Blepharomyia brevicornis, Shima & Abe & Libra, 2021

Shima, Hiroshi, Abe, Tomokazu & Libra, Martin, 2021, Tachinid flies (Diptera: Tachinidae) reared from deciduous plant-feeding lepidopteran larvae at Hokkaido University Tomakomai Forest (Japan), with descriptions of three new species, Zootaxa 5060 (2), pp. 275-295 : 276-283

Blepharomyia brevicornis sp. nov.

( Figs 1–2 , 7–12 , 35–36 )

Diagnosis. A medium-sized voriine tachinid. Prosternum and proepisternum bare; frons at most 1/4 of head width in male, 1/ 3.5 in female; one outwardly directed orbital seta; parafacial with a row of strong setae and with at most a few hairs on upper portion; antenna with postpedicel about two times as long as pedicel in male and female, arista bare, 2nd aristal segment at most 2 times as long as wide; costal spine distinct; 1st and 2nd costal sectors setulose dorsally and ventrally; vein R 4+5 with 4–5 fine setulae from base to 2/5 way to r-m crossvein; wing cell r 4+5 open.

Description. Body length: 6.1–6.8 mm.

Male. Head black, with grayish pruinosity, face more whitish and occiput darker; frontal vitta black, appearing silvery brownish when seen from front; antenna and palpus black. Frons at narrowest point about 0.25 of head width (0.67–0.69 of single eye width); frontal vitta widened anteriorly, about 4/5 as wide as fronto-orbital plate near middle; parafacial slightly swollen, narrowed below, 0.60–0.65 as wide as postpedicel at middle in horizontal position (0.45–0.55 in profile); frontal length slightly more than facial length in profile (4:3.5); face well excavated, lower margin not warped forward, about 1/2 as wide as long between vibrissae; facial ridge not visible in profile; gena 0.33–0.35 of eye height in horizontal position (0.22–0.25 in profile); occiput noticeably bulged. Inner vertical seta strong, slightly curved inward, about 4/5 as long as eye height; outer vertical seta indistinct from long fine occipital setae; ocellar setae fine hair-like, subequal in length to postvertical seta; 1 pair of postvertical setae, cruciate apically; 2 postocellar setae; 1 outwardly directed orbital seta, about 2/3 as long as inner vertical setae; 6–7 frontal setae, upper setae stronger and lowest seta inserted nearly level with middle of pedicel; a row of 5–7 rather long hairs on fronto-orbital plate outside row of frontal setae; parafacial with a row of 7–9 strong, down-curved setae increasing in length toward lower portion; vibrissa nearly level with lower margin of face; facial ridge hidden behind parafacial, with 2–3 short setae just above vibrissa; genal dilation with dense long hairs; occiput with dense long black hairs, pale yellowish hairs confined on ventromedian portion. Antenna short and rather wide, falling only slightly short of lower margin of face; postpedicel about 2 times as long as wide and 3.5 times as long as pedicel; arista thickened on basal 1/2, 2nd aristomere about 2 times as long as wide. Palpus slender, weakly swollen apically, about 2/3 as long as postpedicel. Eye with dense pale yellowish hairs.

Thorax black in ground color, scutum and scutellum with thin grayish pruinosity, pruinosity denser on postpronotal lobe, notopleural area and pleura; 2 very broad outer and 2 narrow inner longitudinal vittae rather distinct on presutural area and postsutural scutum. Five postpronotal setae, basal 3 setae set in a triangle; 2 presutural and 3 postsutural acrostichal setae; 3 presutural and 3 postsutural dorsocentral setae; 3 postsutural intra-alar setae; 3 supra-alar setae, 1st seta nearly as long as 3rd seta and longer than notopleural setae; prosternum, proepisternum, katepimeron and anatergite bare; 3 katepisternal setae; anepimeral seta fine but well developed, almost extending to posterior margin of upper calypter; scutellum with a pair of short, suberect discal setae and 3 strong marginal setae, lateral seta absent; discal setae about 5/6 as long as scutellum; basal setae about 1.5 times as long as scutellum, subapical setae about 2 times as long as scutellum, apical setae about 1.7 times as long as scutellum; distance between bases of subapical scutellar setae about 2 times that between basal and subapical setae. Wing hyaline, weakly tinged with pale yellow especially on basal area; tegula black, basicosta dark brown; calypter translucent pale yellowish brown; halter yellowish brown; 1st and 2nd costal sectors setulose above and below, sometimes basal portion of 3rd costal sector also setulose; costagial seta (seta(e) arising from base of wing between basicosta and costagial break) strong, extending well over humeral crossvein; costal spine about 2 times as long as costal setulae; 2nd costal sector about 1/3 as long as 3rd and 4/5 of 4th; vein R 4+5 with several setulae from base to 1/3–2/5 way to r-m crossvein; vein M from dm-cu crossvein to bend about 1.3 times distance between bend and wing margin; last section of vein CuA 1 about 3/4 as long as dm-cu crossvein; crossvein CuA 2 well developed; vein CuA 2 +A 1 obliterated before wing margin. Legs black, pulvilli pale yellowish; fore tibia with 3 preapical dorsal setae, anterodorsal seta longest, a row of 5–6 anterodorsal and 2 posterior setae; mid tibia with 2–3 anterodorsal, 2 posterodorsal and 1–2 ventral setae; hind tibia with a row of irregular-sized, strong anterodorsal, 2–3 posterodorsal and 3–4 posteroventral setae, and with 2 preapical dorsal and 1 apical anteroventral setae; claws and pulvilli slightly shorter than 5th tarsomere.

Abdomen black in ground color, dorsum with very thin grayish pruinosity on syntergite 1+2, rather thin pale yellowish pruinosity on anterior 1/2–1/3 of 3rd tergite and entire 4th and 5th tergites, pruinosity with tessellate appearance and sometimes thinner on posterior portion of 4th tergite; venter evenly covered with pale yellowish gray pruinosity on syntergite 1+2 to 5th tergite. Hairs on dorsum fine dense and somewhat recumbent on syntergite 1+2 and 3rd tergite, rather sparse and suberect on 4th tergite and still sparse and erect on 5th tergite; syntergite 1+2 excavated to anterior 1/2, with a pair of strong median marginal setae and 2–3 lateral marginal setae; 3rd tergite with a pair of rather short median discal setae, 2 rather fine lateral discal setae, a pair of strong median marginal setae and 3–4 strong lateral marginal setae; 4th tergite with a pair of strong median discal setae, 2–3 lateral discal setae and a row of strong marginal setae; 5th tergite with regular rows of strong discal and marginal setae; 5th sternite with a long and narrow postero-median cleft occupying almost posterior 3/4 of sternite, median membranous plate short and wide, posterior lobe with many short hairs on anterior portion and several long hairs on posterior margin. Terminalia: Cerci in dorsal view weakly narrowed from middle to apical 1/4, apex slightly widened and rounded, in lateral view weakly curved and pointed ventrally at apex; surstylus in lateral view narrowed to apex, with fine short hairs; pregonite flat; postgonite long, as long as basiphallus plus epiphallus; distiphallus long, with ventromedian membrane, dorsal sclerite flat and extending to posterior 4/5 of distiphallus, ventral sclerite widened apically in lateral view; ejaculatory apodeme rather large.

Female. Differing from male as follows: Frons at narrowest point 0.32–0.33 of head width (0.95–1.00 of eye width); 2 subequally long proclinate orbital setae, slightly longer than reclinate orbital seta; parafacial about 0.33 as wide as postpedicel at middle in profile (0.5 in horizontal position); gena 0.33–0.35 of eye height in horizontal position (0.25–0.27 in profile); antenna falling short of lower margin of face by about 1/2 length of pedicel; postpedicel about 2 times as long as wide and about 3 times as long as pedicel; 2nd aristomere as long as wide. First and 2nd costal sectors of wing with only 1–2 fine hairs or bare above; claws and pulvilli at most 1/2 as long as 5th tarsomere. Abdominal dorsum with more broadly and densely tessellate grayish pruinosity. Terminalia: Sixth tergite entire, semicircularly convex on anteromedian dorsal portion, with a row of strong setae on posterior margin; 6th sternite nearly as long as 6th tergite; 6th spiracle on anteroventral portion of 6th tergite, 7th spiracle on membrane just behind posterosubmedian portion of 6th tergite; 7th tergite narrowly separated mid-dorsally into quadrate hemitergites, nearly as long as 6th tergite, with a row of some strong setae dorsally and several fine setae ventrally on posterior margin; 8th tergite reduced to a small, nearly triangular hemitergite, without hairs; 8th sternite rather well expanded posteromedially, with many minute hairs on posterior portion; epiproct absent; hypoproct broad, semicircular.

Puparium ( Figs 35–36 ). Length 5.7–6.7 mm, width 2.3–2.7 mm. Reddish brown; surface with very minute wrinkles, especially on last two segments; rather weakly narrowed to posterior portion; posterior spiracles black, raised above obliquely on posterior portion of puparium, each spiracle divided transversely into two tubercles with a shallow median groove on which a median cicatrix (button) is present, each tubercle with 4 sinuate spiracular slits.

Etymology. The specific name refers to the short antenna of this species, from the Latin adjective brevis (short) plus the Latin noun cornu (antenna) and adjectival suffix is (with).

Type material. Holotype male*: Japan, Hokkaido / Tomakomai, Toma- / komai Experimental Forest // 10.vi.2014, (emerged) / ex Erannis golda / M. Libra & T. Abe ( TOC7818 ) ( HUM).

Paratypes *: 1 male, same data as holotype except date, 30.v.2014 ( TOC 02699) ; 3 males, 2 females, same data as holotype [ TOC 06975 (1 male, 1 female); TOC 07468 (1 male); TOC 07820 (1 female); TOC 08207 (1 male)] ; 1 female, same data as holotype except date, 28.v.2014 ( TOC 03837) ; 1 male, same as preceding, 9.vi.2014 ( TOC 08423) ; 1 female, same as preceding, 19.vi.2014, ( TOC 10077) ; 1 female same data as preceding except host, ex Orthosia odiosa ( TOC 10082) ( KUM, HUM, SMNS, USNM) ; 1 male, 1 female, Japan, Honshu , Kanayama, Masutomi, 26.v.1975, A. Nakanishi & J. Emoto, Malaise trap ( KUM)

Additional material*. 1 male (shrunken), 10.vi.2014, same data as holotype ( TOC 07820) ; 1 puparium (not emerged), 19.vi.2014, same data as holotype except host, ex Orthosia odiosa ( TOC 10082) ; 1 male (shrunken), same as preceding except date and host, 30.v.2015, ex Catocala lara, M. Libra & T. Abe ( TOC 22656) ( HUM) .

Other parasitoids*. 1 hymenopteran ex B. brevicornis (puparium) parasitic on Erannis golda (pupa), 19.vi.2014, M. Libra & T. Abe ( TOC 07887).

Hosts. Lepidoptera , Geometridae : Erannis golda Djakonov. Noctuidae : Catocala lara Bremer , Orthosia odiosa (Butler) .

Remarks. The genus Blepharomyia Brauer & Bergenstamm is known from four species in the Palearctic Region and two in the northern Nearctic. The Nearctic species have characteristically yellowish tibiae ( Coquillett 1897: 53, Curran 1927:149), in contrast to the Palearctic ones, which all have black tibiae. Only one endemic species, B. foliacea Mesnil, 1975 ( Figs 3–4 ), was previously known from Japan. The new species is similar to the European B. pagana ( Meigen, 1824) ( Figs 5–6 ), but differs from it in having a less apically widened postpedicel and a narrower frons and narrower gena in the male. These three species can be distinguished as follows:

1. Antenna with postpedicel widened apically or straight, at most 3.5 times as long as pedicel; 2nd costal sector about 1/3 as long as 3rd costal sector; wing vein R 4+5 setulose dorsally at most halfway to r-m crossvein.............................. 2

- Postpedicel elongate and strongly widened apically and rounded at apex, 5.5 times as long as pedicel in male; 2nd costal sector at most 2/5 as long as 3rd; wing vein R 4+5 setulose dorsally at least halfway to r-m crossvein (female unknown)................................................................................................. B. foliacea Mesnil

2. Frons 0.31–0.32 of head width in male, about 0.30 in female; antenna with postpedicel about 1.6–1.7 times as long as wide in male, in female not apically widened, about 2 times as long as wide and 3 times as long as pedicel; parafacial between row of strong setae and eye with at least a row of fine hairs on upper portion............................ B. pagana (Meigen)

- Frons about 0.25 of head width in male, 0.32–0.33 in female; postpedicel not widened apically in male and female, about 2 times as long as wide in male and female and 3.5 times as long as pedicel in male and 3 times in female; parafacial between row of strong setae and eye with at most several fine hairs on upper portion......................... B. brevicornis sp. nov.

The hosts of the three European Blepharomyia species were reported in Tschorsnig (2017). They are species of Geometridae , Noctuidae and Notodontidae . The present new species is a parasitoid of Geometridae and Noctuidae deciduous feeders in the canopy. According to published reports, Blepharomyia species are ovolarviparous, laying incubated eggs directly on the host’s body ( Herting 1965; Haraldseide 2015). This is true also for B. brevicornis sp. nov. This species appears to usually be a solitary parasitoid, but it is sometimes gregarious with up to two parasitoids per host eclosed in this study, as reported for the European species B. pagana by Herting (1965: 243, as B. amplicornis [Zetterstedt]). Mature larvae of B. brevicornis sp. nov. emerge from the host’s body and pupate under leaf litter or in the soil. It was not confirmed in this study whether B. brevicornis kills its host during the larval stage, as has been documented for B. pagana ( Herting 1965: 256, as B. amplicornis ).

Figures

FIGURES 1–6. Adult males of Blepharomyia spp. 1, 3, 5. Habitus in lateral view. 2, 4, 6. Head in lateral view. 1–2. Blepharomyia brevicornis sp. nov. (paratype, Hokkaido, Japan). 3–4. Blepharomyia foliacea Mesnil (Hokkaido, Japan). 5–6. Blepharomyia pagana (Meigen) (Germany).

FIGURES 7–12. Male and female terminalia of Blepharomyia brevicornis sp. nov. (paratypes, Hokkaido, Japan). 7. Male 5th abdominal sternite in ventral view (hairs omitted on left side). 8. Epandrium, cerci and surstylus in dorsal view (hairs omitted). 9. Same in lateral view (hairs omitted on epandrium and cercus). 10. Hypandrium, pregonite, postgonite and phallus in lateral view. 11. Female terminalia in lateral view. 12. Same in ventral view (hairs omitted). Scale bars: 0.1 mm.

FIGURES 35–44. Puparia. 35–36. Blepharomyia brevicornis sp. nov. (paratype, Hokkaido, Japan). 37–38. Ctenophorinia grisea Mesnil (Hokkaido, Japan). 39–40. Cyzenis equifacialis sp. nov. (paratype, Hokkaido, Japan). 41–42. Cyzenis tetrasetosa sp. nov. (paratype, Hokkaido, Japan). 43.44. Eulasiona zimini Mesnil (Hokkaido, Japan). 35, 37, 39, 41, 43. Lateral view. 36, 38, 40, 44. Posterior apex in lateral or posterior view.