Chrysotus longipalpus, Aldrich, 1896

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 : 580

Key to males of the Chrysotus longipalpus species group (modified from Capellari 2015)

1 Eyes nearly contiguous below antennae; antennal postpedicel subtriangular; palpus variously enlarged. First tarsomere I with ventroapical swelling; tibia III with row of anterior to anterodorsal setae; femur III with 2 rows of ventral setae on basal half … Chrysotus longipalpus species group..................................................................... 2

- Not with the above combination of characters................................................other species groups

2 Palpus clearly divided into an enlarged basal part and a strap-like apical projection after abrupt tapering................. 3

- Palpus not clearly divided into two parts................................................................... 7

3 Palpus brownish, thick ( Capellari 2015, fig. 1f); coxa I light brown, yellow at apex, with brownish setae on anterior surface (Belize).......................................................................... C. pachystoma Capellari

- Palpus mostly white or yellowish, thin; coxa I entirely yellow, with whitish to yellow setae on anterior surface............ 4

4 Basal part of palpus densely covered with brownish setae; distal part slightly tapered towards apex, without apical lamella.. 5

- Basal part of palpus covered sparsely with brownish setae; distal part strip-like, with apical lamella.................... 6

5 Palpus with silvery tip ( Capellari 2015, fig. 1a); apical 1/3–1/4 of femur III brown.................. C. coquitos Capellari

- Palpus with brown tip ( Fig. 3 ); femur III entirely yellow...................................... C. mccreadiei sp. nov.

6 Apex of palpus narrowly oblong, slightly pointed and white ( Capellari 2015, fig. 1d)................ C. miripalpus Parent

- Apex of palpus rounded and black ( Figs 4a, b , 5 ).............................................. C. keyensis sp. nov.

7 Palpus entirely bright silvery, relatively short (length ± 2x width) and often truncate apically; nearly bare of hairs or setae (as in Figs 1, 2 )............................................................................................ 8

- Palpus never entirely bright silvery, but often bright yellowish; relatively long (length> 2.5x width), either uniformly narrow or only gradually tapering towards apex; with hairs or setae scattered over much of surface.......................... 10

8 Arista-like stylus slightly broadened, feathered, and white at apex ( Fig. 1 )........................ C. plumarista sp. nov.

- Arista unmodified..................................................................................... 9

9 Palpus oblong ( Capellari 2015, fig. 1b); antenna entirely brown; coxae and pleura brown............ C. crosbyi Van Duzee

- Palpus distinctly truncate apically and pointed laterally ( Fig 2 ); antenna with first flagellomere yellow ventrally; coxae and pleura mostly yellow..................................................................... C. mystax sp. nov.

10 Palpus uniformly narrow and straight..................................................................... 11

- Palpus tapered towards apex............................................................................ 12

11 Antenna brown; palpus brown with silvery tip ( Capellari 2015, fig. 1h); coxa I brown, femur I yellow...................................................................................................... C. zumbadoi Capellari

- Antenna yellow; palpus yellow, bright silvery ( Capellari 2015, fig. 1g); coxa and femur I whitish yellow.................................................................................................. C. xiphostoma Robinson

12 Palpus sub-triangular with rounded apex, entirely yellow ( Capellari 2015, fig. 1c)................ C. longipalpus Aldrich

- Palpus narrow throughout, pointed, basal half yellow with apical half brownish and silvery pruinose ( Capellari 2015, fig. 1e)............................................................................... C. neopedionomus Capellari

Figures

FIGURE 5. Lateral male habitus of the holotype of Chrysotus keyensis sp. nov. Scale bar = 1 mm.

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.