Lagenosoma Brauer

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 : 29-31

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.7675151
persistent identifier	https://treatment.plazi.org/id/726B879C-FF87-0253-FF56-285DDDECFC30
treatment provided by	Plazi
scientific name	Lagenosoma Brauer
status

Treatment

Lagenosoma Brauer View in CoL View at ENA

Lagenosoma Brauer 1882: 81 View in CoL — Hardy, 1920: 46 [as synonym of Massicyta ]; Hardy, 1933: 409; Woodley, 1989: 314 [catalogue], 2001: 168 [catalogue]. Type species: Lagenosoma picta Brauer, 1882: 81 View in CoL , by original designation.

Peratomastix Enderlein, 1914: 311 View in CoL — Kertész, 1916: 128 [key]; Hardy, 1920: 46 [checklist]; Hardy, 1933: 409 [key]; Woodley, 1989: 311 [catalogue], 2001: 131 [catalogue]. Type species: Peratomastix australis Enderlein, 1914: 311 View in CoL , by original designation. syn. n.

Diagnosis. Scutellar and notopleural spines absent; wing vein M 3 present; M 4 arising on discal cell, cross-vein r–m present; wing not bent over abdomen; face flat or broadly rounded, including around base of antennae, sometimes extended ventrally around buccal cavity; male eyes usually contiguous medially below ocellar tubercle; eye not pilose; male postocular ridge narrow or 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, flagellomeres VI–VII length variable; flagellomere VIII longer than all other flagellomeres, covered with shallow to deeply plumose microtrichia; abdomen narrowed basally, ovoid to strongly petiolate, frequently strongly sexually dimorphic.

Included species. Lagenosoma clitellum sp. n.; L. danielsorum sp. n.; L. dimorphum sp. n.; L. dispar Brauer, 1882 (= Peratomastix australis Enderlein, 1914 syn. n.); L. eklemmum sp. n.; L. geminatum sp. n.; L. pictum Brauer, 1882 ; L. propinquum Brauer, 1882 ; L. propius sp. n. and L. varigatum sp. n.

Comments. Lagenosoma is easily differentiated from other clitellariine genera by the absence of scutellar (cf. Campeprosopa and Elissoma ) and notopleural spines (cf. Nigritomyia ), a rounded or flat face (cf. Ampsalis ), and abdomen narrowed anteriorly, especially in the male (cf. ovoid in Eudmeta ). The distal antennal flagellomere is elongate (aristate in Geranopus and Dysbiota ) and slightly to narrowly plumose (shared with Ampsalis , Lagenosoma , Elissoma and Eudmeta ); all other genera have flagellomere VIII subequal to, or shorter than, one or more other flagellomeres. The male abdomen is frequently strongly petiolate while the female is slightly petiolate to broadly ovoid. Members of this genus are excellent wasp mimics, especially L. pictum . All species are distributed in mainland eastern Australia, with the greatest diversity found in Queensland ( Fig. 37 View FIGURE 37 ).

Brauer (1882) incorrectly attributed Lagenosoma to Schiner, but subsequent authors have correctly attributed the genus to Brauer. Moreover, Brauer (1882) did not list the gender of Lagenosoma , but Woodley (1989, 2001) used it in the diminutive neuter form (as it ends in – soma) (the combination describes the narrow male abdomen); the neuter form is similarly used here. Hardy (1920) listed Massicyta Walker, 1856 as a senior synonym of Lagenosoma , but as noted by Brauer (1882) when describing Lagenosoma , Massicyta is poorly defined and actually belongs in Hermetiinae . Woodley (2001) subsequently synonymised Massicyta with Hermetia Latreille, 1804 . Enderlein (1914) described Peratomastix based on a damaged female specimen and placed it in Pachygastrinae; he supposed that it had three medial veins to place it in that subfamily, despite it lacking a complete wing. Placement of Peratomastix in Pachygastrinae was followed by Kertész (1916), Hardy (1920) (as Lophotellinae) and Woodley (1989, 2001). Interestingly, Hardy (1920) questioned the assumption of the medial vein complement in Peratomastix by Enderlein (1914), based on his assessment of variation in wing venation in a wide variety of Australian forms and indeed cautioned against such assumptions. Hardy (1933) in his key to genera instead suggested Lagenosoma was equivalent to Peratomastix and placed both in Hermetiinae . Based on the similarity of Peratomastix to Lagenosoma it is synonymised here and it is clear that Enderlein (1914) was incorrect both in his assumption of its wing medial vein complement and thus its placement in Pachygastrinae.

Key to species of Lagenosoma View in CoL

1. Wing hyaline; scutum and scutellum entirely or partly straminous orange to brown with glossy black punctate setal bases (e.g., Fig. 16C, G View FIGURE 16 ); male postocular ridge slightly to strongly carinate (e.g., Figs 27C View FIGURE 27 ; 26C View FIGURE 26 )............................. 2.

- At least part of wing smoky infuscate; scutum and scutellum colour variable, bright yellow to black, setal bases not punctate, concolourous with rest of scutum and scutellum (e.g., Fig. 15B, C View FIGURE 15 ); male postocular ridge rarely carinate ( Fig. 26E, G View FIGURE 26 )... 4.

2. Scutum black anteriorly with yellowish dorsocentral stripes ( Fig. 14E, H View FIGURE 14 ); male abdomen strongly petiolate (segments 1–3) ( Fig. 14F View FIGURE 14 ), abdomen ovoid in female; postocular ridge whitish ( Fig. 26C, D View FIGURE 26 ); wing membrane in cells bm and d lacking microtrichia ( Fig. 14E–H View FIGURE 14 )..................................................................... L. clitellum View in CoL sp. n.

- Scutum entirely dark yellow and lacking dorsocentral stripes ( Fig. 16C, F, G View FIGURE 16 ); abdomen narrowed basally but not petiolate and not sexually dimorphic; postocular ridge concolourous with rest of head and thorax ( Fig. 27A–D View FIGURE 27 ); wing membrane in cells bm and d with microtrichia............................................................................... 3.

3. Pleuron entirely dark yellow ( Fig. 16E, H View FIGURE 16 ); male occiput strongly carinate ( Fig. 27C View FIGURE 27 )............... L. geminatum View in CoL sp. n.

- Pleuron dark brownish black, extending ventrally between fore and mid coxae (katepisternum), more extensive in male ( Fig. 16A, D View FIGURE 16 ); male occiput weakly carinate ( Fig. 27A View FIGURE 27 )........................................... L. eklemmum View in CoL sp. n.

4. Male (eyes contiguous medially, or near so)............................................................... 5.

- Female (eyes widely separated medially)............................................................... 11 *.

5. Wing with distinct darker infuscation anteriorly ( Fig. 21D View FIGURE 21 ); abdomen strongly petiolate (33G); scutum with yellow areas laterally on notopleuron, postalar callus and anterior to transverse suture ( Fig. 17A, B View FIGURE 17 ).............. L. pictum Brauer View in CoL (male).

- Wing with more diffuse smoky infuscation throughout; abdomen slightly narrow basally to strongly petiolate, but not globose; scutum entirely black................................................................................. 6.

6. Scutellum pale, usually yellow to white ( Fig. 30E View FIGURE 30 ).................................. L. propinquum Brauer View in CoL (male).

- Scutellum entirely black, or black anteromedially............................................................ 7.

7. Scutellum black with distinctly demarcated yellow border ( Fig. 30G View FIGURE 30 ); margin of buccal area extended ventrally ( Fig. 27I View FIGURE 27 )................................................................................. L. varigatum sp. n. (male).

— Scutellum entirely brown or black...................................................................... 8.

8. Abdomen (segments 1–3) narrowed basally, sides relatively straight and diverging ( Fig. 33E View FIGURE 33 ); area around base of antennae suffused with black ( Fig. 26K View FIGURE 26 ; 15E, F View FIGURE 15 )................................................. L. dispar Brauer View in CoL (male).

- Abdomen (segments 1–3) more strongly petiolate, sides curved inwards (e.g., Fig. 33A View FIGURE 33 ); area around base of antennae yellow ( Fig. 26E, G View FIGURE 26 )....................................................................................... 9.

9. Face and area around base of antennae only slightly rounded ( Fig. 27L View FIGURE 27 ); abdominal tergites with narrow margin of dark yellow ( Figs 18A View FIGURE 18 ; 34B View FIGURE 34 )................................................................... L. propius View in CoL sp. n. (male).

- Face and area around base of antennae raised, rounded; abdomen entirely black................................. 10.

10. Head entirely yellow, face with few black setae, ( Fig. 26G View FIGURE 26 ; 15A, B View FIGURE 15 )...................... L. dimorphum View in CoL sp. n. (male).

- Head dull yellow anteriorly, face with extensive black setae, occiput mostly black or suffused with black ( Figs 14A, B View FIGURE 14 ; 26E View FIGURE 26 )............................................................................ L. danielsorum View in CoL sp. n. (male).

11. Abdomen strongly petiolate, globose posteriorly ( Figs 17D, F View FIGURE 17 ; 33H View FIGURE 33 )......................... L. pictum Brauer View in CoL (female).

- Abdomen narrowed basally but not strongly petiolate (e.g., Fig. 33D, F, L View FIGURE 33 )..................................... 12.

12. Margin of buccal area extended ventrally ( Fig. 27J View FIGURE 27 ); scutum yellow with single broad black stripe and narrower interrupted stripe laterally ( Fig. 18E View FIGURE 18 ); terminal flagellomere relatively short and not plumose........... L. varigatum sp. n. (female).

- Margin of buccal area not extended ventrally; scutum otherwise patterned; terminal flagellomere relatively elongate and plumose............................................................................................. 13.

13. Scutellum black, usually with narrow dark yellow margin posteriorly ( Fig. 29J View FIGURE 29 )............... L. dispar Brauer View in CoL (female).

- Scutellum otherwise, mostly dark yellow or teal green to white.............................................. 14.

14. Scutellum dark yellow with brown-black suffusion laterally ( Fig. 29H View FIGURE 29 ); abdomen black with distinct white intersegmental membrane ( Fig. 33D View FIGURE 33 )......................................................... L. dimorphum View in CoL sp. n. (female).

- Scutellum uniform bright yellow ( Fig. 30F View FIGURE 30 ) or teal green to white ( Fig. 29F View FIGURE 29 ); abdomen uniform dark brown ( Fig. 33B, J View FIGURE 33 ).................................................................................................... 15.

15. Scutellum bright yellow ( Fig. 30F View FIGURE 30 ); frons unmarked ( Fig. 27H View FIGURE 27 )...................... L. propinquum Brauer View in CoL (female).

- Scutellum teal green (tending to white in dried specimens) ( Fig. 29F View FIGURE 29 ); frons with pair of black spots ( Fig. 26F View FIGURE 26 )..................................................................................... L. danielsorum View in CoL sp. n. (female).

*Note: the female of L. propius View in CoL sp. n. is unknown.