Megaprosternum longiceps ( Ashmead, 1900 )

Colombo, Wesley D. & Azevedo, Celso O., 2024, Revision of the strongly flattened Megaprosternum Azevedo (Hymenoptera, Bethylidae), European Journal of Taxonomy 958 (1), pp. 1-47 : 22-24

Megaprosternum longiceps ( Ashmead, 1900)

Fig. 8

Ateleopterus longiceps Ashmead, 1900: 327‒328 .

Sclerodermus longiceps – Gordh & Móczár 1900: 162.

Neoscleroderma longiceps – Kieffer 1908: 40; 1914: 270‒271.

Megaprosternum longiceps – Azevedo et al. 2018: 235. — Vargas et al. 2020: 219.

Megaprosternum longiceps – Lanes & Azevedo 2008: 81 [nec A. longiceps Ashmead, 1900 ].

Differential diagnosis

The females of this species differ from those of the other species by having the body length ranging from 4.4 to 4.6 mm, antennae with 10 flagellomeres, the median clypeal lobe with parallel lateral carinae, and the postocellar line longer than DAO, and the inconspicuous transscutal fissure.

Material examined

Syntypes

AUSTRALIA – New South Wales • 4 ♀♀; “N[ew] S[outh] W[ales], Rose Bay, near Sydney , 6.III.1892, bred by Mr. Froggatt from hollow stem of Acacia discolor , type 4870”; USNMENT 01583000 .

Non-types

AUSTRALIA – New South Wales • 2 ♀♀; “ Rose Bay, “Hollow stem of Acacia discolor ”, 3.vi.[19]92, (Froggatti coll., 92.164)”; NHMUK 015663885 , 015663886 . [The latter was previously identified as M. longiceps Azevedo, 2006 by Lanes et al. 2008.]

Redescription

Female

MEASUREMENTS (mm). Body length 4.4‒4.6; LH 0.85; WH 0.49; WF 0.26; WOT 0.11; surface of median clypeal lobe 0.11; HE 0.25; OOL 0.38; LFW 1.9‒2.4.

COLOR ( Fig. 8A–C ). Head, mesosoma and metasoma castaneous.

HEAD ( Fig. 8D ). Oval, in lateral view; sides almost parallel, in dorsal view; malar space 0.1× HE; median clypeal lobe straight, as long as lateral ones, with pair of lateral carinae, parallel posteriorly, lobe delimitation distinct; mandible with three apical teeth; hypostoma rounded medially; antenna with 10 flagellomeres, pedicel as long as flagellomere I; eye weakly setose, contour not protruding; frons coriaceous; ocellar triangle with anterior angle acute, postocellar line longer than DAO.

MESOSOMA. Pronotal flange coriaceous, with posterior margin at least 1.6 × as wide as anterior one; dorsal pronotal area coriaceous, posterior margin outcurved medially, overlapping anterior area of mesoscutum; probasisternum with anterior margin strongly angulated, posterior margin almost straight; mesoscutum longer than mesoscutellum medially; parapsidal signum absent; transscutal fissure inconspicuous; mesoscuto-scutellar suture absent; mesopleuron with mesopleural pit present; metapectal-propodeal disc longer than wide medially, without evident constriction at propodeal spiracle; transverse anterior carina absent; lateral marginal carina absent; paraspiracular sulcus absent; paraspiracular carina absent; metapostnotal median carina absent; propodeal spiracle circular, on lateral surface of the metapectal-propodeal complex; forewing with prestigmal abscissa of radial 1 oval, 3.0 × as long as pterostigma, 2.0× as wide as Sc+R vein, prestigmal flexion line present, pterostigma small and circular; hind wing with three non-equidistant distal hamuli.

METASOMA. Second abdominal spiracle circular; abdominal tergum widening apicad.

Male

Unknown.

Variations

There are no morphological variations worthy of mention.

Remarks

This species was described based on four female specimens collected in New South Wales, Australia. In the original description, Ashmead (1900: 328) mentioned that the holotype is the specimen labeled “type-Nº. 4870”. However, all four specimens were mounted on the same card and share identical labels, including the one with the mentioned type number ( Fig. 8E ). As a result, it is not possible to identify the holotype, and for this reason, we conclude that these specimens are all syntypes.

Host

Unknown.

Distribution

Australia (New South Wales).

Figures

Fig. 8. Megaprosternum longiceps (Ashmead, 1900), syntypes, ♀♀ (USNMENT 01583000). A–C. Habitus. A. Dorsal view. B. Lateral view. C. Dorsal view of right specimen on figure A. D. Head, dorsal view. E. Labels. Scale bars: A–C = 500 μm; D = 125 μm.