrial arms short, irregularly truncate; pregonite minute, irregularly rectangular. Aedeagus as in Figure 238. Basiphallus compressed, squared, with truncate epiphallus; anterior margin weakly arched; articulatory process for postgonite short and divergent. Ejaculatory apodeme discoid, inconspicuous. Ventrobasal sclerite divided. Lateral flanking sclerite narrowly fused ventrobasally; dorsal margin darkened, straight; distal quarter clothed in very fine spinules, dorsally with a field of suspended spinules. Ventral flanking sclerites darker; the basal article fused along ventral margin of lateral flanking sclerite, with a thin, tapered dorsal arm; the rod-shaped medial article originating ventrodistally to basal article; the paddle-shaped distal article originating above dorsal margin of medial article, distal margin with a dark, rod-shaped lobe.

Female terminalia. Epiproct ( Figs. 241, 242) rectangular, weakly sclerotized. Each half of tergite 8 ( Figs. 241–243) triangular, convex; dorsal margin curved; apex truncate; with scattered setae. Cercus twice as long as wide; with numerous preapical setae. Spermathecae ( Fig. 244) cylindrical, finely ridged; apex invaginated; ducts short, less than the diameter of a spermatheca, lightly sclerotized, bent at collar.

Etymology. The specific epithet refers to the unusually featureless sternite 5.

Type material. Holotype ♂, INBC. COSTA RICA: Guanacaste, Santa Elena Cloud Forest Reserve , 10°20’42”N, 84°47’53”W, 1650 m, cloud forest litter, 11.vi.2001, R.S. Anderson.

Paratypes. COSTA RICA: Guanacaste, same label as holotype (♀, DEBU); Puntarenas, Monteverde Biological Station , 10°18’53”N, 84°47’49”W, 1800 m, cloud forest litter, 10.vi.2001, R.S. Anderson (2♂, ♀, DEBU) .

Comments. Aptilotella simplex is distinctive in having a nearly straight posterior margin of the male sternite 5. The fore leg is boldly patterned in both sexes, and is strikingly similar to that of A. gracilis and A. gladia , the apterous limosinine Myrmolimosina andersoni Marshall and even a brachypterous Aluligera from Africa ( Richards, 1955). Field observations could yield insight into the potential behavioural functions of these remarkably convergent fore limbs.