Bromeloecia fractacincta Yau and Marshall, 2018

Yau, Tiffany & Marshall, Stephen A., 2018, A revision of the genus Bromeloecia Spuler (Diptera: Sphaeroceridae: Limosininae), Zootaxa 4445 (1), pp. 1-115 : 37-41

Bromeloecia fractacincta Yau and Marshall sp. n.

(Figs. 7.1–7.14)

Description: Body length 1.2–1.6 mm (males), 1.0– 1.7 mm (females). Generally similar to B. abundantia .

Head: Length of anterior fronto-orbital seta 0.5x posterior seta.

Wing: Costa ending at 4/5 of wing length. Angle between costa and R4+5 75°. Distance between radial fork and r-m 5x length of r-m; dm-cu 1.8x length of r-m and distance between crossveins 1.5x length of dm-cu.

WIPs: Basal angle of distal spot wide, 95°.

Legs: Ventral surface of male mid tibia with a comb of 9 stout setae increasing in size distally, followed by a large apical seta on distal half; ventral surface of female mid tibia with only large apical seta.

Male abdomen and terminalia: S5 with posteromedial extension shielding a pair of dorsal, smooth, apically rounded lobes and a pair of wedge-shaped sclerites on either side of extension; 1 tight row of setae anterior to posteromedial extension, above second and third setae, with 1 strong seta on each side. Anteroventral arm of synsternite 6+7 of uniform length, with paddle-like apex peripherally desclerotized. Anteroventral process on right side of epandrium long, surpassing hypandrium, forming a complete bridge with left thin long sclerite (probably homologous with left anteroventral process) and fragments; all articulating with anterior hypandrial apodeme and hypandrial arms. Cercus thin, apically tapering. Surstylus quadrate.

Basal half of hypandrial arms broad, distal half slender. Distiphallus LFS triangular, apically with finger-like stub; FDS laterally with long, slender lobe, medially forming a posteriorly bent tongue; SDS broad, D-shaped, distally desclerotized to almost membranous.

Female abdomen and terminalia: S7 posteromedially notched; posteriorly with 1 row of setae of alternating size on each half and anteriorly with a pair of small setae. Each half of T8 large, triangular, with 1 seta. S8 bandlike, of uniform length; with medial hook and spicule on each side. Cercus slender, with stout hooked apical seta. Each spermatheca with 1 short hemispherical pit and 1 long thimble-shaped pit.

Type specimens: Holotype: ♂: GUYANA: Potaro-Siparuni: Mount Wokomung , 05°6ʹ35ʺN, 059°49ʹ15ʺW, 1° rainforest, 1234 m, human dung pitfall trap, 27 Oct–1 Nov 2004, B. Hubley ( ROME).

Paratypes: ECUADOR: Pichincha: Rio Palenque , carrion, 27 Feb 1979, S. A. Marshall (1♂, DEBU) . GUYANA: Potaro-Siparuni: Mount Wokomung , 05°7ʹ53ʺN, 059°48ʹ31ʺW, 1° rainforest, 698 m, human dung

pitfall trap, 21–26 Oct 2004, B. Hubley (3♀, ROME, DEBU); same as holotype (2♂, 6♀, ROME, DEBU); Potaro River vic., 05°9ʹ56ʺN, 059°46ʹ43ʺW, 1° rainforest, 680 m, human dung pitfall trap, 19–20 Oct 2004, B. Hubley (1♂, 1♀, DEBU) . VENEZUELA: Bolívar: km 40 Santa Elena Icabaru Rd. , 100 m, 4–6 Aug 1986, B. Bill (1♂, DEBU) ; ditto, 220 m (1♀, DEBU) , ditto, 1000 m (1♀, DEBU) .

Etymology: This name refers to the weakened or broken up anteroventral linkage of the epandrium (Latin ‘fractus’: broken, fractured; Latin ‘cinctum’: girdle, belt, zone).

Comments: This species seems to be uncommon, but has been collected at low to mid elevations in several South American countries including Ecuador, Guyana and Venezuela. It can be easily identified by the wing venation and WIPs, which are also important synapomorphies linking this member of the basal lineages to the derived clade. The male cerci of B. fractacincta are small, thin and pointed even when compared to B. ramus , and are always flexed inwards on pinned specimens.