Chrysotus plumarista Runyon & Capellari, 2018

Runyon, Justin B. & Capellari, Renato S., 2018, Palpi aplenty: new species in the Chrysotus longipalpus species group (Diptera: Dolichopodidae), Zootaxa 4399 (4), pp. 579-585 : 583-584

Chrysotus plumarista Runyon & Capellari , sp. nov.

( Fig. 1 )

Description. Male. Body length, 1.6–1.7 mm. Wing length, 1.4 mm, width, 0.5 mm. Head. Frons dark brown to black, with violet reflections; antenna mostly brown, arista-like stylus ( Fig. 1 , inset) with distal fifth very slightly broadened, feathered and white at apex; face yellow, essentially obliterated by eyes near middle; proboscis yellowbrown with pale setae; palpus ( Fig. 1 ) white, shiny, bare except small medioapical seta, roundish with inner and apical edge nearly straight, apical edge minutely fringed (ratio tibia I: palpus, 23:12) (MSSC). Thorax. Mesonotum and scutellum metallic green with violet reflections; mesopleuron brown with some bluish reflections and some pruinosity. Wing. Halter yellow, calypter brownish. Legs. I: 22, 23, 12, 5, 4, 2, 2. II: 25, 28, 14, 6, 4, 3, 2. III: 29, 32, 8, 8, 5, 3, 2. Legs yellow except all coxae and base of femur I brown; apical tarsomeres only very slightly darkened. Setae on coxae I, II, and III brown. Hypopygium brown, not dissected; cercus yellow, short, with some brown hairs. Female. Unknown.

Etymology. Name derived from the Latin pluma (feathery) + arista, in reference to the slightly broadened and feathered apex of the arista in males ( Fig. 1 ).

Type material. HOLOTYPE ♂, “ALABAMA: Baldwin Co. | Byrnes (Byrnes Lake) | 30°79’N 87°91’W | 18 July 2000 | J.W. McCreadie”, “HOLOTYPE | ♂ Chrysotus | plumarista | Runyon & Capellari 2018 [red label]” (USNM, type number USNMENT01447155). Paratype: Alabama: Mobile Co., Chunchula, malaise, 30.90°N, 88.20°W (site 20), 19 April 2004, E. Benton (1 ♂, USNM).

Distribution. USA: Alabama, Mobile-Tensaw River Delta.

Remarks. This is the only known species in the C. longipalpus group with a modified arista ( Fig. 1 , inset). The antennae are missing in the paratype.

Figures

FIGURES 1–4. Heads of males of new species in the Chrysotus longipalpus species group. 1. Chrysotus plumarista sp. nov., dorsolateral view; inset shows male arista. 2. Chrysotus mystax sp. nov., anterior view. 3. Chrysotus mccreadiei sp. nov., anterior view.4. Chrysotus keyensis sp.nov.; a. anterodorsal view; b. lateral view. Scale bar = 0.5 mm.