Ootheca proteus ( Chapuis, 1879 )

Kortenhaus, Sabine & Wagner, Thomas, 2010, Revision of Ootheca Chevrolat, 1837 from tropical Africa — redescriptions, descriptions of new species and identification key (Coleoptera: Chrysomelidae, Galerucinae), Zootaxa 2659, pp. 1-52 : 14-18

Ootheca proteus ( Chapuis, 1879)

( Figs 17–23 )

Ergana proteus Chapuis, 1879: 28 .

= Ootheca bifrons Laboissière, 1925 : in litteris = Ergana bifrons Laboissière, 1937: 150 ; syn. nov.

Total length. 4.60–7.65 mm (mean: 5.98 mm; n = 15; Fig. 17 ).

Head. Brownish, all shades from yellowish to dark brown, or black. Antennae yellowish-brown at base, fifth to terminal antennomeres brown to black; length ratios, second to third antennomere 0.50–0.71 (mean: 0.59); third to fourth antennal antennomere 0.71–1.00 (mean: 0.88; Fig. 18 ). Maximal width of eye to minimal distance between eyes ratio 0.45–0.57 (mean: 0.51).

Thorax. Yellowish-brown, dark brown or black. Pronotum finely punctuated, latero-basal curved pronotal impression distinct in most specimens; width 2.00– 3.15 mm (mean: 2.58 mm), length 1.15–1.65 mm (mean: 1.44 mm), width to length ratio 1.65–1.91 (mean: 1.80). About 50 % of specimens examined with yellow to yellowish-brown elytra with dark brown to black sutural band, more or less broad usually narrowing gradually towards apex, some of these specimens with additional narrow black sublateral elytral stripe ( Fig. 19 ). Pronotum of specimens displaying this stripe either brown or black with yellowish lateral margins. About 35 % of specimens have completely dark brown to black elytra and 15 % possess elytra in various shades of brown. Elytra irregularly and more coarsely punctuated than pronotum; length 3.60–5.80 mm (mean: 4.72 mm); maximal width of elytra together 2.90–4.20 mm (mean: 3.67 mm); ratio of maximal elytral width together to length 0.71–0.83 (mean: 0.77). Scutellum yellowish-brown to black. Legs same colour as pro-, meso- and metathorax of the respective specimens, or unicolourous dark brown or black; length ratio of basimetatarsus to metatibia 0.19–0.26 (mean: 0.21).

Abdomen. Brownish to black as thorax.

Male genitalia. Median lobe slightly conical and ventrally curved towards apex, deeply incised apically ( Fig. 20 ). Tectum consisting of two symmetrical ventrally curved tectorial spurs slightly shorter than median lobe, bases cover endophallic brush and apices sharply pointed. Endophallic brush with two dorsally curved spines.

Diagnosis. Specimens having unicolourous yellowish-brown or dark brown to black elytra, comprise about half of the material examined, and are most similar to O. bennigseni and O. meridiana . It is not possible to distinguish these three species by external characters. They are most likely sister-species, since male genitalic patterns also show many similarities, but can be differentiated by the much deeper apical incision of the median lobe and a variation in the tectorial spurs and endophallus. Similar, and also with strong overlap in many external characters, is O. mutabilis with a relatively shorter second antennomere (length ratio of second to third antennomere 0.60–0.80; O. proteus 0.50–0.71), and O. orientalis with lateral pronotal margins usually curved to a lesser extent. However, most specimens cannot be reliably identified by external characters. Specimens with dark brown to black elytral suture, as the type specimens of Ergana bifrons ( Fig. 23 ), resemble O. julianae sp. n. ( Fig. 66 ), which is on average smaller (total length 3.72–4.96 mm; O. proteus 4.60–7.75 mm) has much larger eyes (ratio of maximum width of eye to minimal distance between eyes 0.59– 0.69; O. proteus 0.45–0.57) and usually also has broad black elytral outer margins. Ootheca proteus with sutural stripes are very similar in size and elytral colouration to O. ugandae sp. n. The only external species specific character is the anterior pronotal angles, which protrude significantly in O. ugandae sp. n. but are more rounded in O. proteus (as in O. bennigseni ). Furthermore, O. variabilis and O. julianae sp. n. possess similar colouration, but they are on average smaller. Definite allocation to species, without dissection of the male genitalia, is often not possible.

Distribution. Most specimens are from the area along the Albertine Rift known as Kivu, Democratic Republic of the Congo, Uganda and western Kenya, with single records from up to Nigeria in the west, the Ethiopian Highlands in the North and Malawi in the South ( Fig. 21 ).

Type material examined. Ergana proteus : Lectotype: female “Bogos, 1870, Keren, O. Beccari / Syntypus Ergana proteus Chapuis, 1879 / Museo Civico di Genova / AfriGa Specimen ID 888, specimen data documented 7.IV.2004 ” ( MCGD; Fig. 22 ). This designation. Type locality: Ethiopia, Keren.

Paralectotypes: 4 females, same data as lectotype (1 ex. BMNH, 3 ex. MCGD). Chapuis mentioned five different variation types according to the dorsal colouration and different colouration of tibae and tarsi. Four variations refer to entirely yellowish specimens, and the fifth is a specimen with black elytra. This type series is representative of nearly the entire colour spectrum for the species. Designation of a lectotype is necessary to fix the name to a single specimen.

Ergana bifrons : Lectotype: female “ Uganda Bussu Busoga 1909 D.re. E. Bayon / Type / Ergana bifrons m. V. Laboissière – Dét. / Mus. Civ. Genova / AfriGa Specimen ID 881, specimen data documented 7.IV. 2004 ” ( MCGD; Fig. 23 ). This designation. Type locality: Uganda, Busoga, 0°45’N / 33°30’E.

Paralectotypes: 4 ex., same data as lectotype ( MCGD); 2 females “Entebbe, Uganda, 29.III.1913, No. 2290, C. C. Gowdey / Type / Type female / Pres. by Imp. Inst. Ent. Brit. Mus. 1932–295 / Ergana (subg. Ootheca ) bifrons m. V. Laboissière – Dét.” ( BMNH). Laboissière mentioned seven specimens in his original publication, and a lectotype is herein designated to fix the name to a single specimen.

Ootheca bifrons : 1 female, “Entebbe, Uganda, 30.III.1913, C. C.Gowdey, No.2290 / Pres. By Imp. Bur. Ent. Brit. Mus. 1925-91. / Type / V. Laboissière det. 1925: Ootheca bifrons m”. Type locality: Uganda, 0°4’N / 32°28’E. This specimen was obviously labelled by Laboissière some years before he described the epithet in combination with Ergana .

Additional material examined. Congo (Democratic Republic): 3 ex., Abimva, Haut Uele, 2°46’N / 27°37’E, VI.1925, L. Burgeon ( MRAC); 1 ex., Sandoa, 9°41’S / 22°52’E, XI.1931, G. F. Overlaet ( MRAC); 2 ex., Kibali-Ituri, Niarembe, 2°15’N / 31°07’E, XI.1935, Ch. Scops ( MRAC); 2 ex., Ituri, Akini, N. Aru, 1°34’N / 30°15’E, V.1936, Dr. Pasteels ( MRAC); 1 ex., Mt. Embe, P. N. G., 4°40’N / 29°32’E, IV.1952, H. de Saeger ( IRSN); 7 ex., Inimvua, P. N. G., V.1952, H. de Saeger ( IRSN). Ethiopia: 1 ex. Abyssin., Steudner ( MNHU); 5 ex., Abyssinia, 1876, ( BMNH); 2 ex. Shoa-Prov., Gibbie Gorge, 9°00’N / 39°00’E, VII.1971, G. de Rougemont ( MRAC). Kenya: 1 ex., Nyangori, N-Kavirondo, 4800 ft, 0°04’N / 34°48’E, V.1911, S. A. Neave ( BMNH); 1 ex., Kaimosi, 0°8’N / 34°56’E, 1932, A. Turner ( NMK); 5 ex. Kisumu, 0°06’S / 34°45’E, III.1936, H. J. A. Turner ( NMK). Malawi: 2 ex., Zomba, 15°23’S / 35°20’E, IX.1995, coll. Chikaonda ( BMNH). Nigeria: 2 ex., Minna, 9°37’N / 6°33’E, X.1910, J. J. Simpson ( BMNH); 2 ex., Jos, 9°55’N / 8°54’E, 1965/ 1968, E. Bot Gwong ( MRAC). Sudan: 1 ex., Kadugli, 11°1’N / 29°43’E, VII.1962, ( BMNH). Tanzania: 1 ex., Mwamgongo, 4°40’S / 29°35’E, XI.1943, Meneghetti ( NMK). Uganda: 1 ex., Uganda, Fry coll. ( BMHN); 1 ex., Buera, IV.1910, C. C. Gowdey ( BMNH); 1 ex, West-Nile near river, IX.1925, Dr. G. D. H. Carpenter ( BMNH); 4 ex., Karamoja, 2°45’N / 34°15’E, IV.1950, T. H. E. Jackson ( NMK); 2 ex., Karamoja, Labwor Hills, Aremo, 2°35’N / 33°47’E, IV.1951, T. H. E. Jackson ( NMK).

Figures

FIGURE 21. Distribution of Ootheca proteus, O. tilmani sp. n. and O. frontalis.

FIGURE 66. Holotype of Ootheca julianae sp. n., a. specimen with labels, b. close-up detail of specimen.

FIGURES 17 – 20. Ootheca proteus (Chapuis, 1879). 17. Habitus, dorsal view; 18. Antennomeres 1 – 4 of two different males and two different females; 19. Colour pattern of some specimens; 20. Median lobe: dorsal (left), lateral (right).

FIGURES 22 – 23. Ootheca proteus (Chapuis, 1879). Type material. 22. Lectotype of Ergana proteus Chapuis, 1879, a. specimen with labels, b. close-up detail of specimen; 23. Lectotype of Ergana bifrons Laboissière, 1925, a. specimen with labels, b. close-up detail of specimen.