Macrostomus rodriguezi, Rafael & Marques, 2019

Rafael, José Albertino & Marques, Dayse Willkenia Almeida, 2019, Five new species of Macrostomus Wiedemann and a checklist of Empididae (s. str.) (Diptera) from Bolivia, Zootaxa 4567 (2), pp. 251-275 : 262-264

Macrostomus rodriguezi sp. nov.

( Figs 8 A–O, 9A–D)

urn:lsid:zoobank.org:act:B5F934A3-F918-4639-B884-9B7C688A5F8C

Diagnosis. All coxae somewhat white to light yellow. Wing hyaline, slightly brown infuscation at pterostigma. Veins M 1 and M 2 entirely evanescent, distal half of M 4 and apex of CuA+CuP evanescent. Tergite 8 short with distal sinus. Sternite 8 with indistinct small saddle-shaped projection posterodorsally. Epandrium with posterodorsal lobe longer than anterodorsal lobe. Anterior cercus emitting mesially one large and flat cercal bridge connected medially; posterior cercus inwardly curved, simple, acuminate distally; hypandrium well sclerotized, almost same width throughout, with 5 equally spaced posterior setae; distally with a pair of subapical protuberances anteriorly. Ejaculatory apodeme trilamellar. Female sternite 8 highly modified, very thin mid-longitudinally at median third; in lateral view widened distally; genital fork narrow, slightly wider at apex.

Description. Holotype ♂ ( Fig. 8A ). Body length 2.5 mm; wing length 2.5 mm. Specimen from alcohol. Frons shiny black, slightly wider than width of anterior ocellus. One pair of proclinate ocellar setae. Face as wide as frons, widening ventrally. Postcranium shiny black, entirely and sparsely gray pruinose. Inner vertical and outer vertical setae subequal in length to ocellar setae and to uniseriate postocular row of setae; occipital setae restricted to dorsal half. Gena with 3–4 small setae and postgena with 2–4 minute setae. Antenna velvety brown with postpedicel short setulose. Proboscis yellow. Palpus yellow. Thorax shiny black, more distinctly gray pruinose on disc of scutum and scutellum; mesopleuron slightly yellow-brown adjacent to all coxae. Thoracic chaetotaxy: 5 antepronotals small; 1 postpronotal stout, 1 weak; 4 dorsocentrals; 1 presutural supra-alar; 1 postsutural supra-alar; 1 postalar; 2 proepisternals weak; 2 notopleurals, posterior stouter; 2 pairs of scutellars, outer pair weaker; 5 laterotergitals. Legs ( Fig. 8A ) shiny yellow with distal 1/5 of hind femur, entire hind tibia and tarsus light brown. All coxae slightly paler, somewhat white to light yellow. Hind femur with 1 anteroventral seta at base of distal fourth; hind tibia with 4 slender dorsal setae, median weaker; hind tarsomere 1 with 1 median slender dorsal seta. Wing hyaline, slightly brown infuscated at pterostigma. Veins M 1 and M 2 entirely evanescent, distal half of M 4 and apex of CuA+CuP evanescent. Last section of vein M 4 longer than dm-m. Cell dm short and somewhat truncate. Halter whitish. Abdomen shiny black. Tergites 1–3 with slightly longer setae posteriorly. Tergite 8 ( Fig. 8C ) with distal sinus. Sternite 8 ( Fig. 8D ) with indistinct small saddle-shaped projection posterodorsally. Tergite 8 and sternite 8 articulated dorsal/ventrally ( Fig. 8B ). Epandrium ( Fig. 8E ) with posterodorsal lobe longer than anterodorsal lobe. Anterodorsal cleft minute; anteroventral cleft as unsclerotized area. Anterior cercus ( Fig. 8F ) well sclerotized, with short setae and distinct protuberance dorsally; when viewed anteriorly ( Figs 8H ) emitting mesially one large and flat cercal bridge connected medially; when viewed dorsally ( Figs 8I, J ) expanded ventrally and connected with upper lobe of hypoproct. Median cercus ( Figs 8F, G ) semi globose, backwardly directed with longer setae dorsally. Posterior cercus ( Figs 8F, G ) inwardly curved, simple, acuminate distally. Ventral projection of cercus ( Figs 8K, L ) downwardly directed, transversally placed, setose distally, slightly touching each other by small subapical projection. Dorsal lobe of hypoproct fused with mesial cercal bridge expansion of anterior cercus, somewhat inconspicuous, but notable by elongate and slender setae ( Figs 8I, J, L ); ventral lobe of hypoproct distinctly setose. Hypandrium ( Figs 8M, N ) well sclerotized, almost same width throughout, with 5 equally spaced posterior setae (basal one broken); distally with pair of subapical protuberances anteriorly. Ejaculatory apodeme ( Fig. 8M ) trilamellar. Phallus slightly longer than hypandrium.

Female. Body length 2.5 mm; wing length 2.4 mm. Frons wider than width of anterior ocellus, wider than in male. Face as wide as frons, slightly divergent apically. Wing slightly wider and distinctly more infuscate at costal and distal margin than in male. Sternites 1 – 7 as in Fig. 9A . Tergite 8 with sclerotized basal belt, no basal sinus but with deep distal sinus ( Fig. 9C , inferior piece). Sternite 8 ( Figs 9B, C ) highly modified, very thin midlongitudinally at median third; in lateral view widened distally. Genital fork ( Fig. 9D ) narrow, slightly wider at apex. Genital chamber membranous.

Geographical records. Bolivia (La Paz).

Type material examined. HOLOTYPE ♂: “ BOLIVIA, La Paz, Sarampionim [sic], 23.ii.2005, Arm.[adilha] Malaise, J. Rodriguez ”; “ Holotype ♂ Macrostomus rodriguezi Rafael & Marques ” ( Fig. 8O ) (CBF). PARATYPES: Bolivia: same data as holotype (6♂ 1♀, CBF, 6♂, INPA) ; La Paz, Chulumani, cloud forest, above 2000 m, Chulumani, 30.iii. [19]79, QR code: NHMUK 0 10864525 (1♂, NHMUK) ; La Paz, Chulumani, 1600 m, R. Portugal’s Finca, 16°22′S– 67 ° 30′W, 30.iv.1997, L. Masner (1♂, 1♀, CNC) .

Holotype condition. Good, pinned.

Etymology. The specific name is in honor of Dr. Jaime Ivan Rodriguez Fernandez, collector of the specimens.

Remarks. Macrostomus rodriguezi sp. nov. is tentatively included in the M. limbipennis species-group, however, it differs mainly by 1 pair of ocellar setae and epandrium with posterodorsal lobe longer than anterodorsal lobe. In the key presented by Rafael & Cumming (2012), this species runs to couplet 4 separating M. nigriventris (Macquart) from M. nitidus Rafael & Cumming , but it differs from both by tergite 8 without median projection at distal margin (versus both with median projection), by the hypandrium with apex approximately same basal width (versus twice or three times basal width). In addition, the female of M. rodriguezi sp. nov. has the terminalia rather similar to the known female specimens of the M. limbipennis species-group, such as M. inflatus Rafael & Cumming that also has sternite 8 highly modified, very thin mid-longitudinally and widened distally and as in M. nitidus Rafael & Cumming that has the genital fork as a small rod.

Figures

FIGURE 8. Macrostomus rodriguezi sp. nov., paratype ♂. A. Habitus, lateral view; B. Apex of abdomen, lateral view; C. Tergite 8, dorsal view; D. Sternite 8, ventral view; E. Epandrium detached, lateral view; F. Terminalia, epandrium removed, left lateral view; G. Terminalia (Hypandrium and phallus detached), right lateral view; H. Cercal bridge of anterior cercus and subepandrial sclerite, anterior view; I. Cercal bridge of anterior cercus, anterior view; J. idem, in an different angle; K. Apex of ventral projection of cercus, anterior view; L. idem, in a different angle; M. Hypandrium, ejaculatory apodeme and phallus, lateral view; N. Hypandrium, posterior view; O. Holotype labels. Scale bars, figure A = 1 mm; B–N = 0.1 mm. Abbreviations: cbrd, cercal bridge; DHyL, dorsal hypoproctal lobe; Tg, tergite; St, sternite; VHyL, Ventral hypoproctal lobe; vpc, ventral projection of cercus.

FIGURE 9. Macrostomus rodriguezi sp. nov. paratype ♀. A. Sternites 1–7, ventral view; B. Apex of abdomen, lateral view; C. Tergite 8 and tergite 9+10 (inferior piece), dorsal view and sternite 8, ventral view; D. genital fork and genital chamber, ventral view. Scale bars, figure A = 1 mm; B–D = 0.2 mm. Abbreviations: Tg, tergite; St, sternite.