Oosagitta melanopicta, 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 : 21-23

Oosagitta melanopicta sp. nov.

urn:lsid:zoobank.org:act:4E493FBA-DE58-4EE4-9DE4-79D63C0FD211

Figs 8 , 27-30

Differential diagnosis

Oosagitta melanoptica sp. nov. has a peculiar character in the significant black patch behind the eye. Further differentiation is possible by the characteristic broad shape of the median lobe.

Etymology

Named after the significant dark brown postocular patch.

Type material

Holotype

♂, “Coll. Mus. Congo, Stanleyville: Yangambi, km 7, 29.V.1956, R. Damoiseau, C.00.53/ Récolté sur Canvalaria curiformis/AfriGa specimen ID 1900, 15.III.2013 ” ( MRAC).

Paratypes

DEMOCRATIC REPUBLIC OF THE CONGO: 1 ♂, 2 ♀♀, same data as holotype; 1 ♂, Mayidi, -5.19/15.15, 1942, P. Van Eyen ( MRAC).

Type locality

DEMOCRATIC REPUBLIC OF THE CONGO: Stanleyville [Kisangani], Yangambi, 0.81/24.43.

Description

MEASUREMENTS. n = 5, total length 4.20–4.70 mm (mean 4.42 mm; Fig. 27 ); maximum height in lateral view 1.80–2.20 mm (mean 1.95 mm).

HEAD. Yellowish, dark brown postocular patch, labrum brown. Maximum width of eye to minimum distance between eyes 0.63–0.75 (mean 0.71). Length of second to third antennomere 0.58–0.67 (mean 0.61), length third to fourth antennomere 0.63–0.77 (mean 0.70; Fig. 28 ). Antennae yellowish. Antennal length to total body length 0.87–0.98 (mean 0.91).

THORAX. Yellowish. Pronotum yellowish nearly without punctation. Pronotal width 1.50–1.75 mm (mean 1.61 mm), length of pronotum 0.85–1.00 mm (mean 0.92 mm), pronotal width to length 1.65–1.94 (mean 1.76). The elytron is yellowish and has delicate brown margins and an irregular coarse punctation. Elytral length 3.05–3.75 mm (mean 3.35 mm), maximum width of both elytra combined 2.60–3.15 mm (mean 2.94 mm), ratio of maximum width of elytra combined to length of elytron 0.81–0.97 (mean 0.88). Metathorax more yellow than pro- and mesothorax and abdomen. Legs paler yellowish. Length of basimetatarsus to length of metatibia 0.29–0.33 (mean 0.31).

MALE GENITALIA. The symmetric conical aedeagus slightly curved ventrally, median lobe tapers to a short point ( Fig. 29A, B ). Tectum with very broad base, which narrows to a ventrally bent, flattened structure. Very long, slender and strongly curved tectorial spures intersect themselves nearly at the apex. Apically these structures are curved dorsally ( Fig. 29A, B ). Endophallus brush is emerging from the arrow-like endophallus ( Fig. 29A ). Orifice of median lobe ovoid with a rather great incision ( Fig. 29A ).

Distribution

Only known from two sites along the Congo River ( Fig. 8 ).

Identification key

1. Elytra dark brown, total body length <4.20 mm, tectum shorter than median lobe with hooked tectorial spurs ( Fig. 12A, C ); Uganda, SE Congo and northern states of South Africa ( Fig. 13 ) ....... .............................................................................. Oosagitta minuta ( Laboissière, 1937) comb. nov.

– Elytra mainly yellowish, total body length> 4.20 mm ..................................................................... 2

2. Elytron yellowish with a light brown base and apex ( Fig. 19 ), median lobe with tectum narrows to a rectangular, spatulate structure ( Fig. 21A ); Cameroon, Congo Basin towards western Uganda ( Fig. 13 ) ................................................................................................. Oosagitta geescheae sp. nov.

– Elytron unicolor pale yellowish to yellowish-brown......................................................................... 3

3. Pronotum and head dark brown, contrasting to the yellowish to yellowish-brown elytra, median lobe with incised apex, ventrally bent, elongated, slender tectum ( Fig. 7A ); widely distributed in central, east and southern Africa ( Fig. 8 )..................... Oosagitta angolensis ( Laboissière, 1939) comb. nov.

– Head, pronotum and elytra unicolorous yellowish ............................................................................ 4

4. Scapus yellowish, antennomere 2–11 brown, median lobe broad, tectum very broad at base stringly narrowed in the apical half ( Fig. 25A, B ); known from Nigeria, Congo Basin and Burundi ( Fig. 8 ) ................................................................................................................. Oosagitta thomasi sp. nov.

– Antennae yellowish throughout......................................................................................................... 5

5. Head yellow with significant postocular dark brown to black spot, ventral part of median lobe about the same length as tectum and tectorial spures ( Fig. 29 ); only knowm from to sites along the Congo River ( Fig. 8 ) .................................................................................... Oosagitta melanopicta sp. nov.

– Head yellow throughout, ventral part of median lobe much shorter than the tectm and the apically crossed tectorial spures ( Fig. 17 ); restricted to western Africa from the Ivory Coast to Togo ( Fig. 13 ) .................................................................................................. Oosagitta anningae sp. nov.

Figures

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

Figs 27-29. Oosagitta melanopicta sp. nov. 27. Habitus, semi-schematic dorsal view. 28. Basal four antennomeres of 2 ♂♂ and 2 ♀♀. 29. Median lobe. A. Dorsal. B. Lateral. Scale bars: 1 mm.

Fig. 30. Holotype of O. melanopicta sp. nov. A. Overview with labels. B. Close-up of specimen.

Figs 10-12. Oosagitta minuta comb. nov. 10. Habitus, semi-schematic dorsal view. 11. Basal four antennomeres of 2 ♂♂ and 2 ♀♀. 12. Median lobe: A. Dorsal. B. Detail: apex of endophallus. C. Lateral. Scale bars = 1 mm.

Fig. 13. Distribution of O. minuta comb. nov., O. anningae sp. nov. and O. geescheae sp. nov.

Figs 19-21. Oosagitta geescheae sp. nov. 19. Habitus, semi-schematic dorsal view. 20. Basal four antennomeres of 2 ♂♂ and 2 ♀♀. 21. Median lobe. A. Dorsal. B. Lateral. 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.

Figs 23-25. Oosagitta thomasi sp. nov. 23. Habitus, semi-schematic dorsal view. 24. Basal four antennomeres of 2 ♂♂ and 2 ♀♀. 25. Median lobe. A. Dorsal. B. Lateral. Scale bars: 1 mm.

Figs 15-17. O. anningae sp. nov. 15. Habitus, semi-schematic dorsal view. 16. Basal four antennomeres of 2 ♂♂ and 2 ♀♀. 17. Median lobe. A. Dorsal. B. Detail: apex of endophallus. C. Lateral. Scale bars: 1 mm.