Ectophasiopsis arcuata ( Bigot, 1876 )

Dios, Rodrigo de V. P. & Nihei, Silvio S., 2017, Taxonomic revision of the Neotropical genus Ectophasiopsis Townsend, 1915 (Diptera: Tachinidae: Phasiinae), European Journal of Taxonomy 334, pp. 1-27 : 5-9

Ectophasiopsis arcuata ( Bigot, 1876)

Figs 2 A–E, 4–6

Trichopoda arcuata Bigot, 1876: 397 . Lectotype ♂, BMNH (other “ syntypes ” misidentified; see discussion below). Type locality: “ Chile ” (examined).

Ectophasiopsis chilensis Townsend, 1915: 439 . Syntypes, two ♂♂ and one ♀, USNM. Type locality: “ Chile ”. (syn. by Aldrich 1934).

Trichopoda arcuata – Townsend 1893: 70; 1915: 439. — Guimarães 1971: 12.

Ectophasiopsis chilensis – Townsend 1915: 439; 1936: 55; 1938: 47. — Aldrich 1934: 12. — Guimarães 1971: 12.

Ectophasiopsis arcuata – Aldrich 1934: 12. — Wolcott 1948: 471. — Guimarães 1971: 12.

Diagnosis

Ectophasiopsis arcuata closely resembles E. gradata comb. nov. as both have the antennal axis longer and fronto-orbital plate at the lunule level and parafacial enlarged, but differs from other species by the thorax being long setulose laterally and dorsally and dorsocentral setae 2+2 or 3+2 (short presutural setae).

Type material examined

Lectotype

CHILE: ♂, T. arcuata ( BMNH) by present designation. “ Syntype ” (white label with blue border); [“Brauer / Wien. CVII. / (No. 105)” “ Trichopoda / arcuata Bigot / syntype ♂ / Chile, Plata / ex. Bigot Coll: / B.M. 1960-539”; “ T. arcuata / Chili, Plata. J. Bigot [white with black border]” “BMNH (E) # / 230866 ”; “ Lectotype / Ectophasiopsis arcuata (Bigot) / R. Dios des. 2016”].

Additional material examined

CHILE, Región Metropolitana: 1 ♂, 1 ♀, Santiago, “Puelma” ( ZMHU). – Región del Maule: 1 ♂, Cauquénes, 20 Nov. 1997, S. Schönemann leg. ( ZMHU) (dissected); 1 ♀, ditto, 6 Aug. 1999 ( ZMHU); 1 ♂, Caiablo or Carablo (illegible), Jan. 1954, E.P. Reed leg. ( CAS).

Redescription

Male ( Fig. 5 )

BODY LENGTH. 6.9 mm (lectotype), 7.3–7.6 mm (n = 3).

COLORATION. Frontal vitta yellowish-tawny with region around ocellar triangle dark brown to black. Ocellar triangle black. Fronto-orbital plate light-tawny to orange with silver and light-golden pruinosity. Parafacial and gena light-tawny-yellow with silver pruinosity. Antenna tawny-yellow, with area close to joints and posterior part of postpedicel slightly yellowish-orange. Palpus tawny to light-tawny. Presutural scutum dark brown to black (lacking pruinosity probably due to effects of preservation), with light-golden pruinosity delimiting two diverging median black stripes fused anteriorly and two triangular lateral black spots. Postpronotal lobe dark brown with silver pruinosity. Postsutural scutum dark brown, with light-golden pruinosity delimiting two central small triangular black spots and two outer long triangular black spots. Scutellum dark brown to black with silver pruinosity. Thorax laterally brown to black with silver pruinosity. Wings with orange-yellow radiation from the base to little beyond vein r-m anteriorly and little beyond vein bm-cu posteriorly, followed by infuscate band ranging from anal lobe to almost apex of cell r4+5 and posterior border hyaline; hyaline part extending to cell dm and r4+5. Calypters orange-yellow, basally lighter. Legs brown, coxae with silver pruinosity; pulvilli pale-tawny to brown. Abdomen yellow-orange; tergite 1 dark brown; tergite 4 posteriorly dark brown; dorsal median longitudinal dark brown line between tergite 1 and 4; tergite 5 dark brown, but orange on posterior lateral margins and thin median posterior dark brown line; tergite 6 orange yellow with thin median anterior dark brown stripe; silver and light-golden pruinosity on tergites 5 and 6, and scarcely on tergite 4 posteriorly. Abdomen ventrally with almost same pattern as dorsally, without pruinosity.

HEAD. Ratio of head width / thorax width dorsally of 1.35. Ratio of head length / head width 0.5. Ratio of frontal vitta width at level of lunula / width at vertex level 0.8. Fronto-orbital plate width subequal to frontal vitta width at level of lunula. Antennal axis long, fronto-orbital plate at lunule level and parafacial enlarged. Ratio of gena height / eye height 0.16.

THORAX. Acrostichal setae apparently 0+0 (area damaged by pin; 0+ 1 in non-types, sometimes weak); dorsocentral setae 3+2; all thorax long setulose, almost same length as setae. Postpronotal lobe damaged by pin (3 setae on non-types). Two katepisternal setae.

WING. Subtriangular, anal lobe slightly larger. Ratio of wing length / wing maximum width 2.37. Crossvein dm-cu straight.

LEGS. Hind femur with row of anterodorsal setae, one preapical anteroventral seta and row of posteroventral setae on apical third, some setae slightly flattened; hind tibia with one median anteroventral seta and one median posterodorsal setae; row of longer feather-like setae covering apical 0.76, length of longest feather-like seta 1.77 times the tibial width.

ABDOMEN. Elliptical, little rounded, dorsoventrally flattened. No differentiated setae, only small setae laterally on tergites posterior margins. Ratio of abdomen length / thorax length 1.39. Ratio abdomen width/ thorax width 1.33. Ratio of abdomen length / abdomen width 1.37.

TERMINALIA ( Fig. 2 A–E). Cerci midventral opening lateral border not visible in dorsal view. Postgonite almost not enlarged distally in posterior view, subequal in its length. Phallapodeme subequal in its length, slightly widened apically. Basiphallus as an incomplete ring, open posteriorly.

Variation

COLORATION. Frontal vitta and postpedicel sometimes darker. Presutural scutum with median black stripes fused. Postpronotal lobe lighter brown. Postsutural scutum sometimes posteriorly all dark brown to black. Wing with orange-yellow coloration pale; infuscate band more diffuse, cell dm posteriorly weak infuscate and hyaline. Abdomen with dorsal median longitudinal dark brown line wider, tergite 6 without brown markings, and varying pruinosity.

HEAD. Ratio of head width/ thorax width dorsally 1.35 to 1.52. Fronto-orbital plate width little wider than frontal vitta width at level of lunula. Ratio of gena height / eye height 0.13 to 0.16. Thorax. Dorsocentral setae 2+2.

WING. Ratio of wing length / wing maximum width 2.19 to 2.57.

LEGS. Fore femur with rows of short posterodorsal and posteroventral setae sometimes very weak. Hind femur with preapical anteroventral seta not differentiated and row of posteroventral setae on apical third with varied sizes and lengths. Row of long feather-like setae on hind tibia covering apical 0.76 to 0.9 of tibia, and length of longest feather-like seta 1.51 to 1.77 times tibial width. Abdomen. Ratio of abdomen length / thorax length 1.32 to 1.39. Ratio abdomen width / thorax width 1.33 to 1.68. Ratio of abdomen length / abdomen width 1.15 to 1.37.

Female ( Fig. 6 )

Differs from male as follows:

BODY LENGTH. 6.6–7.3 mm (n = 2).

COLORATION. Head with silver pruinosity only and background color usually darker. Thorax darker, with silver pruinosity, sometimes scarce as two longitudinal thin lines; Postsutural scutum all dark brown to black posteriorly. Wings sometimes paler orange-yellow, extending a little less than in males; hyaline border wider and clearly defined. Abdomen yellow-orange, dorsal median longitudinal dark brown line ending in middle of tergite 1+2; tergite 4 with median dorsal dark brown black triangle pointing anteriorly; tergite 5 and 6 dark brown to black.

THORAX. Postpronotal lobe with 2 setae, sometimes a third very weak.

WING. Elliptical.

LEGS. Hind femur with row of posteroventral setae on apical third, never flattened; hind tibia with length of longest feather-like seta 2.11 times tibial width. Claws shorter and curved. Pulvilli shorter, more rounded.

ABDOMEN. Elliptical. Very weakly differentiated median marginal setae on tergite 4 to tergite 6. Slightly shorter (ratio of abdomen length /thorax length 1.21 to 1.28) and narrower (ratio abdomen width / thorax width 1 to 1.2). Ratio of abdomen length / abdomen width 1.31 to 1.6.

TERMINALIA. Due to lack of material, no female was dissected.

Distribution ( Fig. 4 )

Chile, and introduced in Puerto Rico ( Wolcott 1948). The species was also introduced to Easter Island, from mainland Chile ( Ripa et al. 1995)

On the type specimens of E. arcuata and its identity

There has been confusion surrounding the type material of Ectophasiopsis arcuata (7 syntypes). Bigot’s (1876) original description did not state the number of specimens examined nor did he describe any variation (e.g., in the color of the abdomen and wings). Aldrich (1934) examined the types of E. chilensis and E. arcuata , without mentioning their labels and localities. Now we have had the opportunity to study the entire type series borrowed from BMNH and we could observe that actually only one syntype is labeled from “ Chile, Plata” and bears Bigot’s characteristic identification label with the black border (see Crosskey 1971). This syntype is the only one that fits the original description so, in the interests of nomenclatural stability, is designated here as the lectotype of Trichopoda arcuata Bigot, 1876 . The other six syntypes of arcuata are now paralectotypes, but all them were misidentified by Bigot: one is a Trichopoda sp. while the remaining five are E. gradata ( Wiedemann, 1830) comb. nov. These six paralectotypes bear two labels: [“Brauer / Wien. CVII. / (No. 105)”] and [“ Syntype ”] (round label from BMNH), but not Bigot’s identification labels. However, in Verrall’s handwritten notes about Bigot’s type collection, he stated that there were seven specimens in the Trichopoda arcuata type series (Adrian Pont, pers. comm.). It is likely that these six paralectotypes might be Brauer’s further addition to the type series, but we cannot state it with certainty. Therefore, we assume that the seven specimens belong to Bigot’s type series of E. arcuata and it involves three different identities. Townsend (1938) had stated earlier that the types of E. arcuata could represent at least two species.

Figures

Fig. 2. Male terminalia. – A–E. Ectophasiopsis arcuata (Bigot, 1876). A. Epandrium, cerci, surstyli, pregonite and postgonite, posterior view. B. Epandrium, cerci and surstyli, lateral view. C. Phallus, right lateral view. D. Phallus, posterior view. E. Phallus, left lateral view. – F–J. E. gradata (Wiedemann, 1830) comb. nov. F. Epandrium, cerci, surstyli, pregonite and postgonite, posterior view. G. Epandrium, cerci and surstyli, lateral view. H. Phallus, right lateral view. I. Phallus, posterior view. J. Phallus, left lateral view. – K–O. E. ypiranga sp. nov. K. Epandrium, cerci, surstyli, pregonite and postgonite, posterior view. L. Epandrium, cerci and surstyli, lateral view. M. Phallus, right lateral view. N. Phallus, posterior view. O. Phallus, left lateral view. Abbreviations: B = basiphallus (red color); C = cerci; E = epandrium; Ep = epiphallus (red color); Ht = half-tube like plate (blue color); It = sclerotized inner tube (green color); Po = postgonite; Pr = pregonite; Rl = ring-like plate (orange color); S = surstylus. Scale bars: 0.2 mm.

Fig. 5. Ectophasiopsis arcuata (Bigot, 1876), ♂, lectotype, Chile, “Plata”, BMNH. A. Dorsal view. B. Lateral view. C. Head, dorsal view. D. Head, lateral view. E. Abdomen, dorsal view. F. Wing, dorsal view. Scale bars: 1 mm.

Fig. 6. Ectophasiopsis arcuata (Bigot, 1876), ♀, Chile, Santiago, ZMHU. A. Dorsal view. B. Lateral view. C. Head, dorsal view. D. Head, lateral view. E. Abdomen, dorsal view. F. Wing, dorsal view. Scale bars: 1 mm.

Fig. 4. Distribution map of Ectophasiopsis species. E. arcuata (Bigot, 1876) = yellow dots; E. gradata (Wiedemann, 1830) comb. nov. = green dots; E. ypiranga sp. nov. = red dots.