Ampsalis geniata Walker

Winterton, Shaun L., 2023, Wasp-mimicking soldier flies of the Australian Region: revision of Ampsalis Walker, Elissoma White and Lagenosoma Brauer (Stratiomyidae: Clitellariinae), Zootaxa 5246 (1), pp. 1-63 : 13-14

Ampsalis geniata Walker

( Figs 8 ; 20 ; 35 )

Ampsalis geniata Walker 1859: 99 — Brunetti, 1923: 110 [redescription]; James, 1975a: 29 [catalogue]; Lindner, 1935: 46 [faunistic record]; Woodley, 2001: 153 [catalogue].

Diagnosis. Wing smoky infuscate in distal third, pterostigma yellowish; head and thorax dark yellow, suffused with brown; scutum dark yellow with brown suffusion darker posterior to transverse suture, pale yellow along dorsocentral stripes; scutellum brown with darker margin and medium sized spines; abdominal tergites 2–5 with broad yellow margin; legs yellow.

Redescription. Body length = ca. 13.5 mm. Head. Female frons slightly rounded, yellow, female with paired elongate brown suffusion laterally, extending dorsally flanking ocellar tubercle; face strongly rounded, yellow, with short, dark setal pile; parafacial yellow; ocellar tubercle black; yellow postocular ridge, overlain with sparse, short dark setae; occiput slightly rounded to flat medially, yellow; antenna (length = 5.0 mm) with scape yellow, pedicel dark yellow with black setae, flagellomeres I–V dark yellow, flagellomeres VI–VIII black, flagellomeres IV–VII equal length of flagellomere I, ratio of length of flagellomere VII to VIII is 1:29, flagellomere VIII elongate and deeply plumose with microtrichia. Thorax. Dark yellow with brown-black markings on scutum, single medial stripe and incomplete stripes anterior to transverse suture, mostly solid dark posterior of transverse suture; pleuron dark brownish suffusion, darker ventrally; scutellum reddish brown with darker margin, scutellar spines well developed, equal to 1/4 of scutellum length; coxae yellow to brown, legs yellow, foretibia light yellow; haltere brownish yellow; wing hyaline, dark suffusion in apical third venation brown; pterostigma yellow. Abdomen. Female abdomen ovoid, yellow, tergite 1 black, tergites 2–5 with broad, black-brown medial stripe. Genitalia. Apparently broken and lost.

Comments. Brunetti (1923) suggested that A. geniata may be conspecific with A. iterabilis , but the body and leg colouration, as well as differences in antennal length and colouration described by Walker (1859: pp. 98–99) are sufficiently different to consider them as separate species. Interestingly, the type series was collected by the noted naturalist, Alfred Russell Wallace sometime between 1854 and 1859 during his travels through the ‘Malay Archipelago’, presumably during his stay in the countryside outside of Makassar ( Wallace 1869). Brunetti (1923) described the variation between the syntypes, one being headless and noticeably darker than the other. This redescription is based on the paler female syntype ( Fig. 8 ), which is herein designated as the lectotype to stabilise the species concept. Lindner (1935) discussed a male specimen he identified as A. geniata , matching the redescription of the species by Brunetti (1923). This male specimen was collected by Gerd Heinrich from Talassa (Maros), a township very close to the type locality, but the specimen is now lost (Hauser pers. comm.) so its identity cannot be confirmed. Ampsalis geniata is distinguished from other species of Ampsalis by the wing being pale smoky infuscate in the distal third only, antennae darker distally and longer than the head is wide, and all femora are yellow. Importantly, antennal length appears to differ markedly between A. geniata and A. iterabilis , although only the female lectotype has the antennae still present, and the remaining specimens of both species do not. Therefore, we must rely on the original description by Walker (1859) regarding the antennal length of A. iterabilis . The male is unknown for this species.

Type material— Lectotype, 1 female, INDONESIA: Sulawesi: ‘ Makassar’ Ujung Pandang [-5.1562, 119.4184], A. R. Wallace ( NHMUK) [examined].

Figures

FIGURE 8. Ampsalis geniata Walker. A. Female lectotype, lateral view; B. same, dorsal view (images by Martin Hauser with permission of The Natural History Museum, London).

FIGURE 20. Stylised illustrations of the antenna of Eudmeta, Ampsalis, Elissoma and Lagenosoma.

FIGURE 35. Distribution of Australasian Ampsalis species.