Trischidocera sauteri Villeneuve

Nihei, Silvio S., 2015, The misplaced genus Trischidocera Villeneuve (Diptera, Tachinidae), Zootaxa 3926 (2), pp. 279-286 : 280-282

Trischidocera sauteri Villeneuve

( Figs 1–3 , 8 )

sauteri Villeneuve, 1915: 94 . Lectotype male lost (formerly in HNHM), one paralectotype male remaining in USNM (lectotypification by Townsend, 1932: 57 with the mention of “Male Ht”). Type-locality: Taiwan, Mt. Hoozan [Kaohsiung Hsien, Fengshan].

atratula Malloch, 1924: 521 (Orectocerina) . Holotype female (BMNH). Type locality: “ Malaya ”. (Synonymy by Townsend, 1939: 357, and confirmed here).

Redescription. Male. Body length: 4.3 mm, wing length: 4.1 mm.

Coloration: Head ( Figs 2–3 ) blackish with weak pale golden pruinosity on frons, fronto-orbital plate, parafacial and gena; face and occiput with silver pruinosity. Antenna blackish. Proboscis blackish. Thorax ( Figs 1, 3 ) blackish with silver pruinosity on pleura and very pale golden pruinosity on scutum, with four non-pruinose longitudinal stripes; scutellum dark brown. Wing ( Fig. 1 ) hyaline, but the membrane tinged with light brown along the veins; calypters white; halter yellowish. Legs ( Fig. 1 ) blackish with some silver pruinosity. Abdomen ( Fig. 1 ) blackish with silver pruinosity on basal half of tergites.

Head ( Figs 2–3 ): Eye bare. Frons with medioclinate (the lower ones) and apparently medioreclinate (the upper ones) setae. Fronto-orbital plate and parafacials with a continuous row of tiny setulae from level of anterior ocellus ventrally to the lower margin of eye, and one short lateroreclinate fronto-orbital seta at level of posterior ocelli. Pair of ocellar setae proclinate and moderately developed. Facial ridge with tiny setulae on lower 2/5. Antenna inserted above the upper margin of eye and at the same level of ocelli. Pedicel reduced, much shorter than scape, with short but stout setulae; postpedicel trilobed, anterior branch bearing stout arista at the tip, and median and posterior branches deriving from a common base; postpedicel notably elongate, its length longer than head height. Lower facial margin moderately warped forwards. Vibrissa moderate, inserted at level of lower facial margin. Oral cavity reduced (narrow) and deep ( Fig. 1 ), so that proboscis and palpus are not exposed and visible as in other tachinids. Palpus, if present, not visible. Proboscis not entirely visible, but retractile and apparently short. Antennal axis slightly shorter than oral axis, giving the head a flat appearance. Gena high.

Thorax ( Figs 1, 3 ): Acrostichal setae 2+3, presutural setae weak. Dorsocentral setae 2+3. Posthumeral seta 1, aligned with intra-alar row. Presutural seta 1, aligned with supra-alar row. Postpronotal setae 2. Notopleural setae 2. Intra-alar setae 0+2; intra-postalar seta absent. Postsutural supra-alar seta 1, no prealar seta. Prosternum bare, narrow and flat. Proepisternum bare. Proepisternal and proepimeral setae short and directed upward. Six anepisternal setae, with some few tiny setulae upcurved at upper anterior corner. Katepisternal setae 2+1, upper setae longer than lower seta. Katepimeron bare. Scutellum with one basal, one lateral, one subapical (parallel to each other), and one discal pairs of setae. Wing ( Fig. 1 ): Costal spine undeveloped; base of R4+5 setulose dorsally and ventrally; M vein bent forward to R4+5 without angle (rounded) and ending at wing margin; anal vein not reaching wing margin. Legs: Fore tibia with row of anterodorsal setae and two posterior setae. Mid tibia with one submedian anterodorsal, two short posterodorsal, two posterior and one submedian ventral seta. Hind tibia with four anterodorsal setae, the two basalmost weaker; three posterodorsal setae and two anteroventral setae.

Abdomen ( Fig. 1 ): Syntergite 1+2 with weak lateral marginal setae, excavation not reaching posterior margin. Tergite 3 with one median marginal, one discal and one lateral marginal pair of setae. Tergite 4 with a marginal row of setae and one discal pair of setae. Tergite 5 with discal and marginal rows. Terminalia: Specimen not dissected.

Type-material examined. Paralectotype male (USNM) labeled “ Formosa / Sauter”; “Mt. Hoozan / 1910.V.”; “Townsend / Genotype / Collection”; “ Type ” [red label]; “ Trischidocera / sauteri / Villen.” [handwritten]; “ SYNTYPE [male symbol] / Trischidocera / sauteri / Villeneuve, 1915: 94 / labeled 1991 NEW”.

Remarks. Villeneuve (1915: 94) did not designate a holotype from among the three males in the type series, and the subsequent treatment of a syntype as “Ht” [holotype] by Townsend (1932: 57) is accepted as a lectotype fixation (see discussion in O’Hara et al. 2009: 10).

With regard to the type-specimens location, Villeneuve (1915: 94) listed his three male syntypes as deposited at Budapest (HNHM). Then, Townsend (1932: 57) examined the “Male Ht” [lectotype] of T. sauteri but cited the depository as “Berlin-Dahlem” [now SDEI]. Later, Townsend (1939: 357) cited Budapest as the “Ht male” [lectotype] location, with “Pts male” in “Rambouillet and Washington”. Townsend (1932) apparently erred in citing the “Male Ht” as deposited in Senckenberg collection because the type catalogue by Rohlfien & Ewald (1974) lists instead three other “ sauteri ” in Tachinidae ( Metopomintho sauteri Townsend, 1927 , Chaetanicia sauteri Townsend, 1932 , and one later species, Trichoformosomyia sauteri Baranoff, 1934 ). Perhaps, Townsend (1932) confused the location of Trischidocera sauteri with one of the other “ sauteri ” deposited at SDEI. The mention of “Ht male ... location, Budapest” by Townsend (1939: 357) is interpreted as a correction to the depository cited in Townsend’s earlier work.

In HNHM, all Tachinidae types (and most of the Diptera collection) formerly deposited in the collection were destroyed in 1956 when Budapest was under attack from Soviet troops ( Boros 1957, Földvári & Papp 2007). The paralectotype mentioned to be in Rambouillet [Villeneuve’s residence] may be anywhere, in France, back to Budapest, etc. Therefore, the information available is that the last remaining paralectotype is the one deposited in the USNM and studied herein.

The holotype female and paratype male of Orectocerina atratula Malloch were kindly photographed by Nigel Wyatt (BMNH). The female has a simple postpedicel, not trilobed as in male, although equally elongate and slender and bearing a terminal arista. All features observed are similar to those of T. sauteri and, based on that, I confirm and keep them as conspecific.

Distribution ( Fig. 8 ). Taiwan and Malaysia.

Figures

FIGURE 8. Geographical distribution of the genus Trischidocera (circles: T. sauteri; squares: T. yunnanensis) [empty symbols denote unexact locality records, where the country or province capitals were used to plot the occurrence].

FIGURES 1 – 3. Trischidocera sauteri Villeneuve, paralectotype male. 1. Lateral habitus. 2. Head, frontal view. 3. Head, lateral view, and thorax, dorsal view. (Scale bars 1 mm.)