Aptilotella pennifera 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 : 29-30

Aptilotella pennifera Luk & Marshall , sp. n.

Figures 28–30 , and 175–186

Description. Habitus as in Figures 28 and 29 . Body length 1.3–1.4 mm. Head ground color dull yellow. Frons finely rugose except for shiny base of inner vertical bristle; pale areas silvery, the lateral pair attaining occiput and sharply converging behind; dark brown medial stripes each about one-fourth the width of frons, meeting along the anterior margin; dark brown orbital stripes each half the width of medial stripe, scarcely reaching ocular emargination; ocular emargination with pale silvery spot. Ocellar tubercle raised; ocelli present; ocellar bristle twofifths the length of frons. Orbital bristle present; orbital setulae minute, in three pairs. Interfrontal setae in two pairs. Face shining; lunule silvery; facial excavation with a broad silvery-white band continuing onto anterior twothirds of gena; clypeus and lower margin of gena dark brown; gena setaceous. Antenna light tan. Scutum and scutellum black with reddish-brown tinge, shining. Scutum uniformly setose. Scutellum bare; flat, twice wider than long, 0.6 times the width of scutum. Apical scutellar bristles 2.3 times as long as basal. Pleuron dark brown. Legs brown; mid and hind coxae black; tarsi light brown; mid tibia with two anterodorsal and one distal posterodorsal bristle; male mid femur ventrally with long setae. Wing pad ( Figs. 29 , 181 ) clavate in male, length subequal to width of scutellum; reduced in female to brown stub. Abdomen black, shining; tergites each with two rows of long setae, microtrichose basally except on syntergite; sternites finely microtrichose, with longer setae posteriorly.

Male terminalia. Sternite 5 ( Figs. 30 , 178 ) posteromedially emarginate, with a very dark, slender medial protuberance; the raised margins of emargination bearing thick setae, surrounded by numerous short and long setae. Synsternite 6+7 as in Figure 177 . Tab-like piece ( Figs. 30 , 178 ) a dark sclerotized process with two truncate lobes. Cercus ( Figs. 30 , 175, 176 ) 3.5 times as long as basal width; gradually compressed distally, but apex dilated and truncate; basal third with a long outer seta reaching apex; outer margin from midlength to apex bearing four widely-spaced setae. Surstylus ( Figs. 30 , 175, 176 ) rectangular, about twice as long as wide; posterior face bearing numerous long setae. Postgonite ( Fig. 180 ) curved; descending arm gradually tapering to a point, medially with one sensory seta; articulatory process for pregonite undeveloped; articulatory process for basiphallus knobbed with large anterior tooth. Hypandrium ( Fig. 182 ) with medial rod medially slightly constricted and apically rounded; posteromedial fork narrow and divergent; hypandrial arms oblong, the left arm broader and seemingly distorted; pregonite clubbed on both ends, four-fifths length of hypandrial arm. Aedeagus as in Figure 179 . Basiphallus compressed, arched; articulatory process for postgonite broad and erect; posteroventrally humped. Ventrobasal sclerite divided. Lateral flanking sclerites broadly fused ventrobasally; basal margin medially deeply excavated; dorsal margins widely spaced, meeting only in basal fifth, medially with a patch of minute spinules. Ventral flanking sclerites with a hatchet-shaped and heavily sclerotized club-shaped sclerite, crowned with dense suspended rows of minute trifid denticles; the arched medial article pointed beneath and broad, with a narrow and arching ascending arm terminating in an elliptical dilation; the broad distal article terminating in a round, folded lobe, ventrally with a rounded lobe curling inward and converging in the middle, on itself. Medial paired sclerites originating distally to the bend of the club-shaped sclerite and ascending with it, then leveling and terminating in a truncated, slightly upwardly curved apex.

Female terminalia. Epiproct inconspicuous. Each half of tergite 8 ( Figs. 183–185 ) shallowly convex, subquadrate; with a few setae near margin. Tergite 7 ( Fig. 183 ) posteromedially notched. Cercus three times as long as wide; with one long apical seta and several preapical setae. Hypoproct ( Figs. 184, 185 ) reduced to two discs, each densely microtrichose and with two setae. Spermathecae ( Fig. 186 ) simple; length of sclerotized ducts less than twice the diameter of a spermatheca.

Variation. Females tend to be darker in overall colouration, having especially dark legs with pale “knees,” ranging from reddish brown to dark brown, and even black in the hind femur. Setal insertions are pronounced in a few specimens, giving the scutum a punctured appearance.

Etymology. The species epithet is derived from the Latin penna, “feather, wing,” and Latin fero, “bear,” because of the delicate feather-shaped wing pad of the male fly.

Type material. Holotype ♂, DEBU. GUATEMALA: El Progreso, Cerro Pinalón , 15°5’2”N, 89°56’33”W, 2500 m, 21.ix.2008, oak/cloud forest, ex. sifted leaf litter, R.S. Anderson.

Paratypes. GUATEMALA: El Progreso, Cerro Pinalón , 15°4’57”N, 89°56’31”W, 2560 m, 17.ix.2008, cloud forest, ex. sifted leaf litter, M.G. Branstetter (♀, DEBU) ; same label as holotype (7♂, 4♀, DEBU) ; 15°5’3”N, 89°56’34”W, 2570 m, 21.ix.2008, cloud forest, ex. sifted leaf litter, L. Sáenz (♂, DEBU) ; 15°5’2”N, 89°56’40”W, 2560 m, 30.iv.2009, cloud forest, ex. sifted leaf litter (♀, DEBU) ; same as previous label but at 15°5’3”N, 89°56’44”W (17♂, 21♀, DEBU) ; same as previous label but at 15°5’14”N, 89°56’39”W, 2550 m (2♀, DEBU) ; 15°5’3”N, 89°55’57”W, 2715 m, 1.v.2009, cloud forest, ex. sifted leaf litter (♀, DEBU) ; same as previous label but at 15°5’4”N, 89°56’17”W, 2640 m (♂, 6♀); same as previous label but at 15°4’59”N, 89°55’20”W, 2845 m (3♂, 2♀, UVGC) ; same as previous label but at 15°5’1”N, 89°57’11”W, 2500 m, 2.v.2009 (♂, 3♀, UVGC) ; 15°5’7”N, 89°57’3”W, 2465 m, 2.v.2009, cloud forest, ex. sifted leaf litter, R.S. Anderson (♀, DEBU) ; peak, 15°4’52”N, 89°55’15”W, 2900 m, 1–5.v.2009, litter under shrubs, R.S. Anderson (♀, DEBU) ; trail to peak, 15°5’3”N, 89°55’57”W, 2700 m, 1–5.v.2009, mixed oak litter, R.S. Anderson (♂, 4♀, DEBU) ; 15°5’5”N, 89°56’6”W, 2680 m, 1–5.v.2009, cloud forest litter, R.S. Anderson (♀, DEBU) ; near Peña del Ángel , 15°5’1”N, 89°57’11”W, 2500 m, 1–5.v.2009, mixed oak litter, R.S. Anderson (♂, DEBU) ; trail to Peña del Ángel , 15°5’3”N, 89°57’0”W, 2520 m, 1–5.v.2009, mixed oak litter, R.S. Anderson (2♀, DEBU) ; Baja Verapaz, Biotopo El Quetzal , 15°12’33”N, 90°13’17”W, 1940 m, 7.v.2009, cloud forest, ex. sifted leaf litter (3♂, ♀, DEBU) ; same as previous label but at 15°12’24”N, 90°13’37”W, 2120 m, R.S. Anderson (2♂, 3♀, DEBU) ; 15°12’26”N, 90°13’45”W, 2150 m, 7.v.2009, ridge oak forest, ex. sifted leaf litter, R.S. Anderson (3♂, 3♀, DEBU) .

Comments. Aptilotella pennifera is parapatric with its sister species, A. corona , inhabiting closely situated montane cloud forests in south-central Guatemala. This sexually dimorphic species has paddle-winged males and apterous females, and is similar in external appearance to A. andersoni and A. quatuorchela . Since both sexes in these species are apterous, only female A. pennifera are likely to be misidentified, but the posteromedial notch of tergite 7 is diagnostic.

Figures

FIGURE 30. Aptilotella pennifera Luk & Marshall, sp. n., male terminalia. Abbreviations: CER = cercus, PG = postgonite, PTU = posteromedial tubercle of sternite 5, SUR = surstylus, TLP = tab-like piece of sternite 5, TSS = thickened setae of sternite 5.

FIGURES 28–29. Aptilotella pennifera Luk & Marshall, sp. n., male: 28—habitus, left lateral; 29—habitus, dorsal.

FIGURES 179–182. Aptilotella pennifera Luk & Marshall, sp. n.: 179—aedeagus with postgonites removed; 180—left postgonite; 181—hypandrium; 182—male left wing. 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 175–178. Aptilotella pennifera Luk & Marshall, sp. n.: 175—male terminalia, posterior; 176—male terminalia, left lateral; 177—male synsternite 6+7; 178—male sternite 5.

FIGURES 183–186. Aptilotella pennifera Luk & Marshall, sp. n.: 183—female terminalia, dorsal; 184—female terminalia, left lateral; 185—female terminalia, ventral; 186—spermathecae. Abbreviation: HP = hypoproct.