Aptilotella involucris 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 : 27-28

Aptilotella involucris Luk & Marshall , sp. n.

Figures 22–24 , and 149–160

Description. Habitus as in Figures 22 and 23 . Body length 1.6–1.8 mm. Head ground color yellow-orange. Frons finely rugose. Ocellar triangle slightly raised; ocelli present; ocellar bristle two-thirds the length of frons. Orbital bristle present; orbital setulae in four pairs. Interfrontal setae in three pairs. Face weakly shining and pale in males, with a broad white band in facial excavation; shining in females; gena dull, lower margin setaceous. Antenna orange, first flagellomere brown. Scutum and scutellum black, shining, finely rugose and microtrichose. Scutum uniformly setose. Scutellum trapezoidal, 1.6 times wider than long, 0.6 times the width of scutum. Scutellar bristles subequal in length. Pleuron black. Legs yellow-orange; mid and hind coxae and tarsi dark brown; femora brown basally; mid tibia with two anterodorsal and one distal posterodorsal bristle. Male mid leg ( Figs. 22 , 160 ) modified: trochanter ventrally with a comb of strong setae; mid femur swollen in distal half, ventrally with long setae and stout setae before base; tibia with a ventrodistal comb. Wing rudiment dark brown. Abdomen black, shining, finely rugose and microtrichose; tergites each with two rows of setae, which become longer with each segment. Cercus orange, surstylus brown.

Male terminalia. Sternite 5 ( Figs. 24 , 152 ) anteromedially grooved; posteromedial third projected and raised, flanked by setae, its margin medially excavated and sunken, and giving rise to a pair of very dark, compressed, knobby processes with a large inner tooth which clasps the cercus. Synsternite 6+7 as in Figure 151 . Anal aperture dorsally deeply emarginate. Cercus ( Figs. 24 , 149, 150 ) gradually tapering, twice as long as basal width; base swollen and setulose; apex sloped inward; distal third bearing several sensory setae, three stout setae and a long seta next to the middle stout seta. Surstylus ( Figs. 149, 150 ) semi-cylindrical, twice as long as wide; posterior margin setaceous, basally tuberculate; distal third with several sensory setae. Postgonite ( Fig. 154 ) curved with strongly concave anterior margin; descending arm half the total length, gradually tapering, with two basal sensory setae; articulatory process for pregonite triangular and rounded; articulatory process for basiphallus a small knob on a broad stalk. Hypandrium ( Fig. 155 ) with straight, apically truncate medial rod; posteromedial fork rounded and divergent; rectangular hypandrial arms appearing triangular due to membranous connection with medial rod, the left arm apically dilated; pregonite clavate with thicker anterior margin. Aedeagus as in Figure 153 . Basiphallus arched, with prominent posterior hump; articulatory process for postgonite slender, directed forward. Ejaculatory apodeme round with a descending apical stalk. Ventrobasal sclerite divided. Lateral flanking sclerite darkened and dorsally emarginate in distal third; dorsal margin rolled, straight; basal margin slanted; distal margin rounded, supporting in dorsal half a membranous sac clothed in fine rows of minute denticles. Ventral flanking sclerites with the basal article fused posteroventrally and along ventrodistal margin of lateral flanking sclerite, distally tapering to a point; the medial article confluent with basal article, ascending and ending beneath membranous sac; the distal article articulating with ventrodistal margin of basal article, ladle-shaped and opening outward. Medial paired sclerites originating from inside distal margin of lateral flanking sclerites, slender portion convergent and protruding between membranous sacs. Distal oval sclerites flanking slender portion of medial paired sclerites. Ventral paired sclerites descending between ladle-shaped distal articles; apically with a leaf-shaped sclerite, flanked ventrally by a rod-shaped sclerite and ventrolaterally by triangular ventral plate-like sclerites.

Female terminalia. Epiproct ( Figs. 156, 157 ) subpentagonal, with indented basal margin; medially densely microtrichose. Each half of tergite 8 ( Figs. 156–158 ) subpentagonal, convex; apex rounded; distal half setose. Tergite 7 ( Fig. 156 ) anteromedially notched. Cercus 1.5 times as long as wide; with several preapical setae. Hypoproct ( Figs. 157, 158 ) reduced to a pair of lightly sclerotized, microtrichose discs. Spermathecae ( Fig. 159 ) simple; length of sclerotized ducts approximately twice the diameter of a spermatheca.

Etymology. The manuscript name used for this species by Smith (1994) is here retained. It is derived from the Latin involucer, “unable to fly.”

Type material. Holotype ♂, INBC. COSTA RICA: Cartago, Tapanti—Macizo de la Muerte National Park , N of La Esperanza del Guarco, 17–18.viii.2001, dung traps in cushion plants, S.A. Marshall.

Paratypes. COSTA RICA: Cartago, same label as holotype (5♀, DEBU) ; Cerro Chirripó , trail to, 2800 m, 27.vi.1999, mixed oak forest, leaf litter, R.S. Anderson (♂, DEBU) ; San José, km 74 SE San José, 25.ii.1984, dung trap, H. Howden (4♂, 4♀, DEBU) ; same label as previous but from flight intercept trap (♀, DEBU) ; Pan-American Highway , km 95, 3200 m, 13.iv.1985, oak cloud forest, L. Masner (♀, DEBU) ; km 68, Tres de Junio Bog , 2600 m, 10.ii.1996, litter ex forest adjacent to sphagnum bog, R.S. Anderson (♂, DEBU) ; km 87, near Cerro Buenavista , 9°36’30”N, 83°46’W, 3150 m, 8.vi.1997, mixed elfin forest litter, R.S. Anderson (♂, ♀, DEBU) ; km 71, near Tres de Junio , 23.vi.1999, wet cloud forest leaf litter, R.S. Anderson (2♂, ♀, DEBU) ; km 78, near Ojo de Agua , 8.vii.1999, cloud forest leaf litter, R.S. Anderson (♀, DEBU) ; Cerro de la Muerte , 3200 m, 3.iv.1985, cloud forest, pan traps, L. Masner (♀, DEBU) ; Cerro de la Muerte , 7–13.iv.1985, oak cloud forest, L. Masner and H. Goulet (♂, DEBU) ; Heredia Porrosati, 6 km N San José de la Montaña , 10°5’30”N, 84°7’W, 1900 m, 21.vi.1997, montane forest litter, R.S. Anderson (♀, DEBU).

Comments. Aptilotella involucris is a highly apomorphic and sexually dimorphic species that is readily recognized by its large and slender form. The distiphallus is arrayed with internal and ventral sclerites of uncertain affinities. Females possess a strongly domed tergite 7 which may be mistaken for an epandrium, but examination of the unmodified mid leg and non-pruinose face eliminates confusion as to the sex of the individual.

Figures

FIGURE 24. Aptilotella involucris Luk & Marshall, sp. n., male terminalia. Abbreviations: CER = cercus, CLP = clasper-like process of sternite 5, SUR = surstylus.

FIGURES 22–23. Aptilotella involucris Luk & Marshall, sp. n., male: 22—habitus, left lateral; 23—habitus, dorsal.

FIGURES 156–160. Aptilotella involucris Luk & Marshall, sp. n.: 156—female terminalia, dorsal; 157—female terminalia, left lateral; 158—female terminalia, ventral; 159—spermathecae; 160—male mid trochanter, femur and tibia, anterior. Abbreviations: EP = epiproct, HP = hypoproct.

FIGURES 149–152. Aptilotella involucris Luk & Marshall, sp. n.: 149—male terminalia, posterior; 150—male terminalia, left lateral; 151—male synsternite 6+7; 152—male sternite 5.

FIGURES 153–155. Aptilotella involucris Luk & Marshall, sp. n.: 153—aedeagus with postgonites removed; 154—left postgonite; 155—hypandrium. Abbreviations: BP = basiphallus, LFS = lateral flanking sclerite, LLS = leaf-like sclerite of ventral paired sclerites, MPS = medial paired sclerites, MS = membranous sac, VBA = basal article of ventral flanking sclerite, VBS = ventrobasal sclerite, VDA = distal article of ventral flanking sclerite, VMA = medial article of ventral flanking sclerite, VPS = ventral paired sclerite, VRS = ventral rod-like sclerite.