Chrysotus propinquus (BECKER) Capellari & Amorim, 2014

Capellari, Renato Soares & Amorim, Dalton De Souza, 2014, New combinations and synonymies for Neotropical species of Diaphorinae (Diptera: Dolichopodidae), Beiträge Zur Entomologie = Contributions to Entomology 64 (2), pp. 375-381 : 377-378

Chrysotus propinquus (BECKER) , comb. n.

Diaphorus propinquus BECKER, 1922: 171

Examined material: LECTOTYPE , hereby designated, “Peru-Meshagua | 13.X.03 | Urubambafl.” [dark green label]; “ Diaphorus | propinquus B | det. Becker” [white label]; “” [sic, white label]; “Typus | Diaphorus | propinquus  | Beck. ” [red label]; “ propinquus | Beck. ” [white label]; “ SYNTYPUS | des. U. Kallweit | 1993” [orange label]; “ Chrysotus | propinquus | (Becker) LECTOTYPE | Capellari & Amorim 2014” [red label]. PARALECTO- TYPES (all labeled as “ Chrysotus | propinquus | (Becker) PARALECTOTYPE | Capellari & Amorim 2014” [yellow label]): , “Peru-Rosalina | 20.8.03 | Urubambafl.” [dark green label]; “ Diaphorus | propinquus Beck | det. Becker” [white label]; “” [white label]; “Typus [sic] | Diaphorus | propinquus  | Beck ” [red label]. , “Peru-Rosalina | 19.8.03 | Urubambafl.” [dark green label]; “ Paratypus | Diaphorus | propinquus Beck ” [red label]. , “Peru- Meshagua | 1.X.03 | Urubambafl.” [dark green label]; “ Paratypus | Diaphorus | propinquus | Beck ” [red label].

Remarks: CAPELLARI and AMORIM (2010) suspected this species and Chrysotus mediotinctus , comb. n. could be synonyms of C. maculatus (PARENT) . Examination of the types revealed main differences only in some aspects of the color pattern. C. mediotinctus , comb. n. has a darker and uninterrupted brown stripe on the wing membrane, coxa III brown, and metepimere concolorous with the pleura. C. propinquus , comb. n. is very similar to C. mediotincutus , comb. n., but has the stripe on wing membrane lighter, and the coxa III is yellowish. C. maculatus has yellow coxa III and metepimere, while the brown stripe on wing membrane is narrower than in C. mediotinctus , comb. n., interrupted between R 4+5 and M 1 (not figured in PARENT 1934: pl. 68, fig. 14). It is possible that all those characters can vary as a result of different degrees of melanization in a single species. We preferred, however, to keep all species as separate taxa until further evidence is available to take a more robust decision concerning a synonymy.

Key to the species of the mediotinctus -group of Chrysotus (males)

1. Wing membrane hyaline .................................................................................................................................................... 2

1'. Wing membrane with distinct brown spot ...................................................................................................................... 3

2. Coxa III and metepimere yellow ............................................................................... C. luteipalpus (PARENT) , comb. n.

2'. Coxa III and metepimere brown ..................................................................................................... C. singularis PARENT

3. Spot on wing membrane interrupted at level between R 4+5 and M 1 ( CAPELLARI & AMORIM 2010: fig. 19) .............. .......................................................................................................................................................... C. maculatus (PARENT)

3'. Spot on wing membrane uninterrupted (cf. BECKER 1922: fig. 63). ............................................................................ 4

4. Spot on wing membrane dark brown; coxa III brown ....................................... C. mediotinctus (BECKER) , comb. n.

4'. Spot on wing membrane light brown; coxa III yellow, brownish at base ........... C. propinquus (BECKER) , comb. n.