Hemicordulia similis (Rambur)

Dijkstra, Klaas-Douwe B., 2007, Gone with the wind: westward dispersal across the Indian Ocean and island speciation in Hemicordulia dragonflies (Odonata: Corduliidae), Zootaxa 1438, pp. 27-48 : 36-37

Hemicordulia similis (Rambur)

Figs 5, 10 , 15–16 .

Cordulia similis Rambur, 1842: 147 . Holotype Ψ with labels: handwritten “ Madagascar ”, handwritten “Ramb.”, handwritten “ Cordulia similata Rb. ”, handwritten by Selys “ Hemicordulia similis , R. Ψ”, printed and handwritten by Martin “Collection Selys, Hemicordulia similis Rb. Type, Révision Martin 1906 Hemicordulia similis Rb. ”, printed red and handwritten by Martin “ Type Cordulia similis Rb. ” (ISNB) [examined].

Cordulia similata Rambur – probably Selys (in litt., see above), nomen nudum.

Cordulia ( Hemicordulia ?) similis ( Rambur, 1842) – Selys (1871: 252 (bulletin), 18 (reprint)).

Hemicordulia (?) similis ( Rambur, 1842) – Kirby (1890: 47).

Hemicordulia delicata Martin, 1896: 105 . Holotype ♂ with labels: handwritten by Martin “ Hemicordulia Séchelles. ”, “Coll. R. Martin 1920 MUSEUM PARIS” (MNHN) [ Martin (1896, 1907) did not specify the number of specimens from the Seychelles and presumably saw no females. Only this male was located in MNHN and it is assumed to be the holotype, although it bears no type labels.].

Hemicordulia similis delicata Martin, 1896 – Pinhey (1962: 208).

Further material: MADAGASCAR: 1 ď, “Madag. Schauf[uss].” ( BMNH); 2 ď, blue handwritten by Selys “Madag. Schauf[uss].”, handwritten by Selys “ Hemicordulia similis , R. ď”, printed and handwritten by Martin “Collection Selys, Hemicordulia similis Rb., Révision Martin 1906 Hemicordulia similis Rb. ” ( ISNB); 4 ď, 2 Ψ, “ Madagascar ” ( MNHN); 1 ď, 1 Ψ, Madagascar ( NMBZ); 1 ď, “E. Madagascar ” ( MNHN); 2 ď, 1 Ψ, Miarinarivo ( MNHN); 1 ď, “Tamatave”, “Madagask. Kaudern”, “ Hemicordulia similis Yngve Sjöstedt det.” ( NHRS); 3 ď, 1 Ψ, “ Madagascar ” ( RMNH); 1 ď, 1 Ψ, Tananarive, 1919, G. Waterlot ( MNHN); 1 Ψ, Ambohimangana, 4.xii.1946, leg. unknown ( BMNH); 1 ď, Tananarive, Tsimbazaza, 24.xii.1947, leg. “A.R.” ( BMNH); 3 ď, 10 km N of Tôlanaro (24°56’S 46°59’E), 17–20.iii.2004, K. Schütte ( ZMUH); 2 ď, 1 Ψ, 33 km NE of Tôlanaro (24°46’S 47°10’E), 1–3.iv.2004, K. Schütte. – SEYCHELLES: 1 ď, Mahé, slopes of Morne, xii.1952, Vesey Fitzgerald ( NMBZ).

Diagnosis. Similar to H. africana , but marginally larger on average and with darker face, perhaps slightly straighter ends of cerci ( Fig. 5 ), more triangular cleft of the vulvar scale ( Fig. 16 ) and reduced yellow at the female wing bases: almost none in Fw and at most to Cux and Ax 1 in Hw.

Remarks. Martin (1907) discussed the taxon delicata under H. similis without indicating whether it is a synonym or subspecies of the latter, but because he later omitted delicata he probably considered it a synonym ( Martin 1914). That is also how Fraser (1949) treated it, but Pinhey (1962) considered it a subspecies. Each distinct geographic area studied had its single endemic species and therefore H. s. delicata may be a separate species too. The current status is however retained because only two males were seen and no female with its potentially diagnostic vulvar scale. The unusually stalked vulvar scale, as illustrated by Fraser (1949) was only seen on the BMNH female and must be aberrant ( Fig. 15 ). All other examined females, including the type, have an unstalked scale ( Fig. 16 ).

Range and ecology. Widespread on Madagascar. Otherwise known only from Mahé, the largest of the granitic Seychelles ( Blackman & Pinhey 1967; Martin 1896), where it was recently reported from a marsh at Police Bay ( Gerlach 2003; A. Martens in litt.). Ecology unknown, but is probably similar to other species, as is the adult flight season.

Figures

FIGURES 2 – 11. 2 – 6, Male appendages of Hemicordulia species in dorsal view. (2) H. asiatica; (3) H. virens; (4) H. atrovirens n. sp.; (5) H. similis; (6) H. africana n. sp.; 7 – 11, Male appendages of Hemicordulia species in lateral view. (7) H. asiatica; (8) H. virens; (9) H. atrovirens n. sp.; (10) H. similis; (11) H. africana n. sp.

FIGURES 12 – 17. Vulvar scale and S 9 of Hemicordulia species in ventral view. (12) H. asiatica; (13) H. virens; (14) H. atrovirens n. sp.; (15) aberrant H. similis (cf. Fraser 1949); (16) typical H. similis; (17) H. africana n. sp.