Elissoma White

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 : 17-19

publication ID	https://doi.org/ 10.11646/zootaxa.5246.1.1
publication LSID	lsid:zoobank.org:pub:BDE8C45B-4F03-403D-8D57-4EFC1584BFE8
DOI	https://doi.org/10.5281/zenodo.7675139
persistent identifier	https://treatment.plazi.org/id/726B879C-FF8B-025F-FF56-28EEDAE8FE85
treatment provided by	Plazi
scientific name	Elissoma White
status

Treatment

Elissoma White View in CoL

Elissoma White, 1916: 86 View in CoL — Hardy, 1920: 49 [key, checklist], 1933: 409 [key, revision]; Woodley, 1989: 314 [catalogue], 2001: 166 [catalogue]. Type species: Elissoma lauta White, 1916 View in CoL , by monotypy.

Pycnothorax Kertész, 1923: 124 View in CoL — Woodley, 1989: 315 [catalogue], 2001: 172 [catalogue]. Type species: Pycnothorax australis Kertész, 1923: 125 View in CoL , by original designation. Syn. n.

Diagnosis. One pair of minute to moderately-sized scutellar spines, shorter than scutellum length; notopleural spine absent; wing vein M 3 present or absent; M 4 arising on discal cell, cross-vein r–m present; wing straight, not bent over abdomen; face flat to broadly rounded, without nose-like process; male eyes contiguous medially below ocellar tubercle; eye not pilose; postocular ridge broadly carinate in female, male narrow to broadly carinate; antenna greatly elongate, scape much shorter than flagellum; flagellum cylindrical, circular sensory pits on flagellomeres I–III, flagellomeres IV–V very short and of similar length; flagellomere VIII longer than all other flagellomeres combined, covered with deeply plumose microtrichia or more sparse larger setae, sometimes white apically; abdomen narrowed basally, ovoid to strongly petiolate, frequently strongly sexually dimorphic.

Included species. Elissoma australis ( Kertész, 1923) comb. n.; E. brunnea Hardy, 1933 ; E. gilva sp. n.; E. danielsi sp. n.; E. hauseri sp. n.; E. ichneumonoides sp. n.; E. hespera sp. n.; E. lauta White, 1916 ; E. minuta sp. n. and E. scapula sp. n.

Comments. Hardy (1933) noted that Elissoma and Pycnothorax were very similar and belonged to the same group of genera, even suggesting that they may be congeneric. He discussed that the generic distinctions amongst these genera are poor and went on to state that: “…variations of this nature cannot be accepted as of generic importance and it becomes very evident as more species accumulate, that the genera will need to be erected on better grounds than has been done in the past.” ( Hardy 1933: p. 410).

White (1916) did not list the gender of Elissoma in his original description and the etymology of the genus is unclear, although the species epithet of the type species is feminine. In contrast to all previous authors, Woodley (1989) used the neutral form of the combinations of E. lautum and E. brunneum , and then the original feminine form in Woodley (2001); the feminine form for Elissoma is likewise used here. Most Elissoma species are found in the eastern Australian states of New South Wales, Victoria and Queensland, with the bulk of species found in coastal Queensland. Two species are known from Western Australia. Elissoma is very similar to Ampsalis but is differentiated by a rounded or flat face, lacking the ‘nose’-like process of the latter. The scutellar spines are general very small to minute; when present in other genera they are larger. The only other clitellariine genera in the Oriental and Australian regions with scutellar spines (and lacking notopleural spines) are Campeprosopa and Ampsalis . Antennal length is extremely variable in this genus (ranging from 1.5 mm in E. minuta sp. n. to 8.5 mm in E. ichneumonoides sp. n.), but proportions of flagellomeres remain relatively constant; these proportions are typically not found in other Clitellariinae genera aside from Ampsalis and some Lagenosoma .

Key to Elissoma species

1. Wing vein M 3 absent ( Fig. 21A View FIGURE 21 )........................................................................ 2.

- Wing vein M 3 present ( Fig. 21B–D View FIGURE 21 )..................................................................... 3.

2. Body predominantly orange with black markings ( Fig. 32C View FIGURE 32 ); antennae yellow basally; foretarsi white; wing with smoky infuscation medially ( Figs 11C, D View FIGURE 11 ; 21A View FIGURE 21 ) (Queensland)............................................. E. brunnea Hardy. View in CoL

- Body predominantly black with dark yellow line dorsally along anepisternum and laterally on abdomen ( Figs 13E View FIGURE 13 ; 32E View FIGURE 32 ); antennae entirely black; foretarsi black; wing hyaline ( Fig. 13F View FIGURE 13 ) (Western Australia)....................... E. minuta sp. n.

3. Wing largely uniform dark infuscate; scutum tri-coloured, anteriorly dark yellow (orange in living specimen), black in middle section and white (pink in living specimen) posteriorly, concolourous with scutellum ( Figs 2 View FIGURE 2 ; 13C, D View FIGURE 13 ) (Victoria, New South Wales)................................................................................. E. lauta White. View in CoL

- Wing hyaline; scutum and scutellum otherwise coloured..................................................... 4.

4. Antennae completely dark; setae present along flagellomeres V–VIII; male postocular ridge raised and angular ( Figs 25J View FIGURE 25 ; 26A, B View FIGURE 26 )................................................................................................ 5.

- Antennae dark with distal flagellomeres white ( Fig. 25E–I View FIGURE 25 ) (completely black in E. hauseri sp. n. ( Fig. 27K View FIGURE 27 ); setae absent on flagellum; male postocular ridge not raised and angular...................................................... 6.

5. Scutum yellow with dark brown markings ( Fig. 12E–H View FIGURE 12 ); abdomen yellow with brown markings ( Fig. 32G View FIGURE 32 ); scutellar spines minute ( Fig. 28G View FIGURE 28 ) (Queensland)............................................................ E. hespera sp. n.

- Scutum orange with black punctate markings indicating setal bases, pitch black anteriorly and anterolaterally ( Fig. 13G, H View FIGURE 13 ); scutellar spines well developed ( Fig. 29A View FIGURE 29 ) (Western Australia).................................... E. scapula sp. n.

6. Pleuron predominantly black, narrowly yellow around base of wing ( Fig. 13A View FIGURE 13 ); antennae very long (ca. 5x head length) ( Fig. 25I View FIGURE 25 ); scutellar spines at least half the length of scutellum ( Fig. 28I View FIGURE 28 ) (Queensland).............. E. ichneumonoides sp. n.

- Pleuron predominantly pale (orange, yellow or white) with portions of some sclerites black; antenna length at most 4x head length; scutellar spines less than half the length of scutellum................................................... 7.

7. Scutellum orange-brown with cream-white margin ( Fig. 28E View FIGURE 28 ); anepisternum with dark brow spot dorsally; hind tibia with dark brown band ( Fig. 12A–D View FIGURE 12 ) (Queensland)...................................................... E. danielsi sp. n.

- Scutellum otherwise coloured; anepisternum black anteriorly, white to yellowish green posteriorly (sometimes also dorsally); hind tibia entirely yellow or brownish black................................................................ 8.

8. Scutellum orange ( Fig. 28F View FIGURE 28 ); hind tibia dark yellow ( Fig.11E, F View FIGURE 11 ) (New South Wales).................... E. gilva sp. n.

- Scutellum green to white (depending on preservation) ( Fig. 28C, H View FIGURE 28 ); hind tibia brownish black....................... 9.

9. Flagellum white distally ( Fig. 25E View FIGURE 25 ); scutellum uniform green to white ( Fig. 28C View FIGURE 28 ); postpronotum and katatergite black, anepisternum brownish black anteriorly, green to white posteriorly; hind tarsi white apically ( Fig. 11A, B View FIGURE 11 ) (Queensland).......................................................................................... E. australis (Kertész) View in CoL .

- Flagellum entirely black ( Figs 4 View FIGURE 4 , 27K View FIGURE 27 ); scutellum with brown central marking contiguous with dark stripe on scutum ( Fig. 28H View FIGURE 28 ); postpronotum and katatergite green to white, anepisternum brownish black anteriorly, green to white dorsally and posteriorly; hind tarsi entirely black ( Fig. 11G, H View FIGURE 11 ) (Queensland, Victoria)............................... E. hauseri sp. n.