Rhoptromeris Foerster , 1869

Noort, Simon van, Buffington, Matthew L. & Forshage, Mattias, 2015, Afrotropical Cynipoidea (Hymenoptera), ZooKeys 493, pp. 1-176 : 107-110

Taxon classification Animalia Hymenoptera Figitidae

Rhoptromeris Foerster, 1869

Remarks.

Ubiquitous; the most common genus of eucoilines in Africa. This taxon keys out three times in the generic key above, which reflects the morphological plasticity and complexity of the genus. Though many Afrotropical species have been described, there are undoubtedly many more undescribed species awaiting description. Further, Quinlan’s (1986) reliance on antennal characters to separate species within Rhoptromeris will have to be revisited too, since antennal characters themselves without other characters are frequently unreliable in figitid taxonomy.

Diagnosis.

Mostly small and elongate eucoilines, with narrow wings and a narrow triangular marginal cell. Males usually have a strongly modified antennal F2. Rhoptromeris are easily recognised by the combination of a pronotal plate with lateral bridges, a scutellum lacking a protruding posterior lobe, and the dorsal surface of the scutellum distinctly striate, especially anteriorly. These characters separate the genus from the morphologically similar Trichoplasta . However, intermediate forms between these two genera have been examined, creating difficulties in separating the two genera; in these cases, focusing on the striate dorsal surface of the scutellum will reliably run these species in the key. If the pronotal plate is not obvious, the diversity of morphotypes of Rhoptromeris in this region may create confusion with several other genera.

The most common Afrotropical specimens are small, brown and elongate; have narrow elongate wings with a narrow triangular marginal cell; and have a circular incision near metapleural corner. Some, often larger, have a more elongate incised (or depressed) area along metapleural posterior margin. These may possibly be mistaken for several other eucoiline genera of a similar general build; Hexacola , Ganaspis , Kleidotoma or Cothonaspis . Rhoptromeris is separated from all of these by the pronotal plate, from all but Cothonaspis by the male antennae, and from most of these genera by differences in the metapleuron and scutellar plate.

Larger taxa are in general stouter, less elongate, have darker colour, broader wings, a deeper marginal cell and a shorter hair fringe on the wings; and approach Leptopilina or some Trybliographa or Trichoplasta in appearance.

A distinct species group is represented by tiny specimens with an indistinct or absent mesopleural line, a very long hair fringe on the wing, and often a shorter marginal cell; these are superficially very similar to Micreriodes and Endecameris , but easily recognised by their pronotal plate.

Another distinct species group have a pointed posterior lobe of the scutellum and are very easily confused with Trichoplasta ; separated only by the general build of the scutellum, which has a convex scutellar plate and at least partly smooth or lineate sculpture of the dorsal surface. Of these we have seen a small, stout black taxon from South Africa, a large dark brown taxon from Uganda, and some less characteristic small brown forms from elsewhere.

One or several species groups have protuberances on the face, small often pointed tubercles on the clypeus and/or malar spaces and sometimes modified mandibles; they are small or tiny, and more stoutly built than typical Rhoptromeris ; their appearance approaches Nanocthulhu or Stentorceps , both of which have more spectacular facial protuberances. Most of these specimens are from South Africa, but we have also seen singletons from East African countries.

Distribution.

Worldwide. Afrotropical records: Cameroon, Democratic Republic of Congo, Kenya, Madagascar, Nigeria, Reunion, South Africa, Uganda ( Quinlan 1986), Botswana, Burkina Faso, Cape Verde, Central African Republic, Comoros, Ethiopia, Gabon, Ghana, Ivory Coast, Malawi, Republic of Congo, Rwanda, Senegal, Seychelles, Sierra Leone, Tanzania, Zimbabwe, Yemen (here).

Biology.

As far as known they attack Chloropidae on grasses and fungi (numerous sources including Bhattacharyya 1957, Quinlan 1978, Nordlander 1978, Nordlander and Grijpma 1991), but no certain records are from within the Afrotropical region.

Species richness.

Rhoptromeris abba Quinlan, 1986 (Democratic Republic of Congo, Kenya)

Rhoptromeris afer Quinlan, 1986 (Democratic Republic of Congo, Uganda)

Rhoptromeris agis Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris attis Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris bicolor Quinlan, 1986 (Democratic Republic of Congo, Nigeria, Zimbabwe)

Rhoptromeris bupalus Quinlan, 1986 (Democratic Republic of Congo, Kenya, Reunion, Uganda, Zimbabwe)

Rhoptromeris cepheus Quinlan, 1986 (Kenya)

Rhoptromeris connata Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris crito Quinlan, 1986 (Madagascar)

Rhoptromeris cubitalis Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris diversa Quinlan, 1986 (Democratic Republic of Congo, South Africa, Uganda)

Rhoptromeris enna Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris equalis Quinlan, 1986 (Cameroon, Democratic Republic of Congo)

Rhoptromeris hebe Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris heptoma (Hartig, 1840) (Democratic Republic of Congo, South Africa; Palearctic species)

Rhoptromeris navius Quinlan, 1986 (Democratic Republic of Congo, Kenya, Zimbabwe)

Rhoptromeris naxos Quinlan, 1986 (Democratic Republic of Congo, Uganda)

Rhoptromeris oeta Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris pagasa Quinlan, 1986 (Cameroon, Democratic Republic of Congo)

Rhoptromeris pallida Quinlan, 1986 (Democratic Republic of Congo, Nigeria)

Rhoptromeris persius Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris punctata Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris rufula Quinlan, 1986 (Democratic Republic of Congo, South Africa)

Rhoptromeris rutshuris Quinlan, 1986 (Cameroon, Democratic Republic of Congo)

Rhoptromeris rwanki Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris sinis Quinlan, 1986 (Cameroon, Democratic Republic of Congo)

Rhoptromeris temesa Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris thales Quinlan, 1986 (Democratic Republic of Congo, South Africa)

Rhoptromeris velia Quinlan, 1986 (Democratic Republic of Congo, South Africa)

Rhoptromeris zetes Quinlan, 1986 (Democratic Republic of Congo)

Rhoptromeris zeus Quinlan, 1986 (Democratic Republic of Congo)