Thoreauella Girault, 1930

Noort, Simon van, Buffington, Matthew L. & Forshage, Mattias, 2015, Afrotropical Cynipoidea (Hymenoptera), ZooKeys 493, pp. 1-176 : 48-51

Taxon classification Animalia Hymenoptera Figitidae

Thoreauella Girault, 1930

Thoreauella (synonyms: Bothrocynips Díaz, 1978, syn. n., Emargo Weld, 1960, syn. n., Weldiola Kovalev, 1994, syn. n., Quinlania Kovalev, 1994, syn. n.)

Remarks.

Emargo and Thoreauella (and Bothriocynips ) were described at different times in different groups that are now considered different figitid subfamilies, obviously with the authors being unaware of the other generic names ( Díaz 1978, Girault 1930, Quinlan 1960). The Neotropical Bothriocynips was made a junior synonym of the Neotropical and Afrotropical Emargo by Pujade-Villar et al (2002). However nothing has been suggested to distinguish Emargo from Thoreauella except distribution ( Emargo Neotropical and Afrotropical, Thoreauella Australian), and there is no morphological evidence to support keeping them separate. Kovalev (1994), within a consideration of broad evolutionary trends in the Cynipoidea, found that some of the characters separating some of the Afrotropical Emargo species in Quinlan’s key ( Quinlan 1988) were important enough to merit separation on a higher taxonomic level and erected not just new genera but new tribes for two of Quinlan’s species from Madagascar (and a new family for the whole group). Ronquist (1995) changed the status of Kovalev’s Emarginidae into a subfamily, and made Kovalev’s Weldiolini and Quinlaniini synonyms of it, but Kovalev’s genera have remained to this date, in spite of being raised in the absence of an actual morphological study as well as of consideration of the global variation. Here we consider that at the current level of knowledge they constitute mere recognisable species or species groups among others within a single genus.

Thus, here we synonymise all genera of Emargininae, and the senior name is Thoreauella Girault. Most of the resulting new combinations are species hitherto classified as Emargo Weld, including the Neotropical type species Thoreauella eciton (Weld, 1960), comb. n. Bothriocynips was already made a synonym of Emargo but is a new synonym of Thoreauella , and its Neotropical type species is now Thoreauella recisa ( Díaz, 1978), comb. n. Quinlaniana and Weldiola were both monotypical for taxa from Madagascar and cited in the new combinations Thoreauella pexa and Thoreauella capito respectively below.

Diagnosis.

Members of the subfamily Emargininae, now coinciding with the genus Thoreauella , uniformly possess an emarginate apical margin of the forewing. The only other cynipoids to have such a character are species of Kleidotoma , but being eucoilines, the latter have a distinct scutellar plate with posterior midpit. Some emarginines have what appears to be a raised scutellar plate on the scutellum, but in these species, there is clearly an entire lack of a glandular pit. Emarginines also typically have: a very abrupt, compact marginal cell in the forewing; distinct notauli; dense ‘foamy’ setae on the propodeum and base of the metasoma; and large, setiferous pits on the flagellomeres of the male antenna.

Much species level work remains to be conducted on the Afrotropical emarginines. However, we have noted the following characteristics of currently unnamed species groups:

Species group A, which appears to be common in Madagascar, comprises species that possess notauli, and have a thin, complete, lamella along the posterior margin of the scutellum. The lamellae enclose a rather deep ‘trough’; further, the lamella is so thin that without significant magnification, it will not be visible. The presence of this resulting ‘trough’ may have led Quinlan (1988) to erroneously conclude Emargininae are actually Eucoilinae.

Species group B also possesses notauli, as well as having rather spectacular projections off the posterior margin of the scutellum. Two sub-groups can be recognized; one with a simply bifurcate scutellar margin; and a second group possessing a single projection off the posterior margin of the scutellum. Both subgroups contain the largest physical specimens of Thoreauella , with some reaching nearly 1.5 mm; further, nearly all members of this group have dark, dusky wings. Quinlan’s Thoreauella pexa , considered by Kovalev to constitute the tribe Quinlanianini , belongs in this species group. Species group B appears to be endemic to Madagascar.

Species group C possesses notauli, and is similar in overall appearance to species group A, however, species in group C lack the posterior lamella on the scutellum. Nevertheless, group C species do have a deep, marked depression on the posterior margin of the scutellum. Quinlan's Thoreauella capito , considered by Kovalev to constitute the tribe Weldiolini , belongs in this species group. Species group C is common in continental Africa (throughout the tropical belt), as well as Madagascar.

Species group D is the most widespread of the four genus groups, found equally common in Madagascar and continental Africa. The distinguishing feature of this group is the general lack of clear notauli. In some species, it is clear that the mesoscutum is perfectly smooth; in others, there are faint traces of notauli, but never as clearly indicated as in species groups A–C. The posterior margin of the scutellum in these species is rounded, lacking any remarkable morphology. Thoreauella laverna , Thoreauella micipsa , Thoreauella palloris , and Thoreauella vacuna would be included in this group.

Distribution.

Pantropical, apparently especially diverse in Madagascar. Presence in the Oriental region has not been published hitherto but is confirmed here. Afrotropical records: Cameroon, Democratic Republic of Congo, Madagascar, South Africa, Zambia, Zimbabwe ( Quinlan 1988), Central African Republic, Ghana, Nigeria, Rwanda, Tanzania, Uganda (here).

Biology.

Hosts unknown. Appear to be associated with ants ( Weld 1960, Díaz 1978).

Species richness.

Species group A

Thoreauella numa (Quinlan, 1988), comb. n. ( Emargo ) (Zimbabwe)

Species group B

Thoreauella pexa (Quinlan, 1988), comb. n. ( Emargo ) (Madagascar)

Species group C

Thoreauella ascia (Quinlan, 1988), comb. n. ( Emargo ) (Madagascar, Zambia)

Thoreauella cantus (Quinlan, 1988), comb. n. ( Emargo ) (Democratic Republic of Congo, Zimbabwe)

Thoreauella capito (Quinlan, 1988), comb. n. ( Emargo ) (Madagascar)

Thoreauella matius (Quinlan, 1988), comb. n. ( Emargo ) (Cameroon, Democratic Republic of Congo, Kenya, Zimbabwe)

Thoreauella peleus (Quinlan, 1988), comb. n. ( Emargo ) (Cameroon, Madagascar)

Thoreauella themis (Quinlan, 1988), comb. n. ( Emargo ) (Cameroon, Madagascar)

Species group D

Thoreauella laverna (Quinlan, 1988), comb. n. ( Emargo ) (Kenya, Zimbabwe)

Thoreauella micipsa (Quinlan, 1988), comb. n. ( Emargo ) (Cameroon, Democratic Republic of Congo, Madagascar)

Thoreauella palloris (Quinlan, 1988), comb. n. ( Emargo ) (Democratic Republic of Congo)

Thoreauella vacuna (Quinlan, 1988), comb. n. ( Emargo ) (South Africa)