Curtonotum stuckenbergi Tsacas, 1974

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, African Invertebrates 52 (2), pp. 391-391 : 438-440

publication ID	https://doi.org/ 10.5733/afin.052.0212
persistent identifier	https://treatment.plazi.org/id/03FDA115-FFFD-B362-EBDC-9F9AFB82F94C
treatment provided by	Felipe
scientific name	Curtonotum stuckenbergi Tsacas, 1974
status

Treatment

Curtonotum stuckenbergi Tsacas, 1974 View in CoL

Figs 2 View Figs 1–8 , 15 View Figs 14–26 , 28 View Figs 27–39 , 56, 59, 62 View Figs 55–63 , 80 View Figs 79–91 , 93 View Figs 92–96 Curtonotum stuckenbergi: Tsacas, 1974: 705 ; figs 2a–d (p. 707), fig. 8g (p. 718). Type locality:“ Madagascar, Ambohitantely ” .

Differential diagnosis: This species is closely related to C. keiseri , differing in the colour of the frons (yellow with indistinct vittae in C. stuckenbergi and brown with distinct vittae in C. keiseri ), the colour of flagellomere 1, and in the shape of the male terminalia. Both share the deep brown, infuscate wing membrane, the dove-tailed sternite 6, and straight, ventrally-directed lateral spine and two smaller spines on the distiphallus. Curtonotum stuckenbergi differs from C. keiseri , however, in the angle and degree of curvature of the dm–cu crossvein of the wing, in having the lateral margins of the phallus heavily-sclerotised and the smaller spines of the distiphallus positioned in the left and right lateral regions, rather than basolaterally. 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: Overall length 8 mm ( Tsacas 1974: 706); length of head and thorax combined 2.9 mm; length of thorax and scutellum combined 3.5 mm (HT); wing length 5.7 mm (n = 1, PT).

Head ( Figs 2 View Figs 1–8 , 15 View Figs 14–26 ). Eye height/length ratio: 12:8 (HT); frons ( Fig. 15 View Figs 14–26 ), frons length/ width ratio: 7:8 (HT), orbital plates extending 0.8 length of frons; posterior orbital seta moderately strong, slightly shorter than outer vertical seta; flagellomere 1 yellow pruinose basally, otherwise grey pruinose throughout, arista with 7 or 8 long dorsal branches and 3 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 weakly developed; palpus pale brown.

Thorax ( Fig. 2 View Figs 1–8 ). Mesonotum with the 2 median vittae narrow, 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 11 finer blackbrown setulae; anepisternum with 15 fine setulae, some larger and arranged in 2 groups of 2 and 3; anepimeron, laterotergite and meron silver-grey to yellow-grey pruinose; katepisternum silver-grey to yellow-grey pruinose, dorsal katepisternal seta very fine and short, ca 0.1 length of ventral katepisternal seta, with 13 short, fine setulae at base and along posterior margin.

Scutellum. As described for C. gladiiformis sp. n.

Legs. Fore coxa with 8 brown setulae on anterior surface; mid coxa with 8 brown setulae; fore tibia with ctenidium of 12 short, sharp black spinules.

Wing (as in Fig. 28 View Figs 27–39 ). Long, 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 obliquely angled and moderately straight; haltere dirty yellow.

Abdomen. Abdominal tergites as described for C. keiseri ; sternites 4–5 as described for C. coronaeformis sp. n.; sternite 6 ( Fig. 80 View Figs 79–91 ) dove-tailed (may appear narrower than Fig. 80 View Figs 79–91 in undissected specimens), markedly narrowed basally, widened laterally, with deep triangular excision apically, apical lobes squarely rounded, with dark brown maculae laterally, clothed in short, irregular brown setulae in apical ⅔, those at lateral and apical margins longer and more prominent.

Terminalia ( Figs 56, 59, 62 View Figs 55–63 ). Hypandrium ( Fig. 56 View Figs 55–63 , 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.56 View Figs 55–63 ),sclerotised area of medial lobes (viewed dorsally), with margins evenly rounded, convex medially, closely abutting, overlapping; postgonite ( Fig. 56 View Figs 55–63 , pg) long, thin and straight, with slight undulating anterior margin; epandrium ( Fig. 56 View Figs 55–63 , 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. 56 View Figs 55–63 , ce) not prominent, longest setae longer than setae on dorsal margin of epandrium; surstylus ( Fig. 56 View Figs 55–63 , ss) moderately short, widest basally, slightly curved in apical ⅔; phallus (as in Figs 59 View Figs 55–63 , ph, bp, dp, 62, bp, dp) C-shaped, heavily sclerotised, especially lateral margins of apical section of basiphallus (viewed dorsally), dark brown; phallapodeme ( Fig. 59 View Figs 55–63 , ph) fused to basiphallus, subtriangular (viewed laterally), with basal margin developed into two large, flat and broad, subtriangular projections in basal ⅔, widely bifurcated at point of connection with hypandrium; ejaculatory apodeme ( Fig. 59 View Figs 55–63 , ea) free, duct inserted at junction of phallapodeme and basiphallus; basiphallus ( Fig. 59 View Figs 55–63 , bp) broad basally and in region of first bend, then narrowed to apex, markedly narrowed in apical third (viewed dorsally); apical section ( Figs 59, 62 View Figs 55–63 , bp) very broad basally, with evenly-rounded lateral margins, sclerotised area extensive, abruptly narrowed towards apex, basal section with large membranous window, with one very strong, thick, straight, ventrally-directed lateral spine (indicated with arrow on Fig. 62 View Figs 55–63 ) and two smaller spines, positioned in left and right basolateral regions, membranous lateral extension with extensive series of small tubules.

Variation: Insufficient material is available to assess variability.

Holotype (examined): ♂ MADAGASCAR: “ Madagascar Centre / Ambohitantely 1600m / dct Ankazobe / B. Stuckenberg // 6.i.[19]58 [type-written; white paper] // HOLOTYPE [red card] // CURTONOTUM / stuckenbergi / Holotype n.sp. / L. TSACAS DET. 1973 [printed & handwritten] // MUSÉUM PARIS // Curtonotum ♂ / stuckenbergi Tsacas, 1974 / A.H. Kirk-Spriggs vidit 2008” ( MNHN). In excellent condition; re-staged on nu-poly mount; dissected, abdomen and terminalia in microvial pinned beneath specimen.

Paratype (labelled: “ Curtonotum ♂ / stuckenbergi Tsacas, 1974 / A.H. Kirk-Spriggs vidit 2008”): MADAGASCAR: 1♀ “ MADAGASCAR Tan. / Ambohitantely / 10.VI.[19] 58 F. KEISER [pink paper] // ALLOTYPE [red card] // CURTONOTUM / stuckenbergi / Allotype n.sp. / L. TSACAS DET. 1973 [printed & handwritten]” [left right wing detached and glued to card] ( NHMB) .

Note: Tsacas (1974: 706) notes “ 10v1958 ” as the date of capture of the allotype ♀; in truth the label reads “10.VI.58.”

Distribution ( Fig. 93 View Figs 92–96 ): Apparently confined to the Humid Forest vegetation type in the Central Highlands biome. In the Central biogeographical zone and Subhumid bioclimatic zone ( Figs 105–107 View Figs 105–107 ; Tables 1–3; Appendix II). The description of this species is based on two specimens collected at the same locality; one by Brian Stuckenberg in January and one by “Fred” Keiser in June 1958. “Ambohitantely” as listed on Stuckenberg’s specimen labels refers to site 7 in his unpublished report of his second Madagascan Expedition (1957–1958) (Kirk-Spriggs in press). The entry for 6 January 1958 reads: “(7) AMBOHITANTELY FOREST, ANKAZOBE DIST. – by car, approx. 120 kms. N.-W. of Tananarive, a residual patch of forest in savannah country of fair relief. Numerous small patches of forest in the vicinity suggest that the whole area was once forested and has recently been denuded. A number of peculiar species taken.”