Paramixogaster sulawesiana Reemer, 2024

Reemer, Menno & Sankararaman, Hariharakrishnan, 2024, Revision of the Oriental species of the hoverfly genus Paramixogaster Brunetti, 1923 (Diptera, Syrphidae, Microdontinae), ZooKeys 1208, pp. 1-48 : 1-48

Paramixogaster sulawesiana Reemer sp. nov.

Figs 12 , 102–108 , 134

Type material.

Holotype. Indonesia • 1 ♂; Sulawesi, Rantepao ; July 1936; leg. L. J. toxopeus; coll. RMNH. Label 1: “ C. [handwritten, printed letters SW are crossed out] Celebes // VII // Rantepao. // L. J. Toxopeus 1936 ”; label 2: “ Paramixogaster // sp. n. // Det. M. Reemer 2021 // Specimen MR 1392 ”; label 3 (red): “ HOLOTYPE // Paramixogaster // sulawesiana // Reemer 2024 ”.

Paratypes. Indonesia • 1 ♂ 1 ♀; Sulawesi, coll. USNM. [specimen labels only state “ Macassar ”; [unique specimen identifiers USNMENT 01541879 and USNMENT 01541880 for male and female, respectively].

Diagnosis.

Body length: 8–9.5 mm. Belongs to the group of species with lateral bulges on the frons (Figs 104 , 105 , 107 ). From P. fujianensis it differs by tergite 2 being less than twice as long as wide (more than twice as long as wide in P. fujianensis ). From P. icariiformis it differs by the presence of fasciae of golden setulae along the posterior margins of tergites 3 and 4 (absent in P. icariiformis ). There is a continuous fascia of golden setulae along the transverse suture of the scutum, and there are fasciae of golden setulae along the posterior margins of tergites 3 and 4 (Fig. 102 ). These fasciae are not as dense and as sharply demarcated as in P. kodaiana Sankararaman & Reemer , sp. nov. (from which it also differs by the lack of dark colouration in wing cell r 4 + 5), but more similar to those in P. huoi Reemer , nom. nov. From the latter species, P. sulawesiana Reemer , sp. nov. differs by the wing venation: the apex of R 2 + 3 is situated well beyond the joint of M 1 with R 4 + 5 (at approximately the same level in P. huoi Reemer , nom. nov.). Male genitalia as in Fig. 134 .

Description

(based on holotype). Adult male. Body length: 9 mm.

Head. Face occupying ~ 1 / 2 of head width in frontal view, with sides somewhat converging ventrad; blackish brown with widely yellow lateral and ventral margins; entirely golden yellow setulose. Gena yellow, yellow setulose. Oral margin not notched anteriorly, laterally weakly produced. Frons posteriorly with shining blackish pair of lateral bulges which are short black setulose, except golden yellow setulose on a triangular patch adjacent to eye margin, these bulges are separated by a narrow yellowish crease; frons anteriorly (laterad of antennal fossa) with pair of more or less flat yellow areas which are golden yellow setulose, separated from face by pair of shiny black bare maculae. Vertex swollen, with oblique depressions converging anteriad; blackish brown; short black setulose except golden yellow setulose along all margins. Occiput black; golden yellow setulose dorsally, white setulose ventrally. Eye bare. Antennal fossa approximately as high as wide. Antenna orange-brown; postpedicel 6.5 × as long as scape. Arista ~ 2 × as long as scape.

Thorax. Mesoscutum blackish brown; short black setulose, except for narrow fascia of golden yellow setulae along transverse suture, large patch of golden yellow setulae anterior to scutellum, and small patch of golden yellow setulae anterior to postalar callus. Postpronotum brown, bare. Postalar callus yellow, golden yellow setulose. Scutellum without calcars; yellow; golden yellow setulose. Pleura yellowish dorsally, brown ventrally. Anepisternum and anepimeron entirely covered with thick golden yellow setulae, appressed and directed hindward. Katepisternum long golden yellow setulose dorsally; bare ventrally. Katepimeron with a few long yellow setulae. Katatergite and anatergite short microtrichose. Metanotum shining brown. Calypter and halter yellow.

Wing: hyaline; microtrichose, except bare in cell r 1 narrowly along Rs, narrowly along veins in basal 1 / 3 of r 4 + 5, entirely on cell br (except for microtrichia along vena spuria), narrowly along veins in antero-basal 1 / 5 of cell dm, entirely on cell bm, basal 2 / 3 of cell cup.

Legs: yellowish brown, except hind femur darker brown.

Abdomen. Constricted basally, narrowest at basal 1 / 6 of tergite 2, widest at transition between tergites 3 and 4. Tergite 1 dark brown; yellowish setulose. Tergite 2 dark brown with two large, elongate, pale yellow maculae from anterior margin to ~ 3 / 5 of tergite, and yellow fascia of ~ 1 / 6 of tergal length along posterior margin; short black setulose, except bare on yellow maculae with fascia of thick golden yellow setulae along posterior margin. Tergite 3 dark brown, except yellowish brown fascia of ~ 1 / 5 of tergal length along posterior margin; black setulose anteriorly, golden yellow setulose posteriorly. Tergite 4 dark brown except widely yellow along posterior and lateral margins; short black setulose antero-medially, golden yellow setulose postero-medially and laterally. Sternite 1 brown; sparsely short black setulose. Sternite 2 yellow; bare. Sternites 3 and 4 brown; yellow setulose. Genitalia as in Fig. 134 .

Notes.

The male paratype differs from the holotype in the following aspects: body length 8.5 mm; postpedicel 8 × as long as scape; vertex golden yellow setulose; dark parts on head, thorax, and abdomen more brownish (rather than blackish as in holotype). The female paratype (in which the antennae are missing) differs from the male holotype in the same aspects of colouration, as well in the body length of 9 mm. The colour differences between holotype and paratype are considered to either represent intraspecific variation or result from differences in preservation history.

Distribution.

Only known from Sulawesi ( Indonesia).

Etymology.

The specific epithet (adjective) refers to the type locality.

Figures

Figures 11, 12. Position of apex of vein R 2 + 3: 11 at approximately same level as joint M 1 with R 4 + 5 (Paramixogaster huoi Reemer, nom. nov. holotype) 12 more distal than joint of M 1 with R 4 + 5 (P. sulawesiana Reemer, sp. nov. holotype).

Figures 102–108. Paramixogaster sulawesiana sp. nov. male, holotype: 102 habitus, dorsal 103 habitus, lateral 104 head, lateral 105 head, frontal 106 wing 107 head, dorsal 108 antenna.

Figures 130–137. Male genitalia of Paramixogaster species: 130 P. contracta (paratype Microdon subpetiolatus Thompson) 131 P. halmaherensis Reemer, sp. nov. holotype 132 P. luxor holotype 133 P. sacki Taiwan, RMNH 134 P. sulawesiana Reemer, sp. nov. holotype 135 P. jubata Reemer, sp. nov. paratype Vietnam 136 P. indica (paratype P. wegneri Keiser syn. nov.) 137 P. vespiformis Sumatra, RMNH.