Allantus (Emphytus) cingulatus (Scopoli, 1763) (Tenthredinidae)

Liston, Andrew, 2023, Taxonomy, distribution and host plants of some southern European and North African Sawflies (Hymenoptera, Symphyta), Contributions to Entomology 73 (1), pp. 9-30 : 9

Allantus (Emphytus) cingulatus (Scopoli, 1763) (Tenthredinidae)

Tenthredo cingulata Scopoli, 1763: 277. Syntypes [assumed: probably lost or destroyed], sex not stated. Type locality: "Ruri degit" [in the countryside; presumably of Carniola (now part of Slovenia)]

Emphytus leucostomus Costa, 1890: 6-7. 2♂ syntypes [Perhaps in the Zoological Museum of the University of Naples: not examined]. Type locality: Graecia [Greece]. New synonym.

Notes.

Dalla Torre (1894) listed E. leucostomus as a valid species, but with a footnote "=? Ev. Emphytus togatus Panz.". Konow (1905a) placed it as a definite synonym of Emphytus togatus , which was followed by Taeger et al. (2010). Almost certainly, neither Dalla Torre nor Konow had examined the type specimens of E. leucostomus . The synonymy by these authors of E. leucostomus with Allantus togatus is puzzling, because few of the characters mentioned by Costa (mostly coloration) resemble A. togatus .

Costa described E. leucostomus thus:

[Translated from Latin] " Black, entire mouth, edges of pronotum, tegulae, cenchri and triangular space on abdominal tergum 1 white; legs white, apical half of the posterior femora, the tibia and tarsi pale red; wings hyaline, costa pale rufous, stigma black with white base, veins fuscous: antennae thick. ♂. - Length 9 mm".

[Translated from Italian] "Antennae slightly longer than half the body, thick, black. Head black; the lower edge of the clypeus (which is strongly emarginate in the form of an arc of a circle), the labrum and palpi, white; the outer face of the mandibles white, delicately outlined in black. Thorax black with the upper part of the edges of the pronotum and the cenchri white. Tegulae entirely white. Abdomen slender, parallel, shiny black with a white membranous equilateral triangle in the middle of the first tergum. Legs, including coxae and trochanters, white; the two hind legs with the apical half of the femora, the tibiae and the tarsi pale reddish: tarsi apically darker. Wings transparent, iridescent; the costal vein reddish, the other veins brown; the stigma blackish with a white base. The mid-discoidal vein of the forewings reaches at two-fifths towards the base of the wing the portion of the median vein interposed between the marginal discoidal vein and the first recurrent vein.

Observation.

The species it most closely resembles is E. grossulariae [ Ametastegia pallipes (Spinola, 1808)]. And, although this species is subject to variability, which causes discrepancies between the descriptions of even the most accurate writers, yet none of these descriptions squares with the species described here".

In my opinion, Costa’s description is not of Allantus togatus or one of its closer relatives such as A. enslini . Too many characters do not fit: especially the colour of the wing membranes, the abdomen, and the legs. Ghigi (1905), who was able to examine Costa’s types, concluded that Emphytus leucostomus was a valid species. He found that in morphological characters it resembled Emphytus rufocinctus (Retzius, 1783), a species of Allantus subgenus Emphytus , rather than an Ametastegia species. The species which most closely matches the description of E. leucostomus is Allantus cingulatus (Scopoli, 1763). Both sexes of A. cingulatus display significant variability, particularly in the colour of the abdomen and the legs. Several male specimens in the SDEI fit the description of E. leucostomus very well, except that even the specimen with the palest legs still has basally black coxae.