Chaetotheresia crassa ( Wiedemann, 1830 )

de Santis, Marcelo Domingos & de V. P. Dios, Rodrigo, 2023, Monotypic no more: revision and an additional species for the genus Chaetotheresia Townsend, 1931 (Diptera: Tachinidae), Journal of Natural History 57 (5 - 8), pp. 285-298 : 290-292

Chaetotheresia crassa ( Wiedemann, 1830)

( Figures 1 , 3–4 )

Musca crassa Wiedemann, 1830: 387 . Type locality: Brazil. According to Townsend (1931a, 1931b), a male holotype is deposited in ZMHU and a paratype male is deposited in NHMW, but see the note below.

Chaetotheresia crassa Townsend 1931a: 346 (erection of the new genus Chaetothereisa for Musca crassa ); Townsend 1931b: 102 (notes about type depository of C. crassa ); Guimarães 1971: 36 (catalogue); O̍ Hara and Henderson 2020a: 36 (checklist of World Tachinidae ).

Myiomima brasiliana Brauer and Bergstamm, 1891: 60 (1891: 364) . Female holotype, not examined (NHMW). Type locality: Brazil. Townsend 1931a: 347 (synonymy of C. crassa with M. brasiliana ); Townsend 1931b: 102 (notes about type depository of M. brasiliana ); Guimarães 1971: 36 (catalogue, confirmation of the synonymy established by Townsend).

Note

Musca crassa Wiedemann, 1830 was described from an unspecified number of specimens from Brazil and without sex determination. The depository for these specimens was given as ′Im Berliner Museum̍ and ′In meiner Sammlung̍. The first is the Museum für Naturkunde Berlin (ZMHU), while the second refers to the personal collection of Christian R. W. Wiedemann (1770–1840). According to Pont (1996, 148):Some time before his [Wiedemann̍s] death, he sold his insect collection to Wilhelm von Winthem of Hamburg, and in 1852 von Winthem̍s entire collection was purchased by Vienna̍s k. k. Hofmuseum (the present Natural History Museum, Vienna). Wiedemann̍s collection was still kept separate as late as 1880 (Brauer 1880, 106), but sometime after this was combined with the von Winthem and other collections of Vienna Natural History Museum to form a single Diptera collection. The specimens have a printed label ′det. Wiedemann̍ or ′coll. Wiedemann̍, with the species-name usually added.

The type material from Berlin and NMHW was studied by Townsend (1931b). In a brief note, Townsend (1931, 102) wrote that there is a male holotype at ZMHU and a male paratype at NHMW. However , this potential holotype was not found in the ZMHU Diptera collection (Jenny Pohl, personal communication). On the other hand, type material of C . crassa could be found at NHMW, and – differently from what was written by Townsend (1931b, 102) – there are two conspecific males deposited at the museum ( Figure 5 ) and an additional male that is not conspecific ( Figure 6 ) and probably represents a new or closely related genus.

The two male syntypes in NHMW that are conspecific, and in good condition, are labelled as follows:

(1) ′crassa/ Coll . Wiedem ̍. [′crassa̍ handwritten]; ′crassa w/ Brazil./ Mus. Berol̍.; ′ M. crassa J/ Brasil ̍.; ′ Syntype / Musca / crassa/ examined 1999/ P. Sehnal̍ [′ Musca crassa ̍ handwritten]; ′(1)/ Typenk at./ P. Sehnal 1999̍.

(2) ′ Brasilien ̍; ′ crassa Wd. / Coll. Winthem̍ [′ crassa Wd. ̍ handwritten]; ′ crassa Wied / Brasilia̍ [handwritten]; ′ Syntype / Musca / crassa/ examined 1999/ P. Sehnal̍ [′ Musca crassa ̍ handwritten]; ′(3)/ Typenk at./ P. Sehnal 1999̍.

Syntype 1 ( Figure 5 ) referred to above presents a label reading ′ Mus . Berol ̍ that according to Pont (1996) refers to the Royal Museum of Berlin, currently the ZMHU . Thus, it seems that this syntype could be the one mentioned by Townsend (1931) that was in Berlin ( ZMHU) . However, as there is no label that links this specimen to Townsend, it is not clear whether this is the same one examined by him. In the interest of nomenclatural stability and to restrict the name to a single specimen, the male with ′ Mus . Berol̍ label is hereby designated as lectotype of Musca crassa Wiedemann, 1830 .

The current combination for this species is Chaetotheresia crassa (1830) .

Figures

Figure 1. Chaetotheresia crassa (Wiedemann, 1830). (A) J, dorsal habitus. (B) J, lateral habitus. (C) ♀, dorsal habitus. (D) ♀, lateral habitus.

Figure 3. Chaetotheresia crassa (Wiedemann, 1830), J terminalia. (A) Fifth sternite, posterior view. (B) Lateral view (Hy: hypandrium; Po: postgonite; Pr: pregonite). (C) Posterior view (C: cercus; E: epandrium; S: surtylus). (D) Lateral view (Bs: bacilliform sclerite; C: cercus; E: epandrium; S: surtylus). Scale bar: 0.1 mm.

Figure 4. Chaetotheresia crassa (Wiedemann, 1830), ♀ terminalia. (A) Posterior view (6 T: sixth tergite; 7 T: seventh tergite; 8S: eighth sternite; C: cercus). (B) Spermatheca, only a single one represented. Scale bar: 0.1 mm.

Figure 5. Lectotype of Musca crassa Wiedemann, 1830, J. (A) Dorsal habitus. (B) Lateral habitus. (C) Syntype labels.

Figure 6. One of the syntypes of Musca crassa Wiedemann, 1830, J, that is not conspecific with C. crassa. (A) Dorsal habitus. (B) Lateral habitus. (C) Syntype labels.