Phyllomya erro (Townsend, 1931) Santis & Mengual, 2024

Santis, Marcelo Domingos de & Mengual, Ximo, 2024, Revision of the Neotropical Phyllomya Robineau-Desvoidy (Diptera: Tachinidae): a new synonymy and additional records, Journal of Natural History 58 (9 - 12), pp. 330-341 : 335-339

Phyllomya erro (Townsend, 1931) comb. n.

Figure 2

Itamintho erro Townsend, 1931a: 330 . References: Guimarães 1971: 96 (catalogue of Neotropical Tachinidae ); O’Hara et al. 2020: 147 (checklist of world Tachinidae ); Santis (2022: 62, taxonomic notes).

Type locality. Brazil, São Paulo, Itaquaquecetuba .

Type material examined. ( Figure 2B ). Holotype female deposited at USNM and labelled as follows: “ Itamintho // erro TT ♀ ” [handwritten] “ ♀ ” “ Itqq.30.XII // on foliage ” [handwritten] “Type” “USNMENT // 01518133” [QR code]. Only the photographs were available for this study.

Diagnosis

This species differs from other New World species of Phyllomya by the following combination of characters: thorax with two katepisternal setae; wing hyaline, with distinct brownish tinge mainly on apical portion; vein R 1 setulose halfway to the wing tip and vein R 4+5 with setulae continuing after the r-m dorsally; lower calypter whitish; abdomen black in ground colour, without discal setae, and bearing whitish pruinosity on anterior 1/3–1/4 of tergites 3 and 4. Phyllomya erro closely resembles the Nearctic species P. fuscicosta Curran, 1927 by sharing postpedicel 2.5× as long as the combined length of scape and pedicel, with postpedicel slender and pubescent arista; and wing hyaline with distinct brownish tinge mainly on apical portion. However, they can be differentiated as follows: P. erro has vein R 1 setulose halfway to the tip (bare in P. fuscicosta ), vein R 4+5 with setulae continuing after crossvein r-m dorsally (only setulose at base o R in P. fuscicosta ), and palpus and labella yellowish (blackish in P. fuscicosta ).

Redescription. Female. Body length (2): about 8.0 mm.

Colouration. ( Figure 2 (A, C–D)). Frontal vitta and ocellar triangle dark brown to black. Head with silvery pruinosity, but slightly brownish on about 1/5 ventrally. Occiput with black setulae. Scape tawny, pedicel light brown. Postpedicel brownish black, but proximal 1/6 tawny. Palpus and labella yellowish. Thorax with mainly silver pruinosity; scutum with four dark vittae, on prescutum the two inner vittae are thinner than the outer, on postscutum, the inner vittae is half the length of the outer, neither reaching the scutellum. Scutellum blackish, without pruinosity. Wing hyaline, with distinct brownish tinge mainly on apical portion. Lower calypter whitish. Legs brown to light brown. Claws brown, pulvilli yellow. Abdomen brownish black with greyish silver pruinosity. Syntergite 1 + 2 brownish black. Tergites 3 and 4 with silvery pruinosity on about 1/4 at the anterior half, and tergite 5 probably without silver pruinosity.

Head. ( Figure 2 (A, D)). Vertex about 0.23× head width in dorsal view. Frontal vitta, at the narrowest point, 0.8× the width of ocellar triangle. Minute proclinate setae on fronto-orbital plate and parafacial. Ocellar setae proclinate and well differentiated from the adjacent setae; postocellar setae proclinate. Inner and outer vertical setae subparallel to convergent. Postocellar setae proclinate. Width of parafacial measured between inner margin of compound eye and antennal insertion 0.6× the width of gena. Facial carina absent. Fronto-orbital plate with two proclinate and one reclinate setae, with 8–9 pairs of proclinate setae; about the same width as frontal vitta and parafacial. Postpedicel slender pubescent, 2.5× the combined length of scape and pedicel. Strong and convergent vibrissae; five to six developed subvibrissal setae. Facial ridge with four setulae on lower third. Lower facial margin not protruding, not visible in profile. Eye about 0.7× the head height. Gena about 0.4× eye height. Palpus slightly clavate, about twice the length of prementum. Labella well developed.

Thorax. ( Figure 2 (A, D)). Notopleuron with equal-sized setae. Two proepimeral setae. Two proepisternal setae. Intra-alar 1 + 3; intra-postalar absent. Supra-alar 1 + 1. Postpronotal lobe with two setae, forming a row. Anepisternum with six strong setae and with one upward directed setulae anteriorly. Scutellum with two pairs of strong setae, one lateral and one apical. Two katepisternal setae. Postalar callus with two large and one smaller setae. Anepimeron with a single long seta. Propleuron and prosternum bare. Anatergite bare. Posterior spiracle with posterior lappet larger than anterior. Wing smoky. Costal spine well developed. Wing cell r 4+5 open at wing margin; length of opening shorter than crossvein r-m. Crossvein dm-cu sinuous. Costagial break with a single seta very long and strong. Base of vein R dorsally and ventrally setulose, vein R 1 setulose halfway to the tip and vein R 4+5 with setulae continuing after the r-m, both dorsally. Vein M 1 gently curved and reaching wing margin close to tip, bent forward to R 4+5, forming an angle slightly less than 90°, and convex after bend. Legs. Fore coxa with many setae anteriorly; fore femur with dorsal and ventral row of setae; fore tibia with dorsal and ventral row of setae. Mid femur with two median anterodorsal setae, two preapicals, one anterodorsal and one posteroventral setae. Hind femur with at least three anteroventral setae on basal half and three ventral setae on basal half and with row of anterodorsal setae; hind tibia with at least three anterodorsal and three posterodorsal setae on median third; fore claws and pulvilli shorter than tarsomeres 5.

Abdomen. ( Figure 2 (A, C)) Abdomen conical, tapering to tip; abdomen with silver pruinosity mostly on anterior half of tergites. Mid-dorsal depression on syntergite 1 + 2 confined to about anterior 1/4. Syntergite 1 + 2 and tergite 3 each with a pair of lateral margin and median marginal setae. Tergites 4 and 5 with a row of marginal setae.

Terminalia . Not dissected, only female holotype was available.

Male. Unknown.

Biology. Unknown.

Remarks

Phyllomya erro comb. n. agrees remarkably well with the generic diagnosis given by Shima et al. (2022), including the potential autapomorphies of the costagial break with at least a single very long and strong setae and vein M 1 gently curved; thus, we confidently place this species within Phyllomya . At the same time, it differs from all other Phyllomya species in having the vein R 1 setulose halfway to the wing tip (bare in other species), and vein R 4+5 with setulae continuing beyond crossvein r-m (reaching at most halfway to r-m in other species).

An additional single female specimen of Phyllomya at the MZSP is known from Brazil and may be a new species allied to P. erro , with which it shares two characters: vein R 1 setulose halfway to the wing tip and vein R 4+5 with setulae continuing apically to crossvein r-m. However, the description of this potential new species awaits the availability of more material. The sampling of Phyllomya in the Neotropics is still a rare occurrence, with only this single specimen and the female holotype of P. erro . New collecting efforts are needed to better understand the distribution and diversity of this genus in the Neotropics.

Distribution. Brazil (São Paulo).

Key to the New World species of Phyllomya (partially based on Curran’s (1927) key to Nearctic species of Phyllomya )

1 Wing dorsally with vein R 1 bare and setulae on vein R 4+5 ending before crossvein r-m ( Figure 1C ); abdominal tergites 3 and 4 with a pair of median discal setae ( Figure 1A ) .............................................................................................................................................. 2

- Wing dorsally with vein R 1 setulose halfway to tip and setulae on vein R 4+5 continuing beyond crossvein r-m ( Figure 2A ); abdominal tergites 3 and 4 without discal setae ( Figure 2C ) ............... ............... P. erro (Townsend, 1931) comb. n. (Neotropical: Brazil)

2 Wing with vein R 4+5 open at wing margin ( Figures 1C , 2A )................................................ 3

- Wing with vein R 4+5 closed just before wing margin.................................................................. ...................................................... P. limata (Coquillett, 1902) (Nearctic: Canada and USA)

3 Parafacial with strong and long setulae, almost as long as subvibrissal setae; abdomen without silver pruinosity laterally, or reduced, at most on anterior 1/5 on syntergite 1 + 2 and tergite 3 .............................................................................................................................. 4

- Parafacial with weak and short setulae, about 1/3 length of subvibrissal setae ( Figure 1B ); abdomen with silver pruinosity laterally, on anterior 1/2 to 1/3 on syntergite 1 + 2 and tergite 3 ( Figure 1C ) ................................................................................. 5

4. Scape and pedicel reddish yellow; postpedicel narrower than parafacial, slightly tapering .................. .................. P. polita (Coquillett, 1898) (Nearctic: Canada and USA)

- Antennae wholly black; postpedicel wider than parafacial, broad, not tapering ............ ........................................................... P. fuscicosta Curran, 1927 (Nearctic: Canada and USA)

5 Thorax with katepisternum bearing three setae; head with antennae with blackish pedicel; palpus yellow; (head figured in Wood 1987, p. 1226) ............................................... ................................. P. washingtoniana (Bigot, 1889) (North America north of Mexico)

- Thorax with katepisternum bearing two setae ( Figure 1C ); head with antennae with reddish pedicel; palpus dark reddish ( Figure 1B ); ......................................................................... ............ P. pictipennis (van der Wulp, 1891) (Nearctic: USA and Neotropical: Mexico)

Figures

Figure 1. A–D. Holotype male of Phyllomya pictipennis (van der Wulp, 1891) (NHMUK). A. Dorsal habitus. B. Head, frontal view. C. Lateral habitus. D. Labels.

Figure 2. A–D. Holotype female of Phyllomya erro (Townsend, 1931) comb. n. (USNM). A. Lateral habitus. B. Labels. C. Abdomen, dorsal habitus. D. Head, frontal view.