Oosagitta angolensis ( Laboissière, 1939 ) Kortenhaus & Wagner, 2013

Kortenhaus, Sabine & Wagner, Thomas, 2013, Oosagitta gen. nov. from tropical Africa, with revision of two species and description of four new species (Coleoptera: Chrysomelidae, Galerucinae), European Journal of Taxonomy 58, pp. 1-24 : 6-10

Oosagitta angolensis ( Laboissière, 1939) comb. nov.

Figs 2-9

Exosoma angolensis Laboissière, 1939: 112-113 .

Differential diagnosis

Oosagitta angolensis comb. nov. has a brown head and pronotum and yellowish elytron, brown legs and underside, while O. geescheae sp. nov. has a brown pattern on yellowish elytron, legs and underside yellowish, O. thomasi sp. nov. is yellowish with brown antennae – except the basal antennal article, O. melanoptica sp. nov. and O. anningae sp. nov. are completely yellowish and O. minuta comb. nov. has a dark brown elytron, legs and underside and is much smaller. Oosagitta angolensis comb. nov. is on average the largest species of the group, and, in the majority of cases, can be easily differentiated from other species by size. Total body length varies between 4.90 and 6.20 mm ( O. geescheae sp. nov. 4.50–4.80 mm, O. anningae sp. nov. 4.25–5.35 mm, O. minuta comb. nov. 3.10–4.20 mm, O. thomasi sp. nov. 4.65–5.50 mm, O. melanoptica sp. nov. 4.15–4.70 mm). The shape of the median lobe with slender, incised apex, long tectum with very slender tectorial spures allows a clear identification of the males.

Type material

Holotype

♂, “Kuvangu mars 1933 / Angola Miss. Sc. Suisse, 1932-33 / Coll. R. I Sc. N. B. / Exosoma angolensis m., V. Laboissière – Det. 1939/ Holotype /AfriGa specimen 753, documented 25.VII.2005 ” ( IRSNB). ( Fig. 9 ).

Type locality

ANGOLA: -14.4/16.4.

Other material examined

DEMOCRATIC REPUBLIC OF THE CONGO: 2 exx., Kasenga, -10.36/28.63, Feb. 1912, Dr. Bequaert ( MRAC); 68 exx., Lulua, Kapanga, -8.35/22.58, Dec. 1931, G.F. Overlaet ( MRAC); 6 exx., Lulua, Sandoa, -9.68/22.86, Jan.–Dec. 1931, G.F. Overlaet ( MRAC); 5 exx., Lulua, Tshibamba, -8.25/24.37, Dec. 1931, G.F. Overlaet ( MRAC); 41 exx., Lulua, Sandoa, Jan.–Dec. 1932, G.F. Overlaet ( MRAC); 274 exx., Lulua, Tshibamba, Jan./ Feb. 1932, G.F. Overlaet ( MRAC); 1 ex., Kafakumba, -9.68/23.73, Dec. 1932, G.F. Overlaet ( MRAC); 625 exx., Lulua, Kapanga, Sep.–Dec. 1932, G.F. Overlaet ( MRAC); 316 exx., Lulua, Kapanga, May–Dec. 1933, G.F. Overlaet ( MRAC); 11 exx., Mukonkoto, -10.30/23.95, Jan. 1937 ( IRSNB); 7 exx., Lulua: Kabomba, -6.20/22.37, Nov. 1937, Vanderstichele ( MRAC); 1 ex., Lulua: Kabomba, Dec. 1937, Garlier ( MRAC); 1 ex., Ngowa-Kwango, Dec. 1938, P. J. Mertens ( IRSNB); 1 ex., Maka-Lualaba, 3.13/26.78, Jan. 1939, H.J. Bredo ( IRSNB); 2 exx., Musosa, -8.38/29.63, Sep. 1939, H.J. Bredo ( IRSNB); 4 exx., Mabwe, r.E. lac Upemba, 585 m, -8.65/26.52, Dec. 1948, Miss. G.F. de Witte ( IRSNB); 1 ex. Sankuru, Gandajika, -6.75/23.95, Oct. 1950, de Francquen ( MRAC); 1 ex., Bas-Congo, Kimwanza, -4.427/18.33, May 1956, Van Eyen ( MRAC).

KENYA: 1 ex., Voi, 2000 ft, -3.39/38.56, Nov. 1948, J.G. Williams ( BMNH).

NAMIBIA: 1 ex., Bushmanland: Klein Dobe, -19.42/20.35, Feb. 1992, Namibia Expedition ZMB, M. Uhlig ( MNHU).

UGANDA: 15 exx., District Masindi, Budono Forest n. Sonso, 1.75/31.58, Jul. 1995, Th. Wagner ( ZFMK).

ZAMBIA: 16 exx., Kabwé, -9.12/30.67, Feb. 1944, H.J. Bredo ( IRSNB), 6 exx., Mweru-Wantipa, -8.75/29.50, Mar. 1944, H.J. Bredo ( IRSNB); 4 exx., 29 km NW Chipata, Kamanga, 825 m, -13.50/30.48, Mar. 1993, M. Uhlig ( MNHU).

Redescription

MEASUREMENTS. n = 30, total length 4.90–6.20 mm (mean 5.54 mm; Fig. 2 ); maximum height in lateral view 1.75–2.35 mm (mean 2.00 mm); ( Fig. 3 ).

HEAD. Brown. Maximum width of eye to minimum distance between eyes 0.57–0.77 (mean 0.67). Length of second to third antennomere 0.46–0.75 (mean 0.58), length third to fourth antennomere 0.59–0.81 (mean 0.69; Fig. 5 ). Antennae brown. Mean antennal length to total body length ratio 0.82.

THORAX. Brown as head. Pronotum brown with delicate punctation on the flat disc. Pronotal width 1.60–2.00 mm (mean 1.85 mm), length of pronotum 1.00– 1.30 mm (mean 1.17 mm), pronotal width to length 1.43–1.67 (mean 1.59). Elytron yellow to yellowish-brown with irregular, coarse punctation. Elytral length 3.70–4.75 mm (mean 4.28 mm), maximum width of both elytra combined 2.80–3.70 mm (mean 3.31 mm), ratio of maximum width of elytra combined to length of elytron 0.71–0.87 (mean 0.77). Scutellum brown, delicate punctation like pronotum. Underside and legs entirely brown. Length of basimetatarsus to length of metatibia 0.27–0.31 (mean 0.30).

ABDOMEN. Brown.

MALE GENITALIA. Median lobe slightly waisted in dorsal view ( Fig. 7A ), conical and incised at apex. Tectum is conical with a very elongated, slender apical part that is bent ventrally at the apex. It has long, slender tectorial spures at each side ( Fig. 7A, C ). Endophallus brush emerges from broad, arrow-like structure ( Fig. 7B ). Orifice of median lobe is ovoid with a rather deep incision ( Fig. 7A ).

Distribution

Widely distributed in Central, East and Southern Africa, from the Congo Basin towards Kenya in the northeast and to Zambia and northern Namibia in the South ( Fig. 8 ).

Figures

Figs 2-4. Oosagitta angolensis comb. nov. 2. Habitus, semi-schematic dorsal view, ♀. 3. Habitus, lateral view, ♀. 4. Legs: A. Prothoracic leg. B. Mesothoracic leg. C. Metathoracic leg. Scale bars = 1 mm.

Figs 5-7. Oosagitta angolensis comb. nov. 5. Basal four antennomeres of 2 ♂♂ and 2 ♀♀. 6. Spermathecae of 3 ♀♀. 7. Median lobe: A. Dorsal. B. Detail: apex of endophallus. C. Lateral. Scale bars = 1 mm.

Fig. 8. Distribution of O. angolensis comb. nov., O. melanopicta sp. nov. and O. thomasi sp. nov.

Fig. 9. Holotype of Oosagitta angolensis comb. nov. A. Overview with labels. B. Close-up of specimen.