Phryganomelus auriventer Jago, 1983

Popov †, George B., Fishpool, Lincoln D. C. & Rowell, C. Hugh F., 2019, A review of the Acridinae s. str. (Orthoptera: Acridoidea: Acrididae) of eastern Africa with taxonomic changes and description of new taxa, Journal of Orthoptera Research 28 (2), pp. 37-105 : 85-86

Phryganomelus auriventer Jago, 1983 Fig. 364

Phryganomelus auriventer Jago, 1983a: 155.

Material.

-Holotype male: UGANDA: Mabira forest, nr. Jinja, 33°00'E 00°25'N, 28.IV.67, and paratypes.

Description.

-Closely resembles P. phalangidus Jago, 1983, but differs from it as follows: slightly larger size (in mm: total length males 23-28, females 32-36), and more massive hind femora; fore and mid-legs olive green; hind femora light brown above, outer areas olive green, lower surfaces yellow to pale green; underside of thorax and proximal sternites of abdomen yellow to pale green, not orange. Detailed structure of apex of male abdomen differs between the two species (compare Figs 364 and 361).

Distribution.

-UGANDA: In forests west of the Nile outlet from Lake Victoria, but always much rarer than P. phalangidus .

2.4 Transitional genera of uncertain position

Genus group diagnosis

The Aiolopus - Uganda genus group and Dorsthippus

Description.-Outlined in Diagnosis of Tribes and Genus Groups, above, Page 39. Defined on basis of male and female genitalia.

Discussion.-This assemblage contains a group of four genera - Aiolopus , Jasomenia , Paracinema , Uganda - and Dorsthippus . Their peculiarity lies in that they fit the definitions of neither of the two subfamilies Oedipodinae or Acridinae . The Oedipodinae are considered to be characterized by their femoral/tegminal sound-producing mechanism, the sound being produced by the rubbing of a sharp carinula on the inner side of the hind femur against a prominent serrated inter-calary vein, usually in the medial area of tegmina; the Acridinae lack this mechanism, or it is vestigial and said to be incapable of sound-production. Generally, there is little ambiguity in attributing a given genus to one or other of these two subfamilies on the basis of the above distinction. The four genera listed possess a well-developed intercalary vein but in some it lacks the necessary serrations for sound production. Also, their rather slender build and hygrotypic habitat associations are more characteristic of the Acridinae than the Oedipodinae . They are thus at the root of the controversy surrounding the separate identity of the two subfamilies.

Importantly, Slifer (1939) described the presence of a loop at the proximal end of the female spermathecal duct in Acridinae , but which is absent in Oedipodinae . All the four genera considered here lack the proximal loop, and should, therefore, be placed in the Oedipodinae rather than Acridinae . Absence of serrations on the intercalary vein may thus be attributable to secondary loss.

Editorial note.-As discussed in the Introduction we consider these four genera to be most usefully classified as Oedipodinae , rather than Acridinae , and omit further treatment of them here. Dorsthippus is also discussed on p. 42.