Curtonotum keiseri : Tsacas 1974
Creators: name: Kirk-Spriggs, Ashley H.
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Curtonotidae
Curtonotum
Curtonotum keiseri

description: Curtonotum keiseri Tsacas, 1974   
Figs 1, 14, 27, 55, 58, 61, 79, 92  
 Curtonotum keiseri: Tsacas 1974: 706, 707 (figs 2e–f). Type locality: “ Madagascar, Joffreville ”.   
 Differential diagnosis: This species is closely related to C. stuckenbergi Tsacas, differing in the colour of the frons (brown with distinct vittae in C. keiseri and yellow with indistinct vittae in C. stuckenbergi) the colour of flagellomere 1 and the shape of the male terminalia. Both share the deep brown, infuscate wing membrane, the dove-tailed sternite 6, and the straight, ventrally-directed, lateral spine and two smaller spines on the distiphallus. Curtonotum keiseri differ from C. stuckenbergi, however, in the angle and degree of curvature of the dm–cu crossvein of the wing, in the lateral margins of the phallus being only moderately sclerotised, and in the smaller spines of the distiphallus positioned in the basolateral region, rather than the left and right lateral regions. The ranges of the two species do not overlap, and they occur allopatrically.   
Redescription:  
 Male (primarily based on field­pinned HT and PT).   
 As redescribed for C. balachowskyi, differing in the following respects: Measurements: Total length 5 mm; length of head and thorax combined 3 mm; length of thorax and scutellum combined 3 mm (n = 1, PT); wing length 3.8 mm (n = 1, N-T).   
 Head (Figs 1, 14). As described for C. gladiiformis sp. n., except: eye height/length ratio: 13:8 (n = 1, PT); frons (Fig. 14), frons length/width ratio: 6:7 (n = 1, PT), orbital plates extending 0.9 length of frons; posterior orbital seta moderately strong, slightly shorter than outer vertical seta; flagellomere 1 yellow pruinose basally and along posterior margin, dark grey pruinose centrally and on anterior margin, arista with 10 or 11 long dorsal branches and 4 ventral branches in addition to terminal fork; gena narrow, eye height/genal height ratio: 12:1 (HT), silver pruinose, slightly darker beyond basal angle; vibrissae strongly developed; palpus pale brown.   
 Thorax (Fig. 1). Mesonotum with 2 median vittae wide, 2 lateral vittae shorter, clearly defined; supra­alar seta, ca twice length of posterior dorsocentral seta; postalar setae, moderately strong, slightly exceeding length of acrostichal setae; postpronotum with 13 finer, black­brown setulae; anepisternum surface with 33 fine setulae, some larger and arranged in 2 groups of 3 and 5; anepimeron, laterotergite and meron silver-grey to yellow-grey pruinose; katepisternum silver-grey to yellow-grey pruinose, dorsal katepisternal seta ca 0.3 length of ventral katepisternal seta, with 18 short, fine setulae at base and along posterior margin.   
 Scutellum. As described for C. gladiiformis sp. n.   
 Legs. Fore coxa with 13 brown setulae on anterior surface; mid coxa with 6 brown setulae; fore tibia with ctenidium of 12–14 short, sharp, black spinules.   
 Wing (as in Fig. 27). Long and broad, tip evenly-rounded, veins chestnut-brown, membrane deep-brown infuscate throughout, darker in r 1 and anterior half of r 2+3 and in region of dm–cu crossvein; dm–cu crossvein with even arc dorsally; haltere dirty yellow.   
 Abdomen. Tergite 1 with oblique, small, subrectangular brown-black pruinose dorsolateral macula on either side and narrow medial facia; tergite 2with larger subrectangular brown-black maculae and similar medial facia; tergites 3–5 with very wide, V-shaped concolourous median fascia and large concolourous T-shaped dorsolateral macula, these fully merging with medial fascia in anterior third, lateral margin of tergites 2–5 with subelliptical, large, concolourous macula in basal half; sternites 4–5 as described for C. coronaeformis sp. n.; sternite 6 (Fig. 79) dove-tailed (may appear narrower than Fig. 79 in undissected specimens), narrowed in basal third, with deep triangular excision apically, apical lobes evenly rounded, with dark brown maculae laterally, clothed in short, black, irregular, brown setulae in apical ⅔, those at lateral and apical margins longer and more prominent.   
 Terminalia (Figs 55, 58, 61). Hypandrium (Fig. 55, hy) long, with broad-based rounded-truncate dorsobasal lobe, posterior bridge dorsally and ventrally produced (subtriangular to slightly angulate in profile); hypandrial arm constricted medially (viewed laterally), with 2 parallel setulae proximal to postgonite, of similar length (obscured by epandrium on Fig. 55), sclerotised area of medial lobes (viewed dorsally), with margins evenly rounded, convex medially, closely abutting, overlapping; postgonite (Fig. 55, pg) long, thin and straight, with slight undulating anterior margin; epandrium (Fig. 55, ep) slightly broader dorsally than ventrally (viewed laterally), evenly rounded on dorsal margin, posterior margin slightly angled, ventral margin with extensive row of long, regular to irregular, apically-directed setae; cercus (Fig. 55, ce) not prominent, longest setae longer than setae on dorsal margin of epandrium; surstylus (Fig. 55, ss) long, widest basally, slightly curved in apical ⅔; phallus (as in Figs 58, ph, bp, dp, 61, bp, dp) C-shaped, moderately sclerotised, brown; phallapodeme (Fig. 58, ph) fused to basiphallus, subtriangular (viewed laterally), with basal margin developed into two flat, broad, subtriangular projections in basal fifth, bifurcated at point of connection with hypandrium; ejaculatory apodeme (Fig. 58, ea) free, duct inserted at junction of phallapodeme and basiphallus (missing from specimens illustrated in Fig. 58); basiphallus (Fig. 58, bp) broad basally and in region of first bend, then narrowed to apex, markedly narrowed in apical third (viewed dorsally); apical section (Figs 58, 61, bp) broad basally, sclerotised area extensive, abruptly narrowed towards apex, basal section with membranous window, with one narrow, but strong, straight, ventrally directed lateral spine (arrowed on Fig. 61) and two smaller spines, positioned in basolateral region, left margin of sclerotised area with irregular row of small tubules.   
Variation: Insufficient material is available to assess variability.  
 Holotype (examined): ♂ MADAGASCAR: “ MADAGASCAR.D.­S. / Joffreville / 25.V.[19] 58 F. KEISER [pink paper] // HOLOTYPE [red card] // CURTONOTUM / keiseri n.sp. / Holotype / L. TSACAS DET. 1973 [printed & handwritten] // BM [handwritten] // MUSÉUM PARIS // Curtonotum / keiseri ♂ / Tsacas, 1974 / A.H. Kirk-Spriggs vidit 2006” [head missing] (MNHN). In poor condition, head and all legs except left fore femur, fore tibia, left hind femur and hind tibia missing; direct-pinned; dissected, abdomen and terminalia in micro-vial pinned beneath specimen.   
 Paratype: ♂ “ MADAGASCAR.D.­S. / Mtge. D’Ambre [= Montagne d’Ambre] / 24.V.[19] 58 F. KEISER [pink paper] // PARATYPE [red card] // CURTONOTUM / keiseri n.sp. / paratype / L. TSACAS DET. 1973 [printed & handwritten] // Curtonotum / keiseri ♂ / Tsacas, 1974 / A.H. Kirk­Spriggs vidit 2008” (NHMB). Other material examined (labelled: “ Curtonotum keiseri Tsacas, 1974 ♂ det. A.H. Kirk­Spriggs 2011”): MADAGASCAR: 1♂ Madagascar N., Ambohitra, Joffreville, 800 m, 9–12.iv.1991, A. Freidberg & Fini Kaplan [left wing detached and glued to card] (TAU).   
Distribution (Fig. 92): Apparently confined to the Humid Forest vegetation type in the Evergreen Rainforest biome. In the North biogeographical zone and Dry bioclimatic zone (Figs 105–107; Tables 1–3; Appendix II).
description: Published as part of Kirk-Spriggs, Ashley H., 2011, A revision of Afrotropical Quasimodo flies (Diptera: Schizophora; Curtonotidae). Part III - the Malagasy species of Curtonotum Macquart, with descriptions of six new species, pp. 391 in African Invertebrates 52 (2) on pages 419-422, DOI: 10.5733/afin.052.0212, http://zenodo.org/record/8342930