Allometopon giallo, Owen Lonsdale, 2016

Owen Lonsdale, 2016, Revision of the genus Allometopon Kertész (Diptera: Clusiidae), Zootaxa 4106 (1), pp. 1-127 : 28-29

publication ID	https://doi.org/ 10.11646/zootaxa.4106.1.1
publication LSID	lsid:zoobank.org:pub:A5ADF236-5219-4014-9DC4-C43F981DD1A4
DOI	https://doi.org/10.5281/zenodo.3503587
persistent identifier	https://treatment.plazi.org/id/6866497B-F10C-3468-FF39-A0A1F531FCF3
treatment provided by	Plazi
scientific name	Allometopon giallo
status	sp. nov.

Treatment

Allometopon giallo View in CoL spec. nov.

Figs 80–84 View FIGURES 80 – 84

Description. General: ( Figs 80, 81 View FIGURES 80 – 84 ) Body length 3.9mm. Arista short plumose. M1+2 ratio 3.5. First flagellomere not much enlarged, slightly extended along dorsal and ventral margins. Female unknown.

Chaetotaxy: Three fronto-orbital setae, slightly decreasing in length anteriorly. Ocellar seta (damaged) apparently slightly larger than ocellar tubercle. Postvertical seta (damaged) thin, as long as ocellar tubercle. Interfrontal seta barely distinguishable from surrounding scattered setulae on frons. First flagellomere along distal margin with hairs as long as width of base of arista. Anterior dorsocentral half length of posterior seta; closely set posteriorly. Acrostichal seta well-developed. One well-developed lateral scutellar seta.

Colour: Setae yellow. Frons yellow with ocellar tubercle dark brown; pedicel and scape light yellow, first flagellomere and base of arista white; back of head yellow, white below foramen, dorsally with one pair of dark brown stripes radiating from foramen that barely extend onto posterior margin of frons; remainder of head below frons yellowish-white; parafacial, gena and postgena silvery tomentose. Scutum yellow in ground colour; anterior half of postpronotum and anterior margin of scutum dark brown; supra-alar region light yellow; one pair of short dark brown intra-alar stripes connected medially by irregular brown to light brown patch that is dark brown around base of acrostichal setae. Scutellum brown dorsally, margin with irregular yellow mottling. Mediotergite dark brown, yellow laterally; anatergite light brown; katatergite dark brown. Pleuron and legs yellowish-white with large dark brown spot in posterodorsal corner of anepisternum. Wing infuscated on distal half around veins R2+3 to M1, with pigment darker towards costa. Halter white. Tergite1 light yellow; tergites 2–6, sternite 8 and epandrium dark brown, with lateral margin and anterolateral region of epandrium yellow; surstylus and cercus light yellow to white.

Male terminalia: ( Figs 82–84 View FIGURES 80 – 84 ) Surstylus slightly higher than epandrium, posterobasal margin raised as shallow, slightly incurved lobe, apical 1/3 curved anteriorly and with tubercle-like setae along inner-distal margin. Hypandrial arm narrowed at base; lobe as wide as long and with two short posterodorsal setae. Phallapodeme rodlike. Pregonite long, membranous, widened to meet distal margin of hypandrium, with series of five short setae along dorsal margin. Postgonite short with several long apical setae. Basiphallus well-developed. Epiphallus short, weakly sclerotized. Distiphallus nearly half length of phallapodeme, narrow, minutely textured. Paraphallus slightly longer than distiphallus, weakly sclerotized and minutely spinulose along dorsum past base.

Etymology: The specific epithet is Italian for “yellow”, in reference to the base colour of the species, and is treated as a noun in apposition.

Distribution: Vietnam.

Holotype: VIETNAM. Vinh Phue Province: Tamado National Park, Pham Hong Thai, x/ xi.2011, Malaise trap (1♂, CSCA).

Comments: Allometopon atromaculatum ( Fig. 291 View FIGURES 291 – 297. 291 – 292 ), A. giallo and A. grypostylis ( Fig. 90 View FIGURES 90 – 94 ) are likely sisterspecies related to A. geniculatum ( Fig. 74 View FIGURES 74 – 79 ) and A. lux ( Fig. 143 View FIGURES 143 – 147 ), differing in having a bent apex of the surstylus that is rounded (not sharply angled), a broad, triangular and setose hypandrial lobe, a large, posterodorsally setose pregonite and a mixed yellow and brown scutellum. Allometopon giallo differs in having one pair of short dark brown postsutural stripes with a brownish intervening region (not a longer single medial stripe with one pair of narrow lateral offshoots), the back of the head has one pair of stripes (not medially fused), the scutellum is only mottled yellow laterally, the surstylus is more shallowly curved, and the postgonite is longer and smooth ( A. grypostylis has additional spinules clustered around the setae; Fig. 94 View FIGURES 90 – 94 ).

Allometopon atromaculatum has a dorsally brown scutellum and a gradually curving surstylus, similar to A. giallo , but the base of the surstylus is stouter and sickle-shaped. The pigmented posteromedial region of the scutum is also consolidated into a larger, evenly brown spot. While the head of the A. atromaculatum type is missing, the original description notes that the head is entirely yellow with the frons slightly darker with only two (not three) fronto-orbitals.