DYSPHANIINI + XENOZANCLA + PSEUDOTERPNINI S. S.

In this study, the grouping of Dysphaniini, Xenozancla and Pseudoterpnini s.s. is fully supported in Bayesian analyses but only weakly supported in ML analyses, with Dysphaniini constituting a sister-group of Xenozancla + Pseudoterpnini.

The Dysphaniini currently includes only two known genera, Dysphania Hübner and Cusuma Moore, which have been regarded as a natural group. Warren (1895) treated the Dysphaniini as the subfamily Dysphaniinae. Prout (1912) put Dysphania and Cusuma into Group III of Old World genera. Both treatments reflect the distinctive characters that these genera possess. Holloway (1996) presented the unique features of Dysphaniini (the presence of a forewing fovea in both sexes, ansa hammer-headed and lacking a central expansion) in detail and treated it as a sister-group to the rest of Geometrinae. Our result is almost concordant with Sihvonen et al. (2011), in that we did not find support for a division between Dysphaniini and the remaining Geometrinae. The difference from Sihvonen et al. (2011) is that the sister relationship between Dysphaniini and Pseudoterpnini is not supported. Instead, Xenozancla is clustered with Pseudoterpnini.

Xenozancla is a small Asian genus that includes only one species. It has not been placed into any known tribes because its combined external and male genitalic features (small size, concavity of forewing distal margin under apex, the coexistence of a bifid uncus and socii, simple valva and long saccus) do not agree with those of known tribes (Han & Xue, 2011a). The present position of Xenozancla is doubtful, given its morphology. Xenozancla is morphologically similar to some species of Pelagodes in Thalassoditi, as the socii of the male genitalia are attached to the base of the gnathos (Han & Xue, 2011a: fig. 390; Han & Xue, 2011b: figs 33–34.). Prout (1912) mentioned its affinity with the African genus Bathycolpodes Prout; both genera have an anteriorly excavated distal margin of the forewing and almost identical wing patterns. In Xenozancla, the excavation on the hindwing is shallower than in Bathycolpodes.

Pitkin et al. (2007) provided a comprehensive morphological review of the tribe Pseudoterpnini, in which 34 genera were recognized, covering most genera in the Pseudoterpninae (Warren, 1893, 1894), Groups I and II (Prout, 1912), Terpnini (Inoue, 1961), Archaeobalbini (Viidalepp, 1981), Pingasini (Heppner & Inoue, 1992), Pseudoterpnini (Hausmann, 1996, 2001) and Pseudoterpniti (Holloway, 1996). They suggested that Pseudoterpnini was likely monophyletic, although no single defining character was found.

Hausmann (1996, 2001) stated that some features of Holoterpna Püngeler and Aplasta Hübner were anomalous within Pseudoterpnini, the systematic position of Aplasta being particularly isolated. When Holloway (1996) summarized the diagnosis of Pseudoterpnini, he also mentioned that the strong black discal dots and broad black bands on the underside, characteristic of most genera in this broad concept, are absent from Pseudoterpna (though present in Pingasa). Pitkin et al. (2007) also referred to the fact that the type genus Pseudoterpna and several apparently related genera (Aplasta, Holoterpna, Mictoschema Prout and Mimandria Warren) are anomalous in comparison with the rest of the tribe. All these statements imply that the monophyly of Pseudoterpnini is in doubt.

In this study, it is surprising that most Oriental and Palaearctic Pseudoterpnini genera in Pitkin et al. (2007), such as Herochroma, Metallolophia, Actenochroma, Absala, Metaterpna, Psilotagma, Limbatochlamys, Dindica, Dindicodes, Lophophelma and Pachyodes, are not clustered with the type genus of Pseudoterpnini, Pseudoterpna. This result differs from other research, such as Sihvonen et al. (2011), in which only two genera and two species of Pseudoterpnini, Pseudoterpna coronillaria (Hübner) and Crypsiphona ocultaria (Donovan), were sampled. This result probably further proves that the monophyly of the tribe Pseudoterpnini is problematic. We tentatively treat the concept of Pseudoterpnini of Pitkin et al. (2007) as Pseudoterpnini s.l. and genera centred around Pseudoterpna as Pseudoterpnini s.s.

Prout (1912–16) stated that the larva of Pingasa seems to be allied with Pseudoterpna and that the latter is probably descended from the former. In this study, Pseudoterpna and Pingasa form a monophyletic clade representing Pseudoterpnini s.s. with full support, validating the close relationship mentioned by Prout. These genera also share a similar wing pattern (distinctive transverse lines) and male genitalia (e.g. bifid socii) with Epipristis Meyrick, Mictoschema, Mimandria, Hypodoxa Prout and Pullichroma Holloway. However, to determine which genera belong to Pseudoterpnini s.s., a more extensive phylogenetic study including all the related genera in Pseudoterpnini s.l. and not only Oriental genera, as in this study, is needed.