Revision of the Oriental Genus Odontoptilum De Nicéville (Lepidoptera: Hesperiidae: Pyrginae)
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Rienk de JONG National Museum of Natural History, Leiden REVISION OF THE ORIENTAL GENUS ODONTOPTILUM DE NICÉVILLE (LEPIDOPTERA: HESPERIIDAE: PYRGINAE) Jong, R. de, 2006. Revision of the Oriental genus Odontoptilum de Nicéville (Lepidoptera: Hesperiidae: Pyrginae). – Tijdschrift voor Entomologie 149: 145-159, figs. 1-54. [issn 0040- 7496]. Published 1 December 2006. The Oriental genus Odontoptilum, currently conceived as consisting of three species and five additional subspecies, is revised based on examination of all types and a study of recent material, particularly from the Philippines. As a consequence the number of species-group taxa is raised to ten, arranged in two genera (one new, Semperium for the species Pterygospidea leptogramma Hewitson, 1868), six species and four additional subspecies. Two species, O. corria sp. n. and O. abbreviata sp. n., and one subspecies, O. pygela tawita ssp. n., are described for the first time, and one species, O. helias (Felder & Felder), is raised from subspecies rank. O. angulata sinka Evans proved to be a junior synonym of O. helias helisa Semper. Four species are restricted to Wallacea. The genera are remarkable because of the strongly asymmetrical genitalia and the occurrence of three types of secondary sexual characters, one of which is described for the first time. R. de Jong, National Museum of Natural History, P.O. Box 9517, 2300 RA Leiden, The Netherlands. E-mail: [email protected] Key words. – Hesperiidae; Odontoptilum; Semperium; secondary sexual characters; new taxa; taxonomy; distribution; Oriental region; Wallacea. The genus Odontoptilum as currently understood in Odontoptilum and that its isolated taxonomic posi- (Evans 1949, Maruyama 1991, Eliot 1992, Bridges tion is best reflected by placement in a new genus. 1994) contains three species: O. angulata (Felder, All taxa are briefly described below to facilitate 1862), from Sri Lanka and NW Himalayas to the identification, and relevant characters are illustrated. Philippines, Sulawesi and the Lesser Sunda Islands, For synonymy other than proposed here, see Evans O. pygela (Hewitson, 1868) from Burma and Thai- (1949). All holotypes relating to species-group names land to Java and Borneo, and just penetrating the in Odontoptilum are in the Natural History Museum, Philippines, and O. leptogramma (Hewitson, 1868), London (bmnh), except one that is in Forschungsin- endemic to the Philippines. The species are easy to stitut und Naturmuseum Senckenberg, Frankfurt- separate on the basis of external characters. In the am-Main (smf), and the types of the newly described male genitalia O. leptogramma stands apart because of taxa, which are in the National Museum of Natural the elaborate valvae, while the valvae of O. pygela and History ‘Naturalis’ (formerly Rijksmuseum van O. angulata are of a simple and much more slender Natuurlijke History), Leiden (rmnh), and in the col- build. While O. leptogramma and O. pygela exhibit lection of C.G. Treadaway (cgt, donated to smf). minor variation, O. angulata (as conceived by Evans 1949) is highly variable, seasonally as well as geo- Odontoptilum in relation to other genera graphically, and in wing markings as well as in geni- talia. This variation, displayed by a richer material The Oriental genus Odontoptilum de Nicéville, than Evans (1949) had at his disposal, prompted re- 1890, as currently conceived, belongs to a group examination of the types and, subsequently, a revision of Afro-Oriental genera described as the Tagiades of the concept of O. angulata. Further, examination group by Evans (1949), a grouping that, on the ba- of the genitalia and secondary sexual characters led sis of molecular data, may well be monophyletic to the conclusion that O. leptogramma was misplaced (A. Warren pers. comm.). Within the Tagiades group, 145 Downloaded from Brill.com09/27/2021 09:27:07AM via free access T E, 149, 2006 1 2 3 Figs. 1-3. Venation and outline of hindwing of Semperium leptogramma (1), Odontoptilum pygela (2), and O. helias (3). The other Odontoptilum species have an outline similar to O. helias. Odontoptilum shares three characters with the genera species are described and figured for the first time, the Ctenoptilum de Nicéville, 1890 (Oriental), Caprona position of O. leptogramma (Hewitson) is reconsid- Wallengren, 1857 (Afro-Oriental; the congenerity ered, O. pygela (Hewitson) is briefly described (and of the Oriental and African species needs re-exami- a new subspecies is proposed), and a taxonomic revi- nation), Netrobalane Mabille, 1904, Leucochitonea sion of the O. angulata (Felder) complex is presented, Wallengren, 1857, and Abantis Hopffer, 1855 (the including the description of two new taxa. latter three genera restricted to the Afrotropics). Evans (1949) coined the name Caprona subgroup for these Delimitation of Odontoptilum genera. The characters which more or less separate them from the other genera of the Tagiades group are: The type species of Odontoptilum is O. angulata antennal apiculus blunt, subcostal vein of forewing (Felder, 1862). The genus is currently conceived as ending well before end of cell, and the male genitalia containing three species, O. angulata, O. pygela, and asymmetrical to some extent, in the valvae as well as O. leptogramma. According to Evans (1949), they in the uncus and gnathos, with the aedeagus generally share the following characters that separate them emerging from the right. Asymmetrical male genitalia from the genus Caprona: (1) hair pencil on fore coxae are not unique among Hesperiidae (see for example, of male short (long in Caprona and Leucochitonea); Burns 1964), but they are among the Tagiades group (2) tegulae of male more or less prolonged; (3) tor- (with exception of the genus Abraximorpha Elwes & nal cilia of hindwing elongate. However, the tegu- Edwards, 1897, which in other characters appears to lae of the male are also longer than in the female in be more closely related to other genera). Whether Caprona agama Moore, 1857 (Oriental region) and these characters point to a closer relationship be- in C. pillaana Wallengren, 1857 (Afrotropical re- tween, and monophyly of, the six genera remains to gion), and possibly in more species which have not be studied. There are other remarkable characters that been checked. Elongate tornal cilia on the hindwing seem to point in the same direction. One character can also be found, within the Caprona subgroup, in is the irregular outline of the wings (figs. 1-3) (but the Afrotropical genera Netrobalane and Abantis (at regular in Leucochitonea and Abantis), not unique in least in some of the species), and also in other genera the Tagiades group, but rarely found to this extent. of the Tagiades group like the Oriental genera Darpa Caprona, Leucochitonea and Odontoptilum share a Moore, 1865, and Seseria Matsumura, 1920. Hence peculiar and unique sexual character in the male, a the morphological basis for considering the three dense hair tuft on the fore coxae. Ctenoptilum has a species congeneric (i.e. more closely related to each recumbent hair pencil on the hind tibiae in the male, other than to any other species) is very weak indeed, a character widespread among Pyrginae, but absent in viz. the length of the hair pencil on the fore coxae many genera and, although of diagnostic value, ap- of the male. However, I failed to find the hair pencil parently of little help in establishing relationships. on the fore coxae of O. leptogramma. Moreover, while In this study a novel secondary sexual charac- the male genitalia of O. angulata and O. pygela are of ter is described and figured, female genitalia of the similar build, those of O. leptogramma are abundantly 146 Downloaded from Brill.com09/27/2021 09:27:07AM via free access de Jng: Revision of Odontoptilum different (valvae complicated, uncus with large dorsal Semperium gen. n. horn, no gnathos), negating the reason for considering Type species (and sole species included): Pterygospidea O. leptogramma more closely related to O. angulata leptogramma Hewitson, 1868. and O. pygela than to any other species. In addition, O. leptogramma proved to have a unique secondary Description. − See S. leptogramma. See also above, sexual character. The isolated taxonomic position of under Delimitation of Odontoptilum. O. leptogramma in the Caprona subgroup is best re- Etymology. − The genus is named after Georg flected by placing the species in a genus of its own Semper (1837-1909), the Nestor of Philippine lepi- with, as yet, unclear relationships. Therefore, a new dopterology. genus is described below. Semperium leptogramma (Hewitson) Secondary sexual characters in Odontoptilum Pterygospidea leptogramma Hewitson, 1868: 53. Holotype In Hesperiidae, secondary sexual characters (sscs) , in bmnh; type locality: Philippines. are characters, other than genitalic characters, that presumably play a role in sexual behaviour by scent Material examined. − Holotype , Philippines emission. They are widespread in Hesperiidae, par- (bmnh); 41, 6, Cebu, Leyte, Luzon, Mindanao, ticularly in the male, but scent distributing organs Mindoro, Samar, Sibuyan (bmnh, cgt, rmnh). in females have been described as well (Burns 1964, de Jong 1975). A common feature among females External characters (figs. 37, 40). − Length in the Tagiades group, and found in all species of of forewing, male 18.9-20.0 mm, female 20.2- Odontoptilum and the new genus Semperium, is the 20.6 mm. Upperside forewing with a fuzzy whitish- presence of thickly packed, wavy, hairlike scales at violet line from mid-dorsum to mid-costa, a narrow, the tip of the abdomen, known as ‘anal wool’. It is broken white line crossing space 1bc and space 2 (ap- reminiscent of a ssc but as described by Igarashi & parently the median spots in these spaces) and fol- Fukuda (1997) for several Tagiades species and by lowing the discoidal veins, a fuzzy violet zigzag line Bascombe et al. (1999) for O. angulata, its function is between the latter line and the outer margin, a short not in sexual behaviour: the hairs are used to conceal bluish line near the base from dorsum to cubital vein the laid eggs.