Mesoconius tigrinus, Marshall, S. A., 2015

Marshall, S. A., 2015, Mesoconius Enderlein (Diptera, Micropezidae, Taeniapterinae) of Central America, Zootaxa 3914 (5), pp. 525-540 : 536-538

Mesoconius tigrinus new species

Figs. 5A–5G

Description. Size (antenna to wing tip) 16–18 mm. Color: Frons, upper back of head, antenna, and mesonotum black; back of head with a yellow patch; face, parafacial, palpus, and sides of clypeus yellow; middle of clypeus and subantennal spots dark brown. Thoracic pleuron dull yellow to white with three black bands (anterior and posterior bands vertical, middle band diagonal); notum with 2 indistinct longitudinal bands of silvery pruinosity ( Fig. 5B ). Abdominal tergites black with narrow pale bands between them; abdominal pleuron of female with prominent pattern of tapered vertical strips, male pleuron less prominently marked, with a large dark area on pleuron 2 and slightly darkened upper pleural margins on other tergites. Male terminalia (including S8) yellow, female oviscape black. Fore coxa black; fore femur black anteriorly and distally, yellow posteriorly on proximal half; fore tibia black; tarsomeres yellow. Mid femur orange with a broad black basal band and a shorter black distal band, hind femur similar but with white instead of orange on basal half. Mid tibia orange-brown, darker distally; mid tarsus black; hind tibia orange to yellow, hind tarsus with 2 basal tarsomeres white, distal 3 tarsomeres dark brown.

Head: Epicephalon and paracephalon indistinctly striate and shining, epicephala separated by narrow posterior extension of frontal vitta; orbital strips and lower frons rugose and subshining; frontal vitta velvety black, broadly tapered anteriorly and widely separated from anterior edge of frons. Inner vertical bristle well–developed but postocellar and outer vertical bristle absent; Fronto-orbital bristles very small, 1–2 on paracephalon and usually one on orbital strip. Upper face bare, prominently and broadly carinate. Palpus pale yellow.

Thorax: Postpronotal lobe microsetulose except for shining anterior face, with a few scattered small setae. Scutum with pruinose pattern as noted above, otherwise microsetulose with small, scattered dorsocentral and acrostichal setulae. Katatergite yellow; prominent but rounded, without a point or nipple-like process. Vertical row of katepisternal bristles brown, other katepisternal bristles, including long ventral bristles, pale. Fore coxa with an anteroventral tuft of black bristles, other coxae with tufts of mixed golden and black bristles.

Abdomen: Syntergite 1+2 very narrow basally, constriction between syntergites about half as wide as base of T3; length of T1+2 triple length of T3.

Female abdomen: Bursa copulatrix broad, quadrate, rugose, with single and double spermathecal ducts arising from a very short and broad common duct; ventral receptacle finger-like with a distinct head. Single spermathecal duct slightly longer than, and about 2/3 as broad as, double spermathecal duct, smooth until preapical constriction, then wrinkled and weakly sclerotized before ending in small, slightly swollen spermatheca; double spermathecal duct broad and indistinctly reticulate-surfaced until a small swelling where it divides into separate rugose, gently sinuate ducts, each leading to a large oval spermatheca with a narrow invaginated apex that is slightly longer than wide.

Male abdomen: Sternites 1–6 greatly reduced, desclerotized or absent. Sternite 7 with a dark ventral and left lateral linear band; fused broadly with the large, unmodified S8. Epandrium with short anteroventral arms (1/5 of epandrial length); ventral part of epandrium strongly incurved. Hypandrium small, anterior loop narrow. Ejaculatory and aedeagal apodemes large; central body of sperm pump with finely spinulose surface. Basiphallus very small, frame-like; postgonites small, with inconspicuous setae; basal part of distiphallus broadly cylindrical, expanding distally to a large, elongate phallic bulb continuous with a similarly sclerotized tubular distal distiphallus that is slightly shorter than basal basiphallus.

Type material. Holotype (♂ INBC): COSTA RICA. San José province, Moravia, Zurquí de Moravia, north pasture, 1600 m, 16.iv.2013, hand collected, ZADBI –663.

Paratypes ( INBC unless otherwise indicated): COSTA RICA. Cartago, PN Tapanti, Quebrada Segunda, 1150 m, xi.1994, malaise, G. Mora (1 ♀); Cartago, PN Barbilla, Cerro Tigre, 1600 m. 19.v.2001, E. Rojas, L. Chavarria, W. Arana, F. Umaña, L. Chaverri, B. Hernandez (1 ♂); Cartago, Turrialba, PN Barbilla, Cerro Tigre, 1600 m, 24.vi.2001, E. Rojas, F. Umaña (1 ♂); Cartago, PN Tapantí, Quebrada Segunda, 1250 m. xi.1993, malaise, G. Mora (1 ♂). Puntarenas, Buenos Aires, Altamira station, trail to Coca house, 1700 m. 4.iii.–14.iv.2000, malaise, D. Rubi (1 ♀); Puntarenas, Buenos Aires, Altamira station, Cerro Biolley, 1766 m. 3.iii.–13.iv.2000, malaise, D. Rubi (3 ♂); Puntarenas, Monteverde Biological Station, along upper trail, 10°18’7”N 84°48’10”W, 1700 m. 14–18.viii.2010, S.A. Marshall (2 ♂, DEBU); Puntarenas, Monteverde Biological Station, along lower trail, 10°18’7”N 84°48’10”W, 1500 m. 14.viii.2010, S.A. Marshall (1 ♀, DEBU); Puntarenas, Las Tablas, Sabalito, Cerro Quijada de Diablo, 2000 m. 15.viii.2000, M. Alfaro (1 ♂); Puntarenas, Buenos Aires, Altamira station, Cerro Biolley, 1766 m. 14.v.–8.vi.2000, Malaise, D. Rubi (1 ♂); Puntarenas, Buenos Aires, Altamira station, trail to Coca house, 1700 m. 14.iv.–12.v.2000, malaise, D. Rubi (1 ♂); Puntarenas, Monteverde Biological Reserve, 1500 m. 14.vi.2000, tree fall sweep & pans, M. Buck (1 ♀, DEBU); Puntarenas, Buenos Aires, Altamira station, Cerro Biolley, 1766 m. 13.iv–12.v.2000, malaise, D. Rubi (2 ♂, 1 ♀); Puntarenas, Buenos Aires, Altamira station, Cerro Biolley, 1766 m. 4.i.–3.ii.2000, malaise, D. Rubi (1 ♂); Puntarenas, Monteverde, San Luis, Buen Amigo, 1300 m. iv.1995, malaise, Z. Fuentes (1 ♀); Puntarenas, Monteverde Biological Station, lower trail, cloud forest, 11.vi.2000, S.A. Marshall (1 ♂, DEBU). San José, Moravia, Zurquí de Moravia, tower path, 1600 m. 12–19.iv.2013, malaise, project ZADBI (1 ♀); San José, Zurquí de Moravia, 1600 m. 9.x.1990, P. Hanson (1 ♂); San José, Moravia, Zurquí de Moravia, tower path, 1600 m. 26.iv.–3.v.2013, malaise, project ZADBI (1 ♀).

Etymology. Mesoconius tigrinus is named for the tiger–striped abdominal and thoracic pleura.

Comments. Although Mesoconius tigrinus superficially resembles the similarly yellow and black M. hemithorax , these two species differ in many important details, the most obvious of which are the lack of postocellar bristles and the rounded katatergite in M. tigrinus (in contrast with the nipple-like katatergite and well developed postocellars in M. hemithorax ). The stout, short, tubular distal distiphallus of this species is most similar to the greatly reduced distal distiphallus of M. nigrihumeralis . Both M. tigrinus and M. nigrihumeralis are outside the clade including all other Central American Mesoconius .

Mesoconius tigrinus is a close mimic of the sympatric ichneumonid wasp Exetastes tarsalis Cresson.

Figures

FIGURE 5 A – G. Mesoconius tigrinus. A, B, live female (Monteverde); C, spermatheca and associated structures; D, male; E, male terminalia, lateral; F, thorax – abdomen junction to show low, rounded katatergite G, head. Abbreviations: BDP—basal distiphallus, PB—phallic bulb, DDP—distal distiphallus, PG—postgonite.