Bregmosina bucki, Marshall, Stephen A., 2013

Marshall, Stephen A., 2013, Bregmosina, a new Neotropical genus of Limosininae (Diptera: Sphaeroceridae), Zootaxa 3641 (3), pp. 260-270 : 262

Bregmosina bucki new species

Figs. 1–6

Description. Length (antennal base to wing tip) 2.8–3.0 mm. Head: Eye height 2.5–2.8X genal height. Two welldeveloped orbital bristles, lower at least 0.7X length of upper.

Thorax: Tarsomeres 2–5 of fore leg short and flat, more or less quadrate; tarsomeres 2, 3, 5 equal in length, indistinctly wider and shorter than tarsomere 1; tarsomere 4 shorter; tarsomeres 4 and 5 strongly flattened. Tarsomeres 1 and 2 of hind leg strongly swollen; second tarsomere as long as tarsomeres 3, 4, and 5 combined. Mid tibia with a long proximal anterodorsal bristle and 3 or 4 distal dorsal bristles, including a long anterodorsal, a long dorsal, a short posterodorsal (length equals tibial width), and (usually) a small dorsal bristle above the long distal dorsal. Posterior quarter of katepisternum yellow to pale brown, anterior part brown. Wing: Second costal sector 0.7–0.8 times as long as third, R2+3 gently and evenly curved up to apex, not sinuate.

Female abdomen: Syntergite 1+2 dark posteriorly, anterior margin with a large medial pale area. Sternite 10 continuously sclerotized along posterior and lateral margins, otherwise pale. Spermathecae spherical with a broadly tapered base, length slightly less than sternite 7. Tergite 8 dorsally shortened, shorter than tergite 7 at middle, with one pair of long posterolateral bristles. Cercus short, subequal in length and width, with a long apical bristle.

Male abdomen: Sternite 5 large, pale medially except for a shining, deeply concave posteromedial sclerite, posteromedial portion of sclerite flanked by long-setose bands ending in short, quadrate lobes. Ventral part of sternite 6 narrow and dark, with a prominent anterior process at level of posteromedial sclerite of sternite 5. Cerci bulbous-subquadrate, fused in dorsal ¾. Surstylus with a prominent lateral ridge at base, flat in distal portion, in lateral view elongate-rectangular with a sharp anteroapical toe. Postgonite broad basally, tapered to a narrow distal lobe. Basiphallus short, distiphallus with a broad cylindrical base expanding out to very broad bilobed lateral plates distally. Ring sclerite incomplete.

Type material. Holotype (male, debu00131554, INBIO) and 9 paratypes (53, 4Ƥ, DEBU, INBIO) COSTA RICA. Volcán Tenorio, N slope nr. Bijagua Biological Station, 700 m, pans in tree fall, 18.vi.2000, Buck and Marshall.

Other material examined: COSTA RICA. Estación Cacao, Guanacaste, 1100–1290 m, 15.ii.1996, S.A. Marshall (1Ƥ, INBIO).

Etymology. Bregmosina bucki is a patronym honoring Matthias Buck, an esteemed colleague who helped initiate this work while he was at University of Guelph.

Figures

FIGURES 1 – 6. Bregmosina bucki. 1, female terminalia lateral; 2, spermathecae; 3, male wing; 4, male terminalia ventral; 5, epandrium and associated structures left lateral; 6, aedeagus and associated structures left lateral. Abbreviations: T 7, T 8, S 5, S 7, S 8, sternites and tergites; P, phallapodeme; PG, postgonite; H, hypandrium; C, cercus; D, distiphallus; SU, surstylus.