Aptilotella andersoni 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 : 32

Aptilotella andersoni Luk & Marshall , sp. n.

Figures 34–36 , and 199–209

Description. Habitus as in Figures 34 and 35 . Body length 1.4–1.5 mm. Head ground color dull orange. Frons finely rugose except for shiny base of inner vertical bristle; pale areas silvery, the lateral pair converging on occiput; dark brown medial stripes each about one-fourth the width of frons, narrowing toward the anterior margin, then diffusing; dark brown orbital stripes each half the width of medial stripe; ocular emargination with pale spot. Ocellar tubercle slightly raised; ocelli present; ocellar bristle two-fifths the length of frons. Orbital bristle present; orbital setulae minute, in four pairs. Interfrontal setae in two pairs. Lunule with silvery spot; face weakly shining; facial excavation with a broad silvery-white band continuing onto anterior half of gena; clypeus dark brown; gena dull, setaceous. Antenna brown. Occiput dark brown. Scutum dark reddish-brown, shining, creased along posterolateral margin; uniformly setose, microtrichose except for area behind the crease. Scutellum black, shining, finely microtrichose; flat, twice wider than long, 0.6 times the width of scutum. Apical scutellar bristles 1.5 times as long as basal. Pleuron dark brown. Legs dark brown; trochanter yellow; fore femur apically orange; fore tibia and tarsi light brown; mid tibia with two anterodorsal and one distal posterodorsal bristle. Wing rudiment light brown. Abdomen black, shining; tergites each with two rows of long yellow setae, syntergite with three rows, basal margin densely microtrichose; sternites setose and finely microtrichose. Cercus and surstylus dull yellow.

Male terminalia. Sternite 5 ( Fig. 202 ) shallowly emarginate in posteromedial sixth, bordered by many long setae. Synsternite 6+7 ( Fig. 201 ) with arched medial bridge. Tab-like piece ( Figs. 36 , 202 ) a single U-shaped piece with a cylindrical base. Cercus ( Figs. 36 , 199, 200 ) tapering, twice as long as basal width; base clothed in setulae, bearing two long setae, the lower one reaching apex; apex truncate; distal half with three thick setae and an apical sensory seta. Surstylus ( Figs. 36 , 199, 200 ) subquadrate; ventral face shallowly concave and bearing long setae; posteriorly with protuberance bearing an apical and preapical ventral seta; anteriorly truncate and upwardly curved, bearing one long apical seta and a preapical sensory seta. Postgonite ( Fig. 204 ) curved; descending arm straight, tapering to a point, basally with three marginal sensory setae; articulatory process for pregonite triangular; articulatory process for basiphallus stalked, knobbed with blunt anterior tooth. Hypandrium ( Fig. 205 ) with medial rod medially slightly constricted and apically rounded and dilated to the right; posteromedial fork deeply cleft; hypandrial arms oblong, the left arm broader; pregonite clavate, two-thirds length of hypandrial arm. Aedeagus as in Figure 203 . Basiphallus compressed, strongly arched, flared at articulation with distiphallus; articulatory process for postgonite slender and erect. Ventrobasal sclerite divided. Lateral flanking sclerites broadly fused ventrobasally; convex; margins gradually converging. Ventral flanking sclerites darker; the spade-shaped sclerite distally compressed, fused to one another, and apically supporting a suspended crown of fine denticles; the medial article sharply pointed beneath basal article, laterally diverging, overlapping basal article and ascending; the distal article originating ventromedially to medial article, extending beyond spade-shaped sclerites, and apicoventrally hooked downward. Paired medial sclerites similar to distal article of ventral flanking sclerite and originating interiorly to it, apically pointed, dorsal margin more strongly sclerotized. An additional pair of triangular ventral sclerites present beneath ventral flanking sclerites.

Female terminalia. Epiproct ( Figs. 206, 207 ) indistinct, triangular and rounded apically; finely microtrichose. Each half of tergite 8 ( Figs. 206–208 ) weakly convex, rectangular; margin rounded, meeting at dorsal and ventral corners; setaceous near margin. Cercus three times as long as wide; with one long apical seta and several scattered setae. Hypoproct ( Figs. 207, 208 ) reduced to a pair of convergent rods; apex microtrichose and with a pair of setae. Spermathecae ( Fig. 209 ) simple; sclerotized ducts long, more than three times the diameter of a spermatheca.

Variation. Females tend to be darker than males in overall colouration. Teneral specimens have a uniformly brown body.

Etymology. This species is named in honour of Robert S. Anderson, whose leaf litter sampling provided much of the material that made this study possible.

Type material. Holotype ♂, UNAM. MEXICO: Chiapas, El Porvenir , 15°28’3”N, 92°16’42”W, 2950 m, 27.vii.2005, oak-pine-oyamel forest litter, R.S. Anderson.

Paratypes. MEXICO: Chiapas, same label as holotype (13♂, 16♀, DEBU; 3♂, 4♀, UNAM); 2 km NE, 15°28’14”N, 92°16’48”W, 2800 m, 27.vii.2005, mixed shrub and forest litter, R.S. Anderson (♂, DEBU) .

Comments. The fully dark brown body, legs and antennae of Aptilotella andersoni distinguish it as the darkest member of the A. corona species group. This species is known from coastal cloud forest some 60 km apart from its closest known relatives, A. quatuorchela and A. gloriosa .

Figures

FIGURE 36. Aptilotella andersoni Luk & Marshall, sp. n., male terminalia. Abbreviations: CER = cercus, SUR = surstylus, TLP = tab-like piece of sternite 5.

FIGURES 34–35. Aptilotella andersoni Luk & Marshall, sp. n., male: 34—habitus, left lateral; 35—habitus, dorsal.

FIGURES 199–202. Aptilotella andersoni Luk & Marshall, sp. n.: 199—male terminalia, posterior; 200—male terminalia, left lateral; 201—male synsternite 6+7; 202—male sternite 5.

FIGURES 203–205. Aptilotella andersoni Luk & Marshall, sp. n.: 203—aedeagus with postgonites removed; 204—left postgonite; 205—hypandrium. Abbreviations: BP = basiphallus, CSS = club-shaped sclerite, LFS = lateral flanking sclerite, MPS = medial paired sclerites, VBS = ventrobasal sclerite, VDA = distal article of ventral flanking sclerite, VMA = medial article of ventral flanking sclerite.

FIGURES 206–209. Aptilotella andersoni Luk & Marshall, sp. n.: 206—female terminalia, dorsal; 207—female terminalia, left lateral; 208—female terminalia, ventral; 209—spermathecae. Abbreviations: EP = epiproct, HP = hypoproct.