Aptilotella solaria 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 : 36-37

Aptilotella solaria Luk & Marshall , sp. n.

Figures 245–251

Description. Body length 1.1–1.4 mm. Head ground color yellow-orange. Frons finely rugose, with yellow stripe medially and along interfrontal sutures; brown medial stripes each about one-fifth the width of frons, narrowing toward the anterior margin; brown orbital stripes each half the width of medial stripe; ocular emargination with small pale spot. Ocellar tubercle slightly raised; ocelli minute; minute medial seta present; ocellar bristle four-fifths the length of frons. Orbital bristle present; orbital setulae minute, in two pairs. Interfrontal setae in three pairs, the middle pair longest. Lunule light brown; face shining; gena rugose, with setulose lower margin. Antenna brown. Scutum orange, dark reddish-brown along margins and in posterior half, shining; uniformly setose. Scutellum black, shining, bare; flat, 2.5 times wider than long, 0.8 times width of scutum. Apical scutellar bristles 1.6 times as long as basal. Pleuron reddish-brown, weakly shining; anepisternum yellow-orange. Legs dull orange; coxae black; tibiae and basal half of mid and hind femora dark brown; mid tibia with two anterodorsal and one distal posterodorsal bristle; tibia with a ventrodistal comb. Wing rudiment, pale. Abdomen black, shining; tergites each with several rows of long setae, basal margin densely microtrichose; sternites setulose and finely microtrichose. Cercus and surstylus dull orange.

Male terminalia. Sternite 5 ( Fig. 248 ) in posteromedial three-fifths deeply emarginate halfway into the sternite, with two semicircular notches at each side, long setae along lateral margin, and marginal microtrichosity and denticles between the notches. Synsternite 6+7 ( Fig. 247 ) apparently with medial bridge incomplete on right side, posteromedially with a membrane articulating with sternite 5 and clothed in strong denticles. Cercus ( Figs. 245, 246 ) 1.7 times as long as basal width; base broad, inner margin with tubercle, lower margin with two setae margin, of which the outermost seta is about half the length of cercus; the distal two-thirds gradually tapering and curving. Surstylus ( Figs. 245, 246 ) bulbous; anteriorly truncate with numerous sensory setae; ventrally flat, densely setaceous, with a large forward-pointing tubercle bearing three stout, divergent, claw-like setae. Postgonite ( Fig. 250 ) 2.5 times as long as wide; posterior margin basally straight; descending portion tapering, with three sensory setulae preapically along inner margin; articulatory process for pregonite rounded; articulatory process for basiphallus stalked, knobbed with large blunt tooth. Hypandrium ( Fig. 251 ) with discoid base, bearing a round lobe arising nearly vertically and perpendicular to medial rod; medial rod apically truncate, slightly slanted to the right; hypandrial arms slender, abruptly bent midway; pregonite truncate, fused to medial rod. Aedeagus as in Figure 249 . Basiphallus cylindrical; anterior margin weakly arched; articulatory process for postgonite truncate and divergent. Ejaculatory apodeme discoid with four sensory pores, preapically with a short stem. Ventrobasal sclerite single. Lateral flanking sclerite divergent, fused ventrobasally; dorsal margin slightly rolled, basally produced into a triangular tooth; distal margin nearly vertical, dorsally projecting into squared apex. Ventral flanking sclerites dark; the basal article fused along ventral and distal margin of lateral flanking sclerite; the elongate medial article rising, its ventral margin curving apically to form a point with the nearly straight dorsal margin, apicodorsally bearing a cloud of suspended denticles; the distal article small, arising inside of medial article and curving upward.

Female terminalia. Not examined; retracted from view in the single female specimen.

Variation. The pleuron is extensively yellow-orange in the female specimen.

Etymology. The species epithet is the Latin solarium, “sundial,” because the discoid hypandrial base with its erect “sail” resembles a sundial.

Type material. Holotype ♂, DEBU. GUATEMALA: El Progreso, Cerro Pinalón, Peak , 15°4’52”N, 89°55’15”W, 2900 m, 1–5.v.2009, hardwood litter, R.S. Anderson.

Paratypes. GUATEMALA: same label as holotype (♀, DEBU); same label as holotype but nr. Peak , 15°4’56”N, 89°55’15”W, 2870 m (♂, DEBU) .

Comments. Aptilotella solaria and A. radians are the only Aptilotella with a twice emarginate male sternite 5, squat distiphallus, and discoid ejaculatory apodeme with four sensory pores and a slender stem. Although Aptilotella solaria lacks the bold facial stripes and scutal pruinosity of its sister species, it possesses an attractive yellow-striped frons and bright orange scutum. Its hypandrial morphology is unique in the genus. This species is sympatric with the distantly related A. pennifera .

Figures

FIGURES 245–248. Aptilotella solaria Luk & Marshall, sp. n.: 245—male terminalia, posterior; 246—male terminalia, left lateral; 247—male synsternite 6+7; 248—male sternite 5.

FIGURES 249–251. Aptilotella solaria Luk & Marshall, sp. n.: 249—aedeagus with postgonites removed; 250—left postgonite; 251—hypandrium. Abbreviations: BP = basiphallus, LFS = lateral flanking sclerite, VBA = basal article of ventral flanking sclerite, VBS = ventrobasal sclerite, VDA = distal article of ventral flanking sclerite, VMA = medial article of ventral flanking sclerite.