Aptilotella caerulea 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 : 18-19

Aptilotella caerulea Luk & Marshall , sp. n.

Figures 7, 8, and 61–74

Description. Habitus as in Figures 7 and 8. Body length 1.0– 1.2 mm. Head ( Fig. 74) ground color brown. Frons finely rugose, weakly shining; pale areas bluish-gray, the lateral pair attaining front margin of frons and sharply converging on occiput; dark brown medial stripes each about one-fourth the width of frons, tapering anteriorly; dark brown orbital stripes each narrower than medial stripe, lightening to amber anteriorly; ocular emargination with narrow pale border. Ocellar tubercle slightly raised; ocelli present; ocellar bristle two-fifths the length of frons. Orbital bristle present; orbital setulae in three pairs. Interfrontal setae in two pairs. Face weakly shining; facial excavation bordered by a pair of iridescent bluish-gray bars, each interjected at oral margin by a brown square spot; gena dull, finely rugose, with a pale pruinose stripe along anterior ocular margin. Antenna brown. Occiput dark brown. Scutum and scutellum dark brown, weakly shining, uniformly densely microtrichose. Scutum deeply creased along posterolateral margin; uniformly setose. Scutellum flat, 1.7 times wider than long, 0.6 times the width of scutum. Scutellar bristles subequal in length, approximately two-thirds the length of scutum. Pleuron black. Legs dark brown; coxae black; distal two-thirds of fore femur and tarsi light brown; fore and hind tibiae with orange medial band, the latter much darker; mid tibia with two anterodorsal and one distal posterodorsal bristle; male mid femur with a setal comb in ventrobasal third. Wing pad ( Figs. 8, 69) brown in male and similar in size to scutellum; reduced in female to a small, brown stub with several long apical setae. Abdomen black, shining, uniformly setose and microtrichose. Cercus and surstylus yellow.

Male terminalia. Sternite 5 ( Fig. 64) shallowly emarginate in posteromedial one-fourth; fringed with a membranous lining clothed in small hairs; flanked on each side with a patch of setae. Synsternite 6+7 ( Fig. 63) reduced; arm of sternite 7 very slender and apically hooked; medial bridge extremely narrow; posteromedially giving rise to a bulbous sclerite with a flared base. Anal aperture very large. Cercus ( Figs. 61, 62) approximately twice wider than long; the broad base laterally articulating with a notch in the epandrium; the slender portion bent near apex, with two long basal setae, three medial setae, and two preapical sensory setae. Surstylus ( Figs. 61, 62) saddle-shaped; posterior margin straight, setaceous; anterior margin sinuate. Postgonite ( Fig. 67) rounded; descending arm slender, half the total length and of uniform width, with two anterior and one posterobasal strong marginal sensory setae; posterior margin giving rise to a rounded projection before descending arm; articulatory processes for pregonite and basiphallus both undeveloped and rounded. Hypandrium ( Fig. 68) Y-shaped, medially with a perpendicular sail; medial rod apically truncated rightward; hypandrial arms swept back; pregonite inconspicuous. Aedeagus as in Figures 65 and 66. Basiphallus compressed, squared; posteroventrally humped; articulatory margin with distiphallus straight; anterior margin articulating with aedeagal apodeme; articulatory process for postgonite reduced. Ejaculatory apodeme sinuate, basal half broader and with two sensory pores. Ventrobasal sclerite divided. Lateral flanking sclerite broadly fused ventrobasally; dorsal margin straight, medially fused into a chisel-shaped tab; distal margin slanted. Ventral flanking sclerite rod-shaped, distally expanding outward into a triangular lobe. Dorsal triangular sclerites arising from inside the distal margin of lateral flanking sclerite, expanding outward like ventral flanking sclerites.

Female terminalia. Tergite 7 ( Fig. 70) posteromedially shallowly emarginate. Epiproct ( Figs. 70, 71) rectangular; medially microtrichose, with two lateral pre-marginal setae. Each half of tergite 8 ( Figs. 71, 72) weakly convex, rounded; with setae near margins; lower third shining. Cercus two times as long as wide; with one long apical seta and several other setae. Epiproct very indistinct. Hypoproct ( Figs. 71, 72) triangular, apically with four setae. Spermathecae ( Fig. 73) finely ridged; with conical invagination; collar ringed by several stubs; sclerotized ducts very short, less than the diameter of a spermatheca.

Variation. The iridescent bars may attain an intense cerulean blue colour, while the brown square spot varies significantly in size.

Etymology. Aptilotella caerulea is named for its vivid facial pruinosity.

Type material. Holotype ♂, DEBU. DOMINICAN REPUBLIC: Independencia, 32 km NW La Descrubierta Sabana Real , 1800 m, 26.xi.–5.xii.1991, cloud forest, carrion traps, S. and J. Peck.

Paratypes. DOMINICAN REPUBLIC: Independencia, 30 km NW La Descrubierta Sabana Real , 1646 m, 25.xi.–5.xii.1991, cloud forest, dung traps, S. and J. Peck (3♂, 9♀, DEBU) ; same label but from carrion (4♀, DEBU) ; same label as holotype (7♂, 10♀, DEBU) ; same label as holotype but dated 26.ix.1991, forest moss and litter (4♂, 4♀, DEBU) .

Comments. This species possesses orbital bristles and small ocelli, and a very simple distiphallus. The brilliant facial pruinosity is diagnostic.