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Bertula
Walker
Type species:
abjudicalis
Walker, Sri Lanka.
Synonyms: Cardalena Walker (replacement name for Neviasca Walker); Elyra Walker (type species phlegeusalis Walker, Borneo) syn. n.; Eordaea Walker (type species peleusalis Walker = phlegeusalis) syn. n.; Gabrisa Walker (unnecessary replacement name for Neviasca); Neviasca Walker (type species tespisalis Walker), praeocc.
The type species of Elyra (and its synonym Eordaea) are related through facies similarities to Bertula alpheusalis Walker (see below and Owada (1992: 185)). Bertula has page priority over Elyra. The type species of both genera fall within the broad concept adopted here, as does the manuscript name Thysanognatha Hampson (Nye, 1975: 483) which is associated with alpheusalis in BMNH. However, the bipectinate male antennae and the lack of a foretarsal spur in the Elyra group are atypical of Bertula (see below).
The inclusion of a number of Oriental species in the New World genus Bleptina Guenée (listed by Poole (1989)) is unjustifiable, as there is no obvious relationship. Those discussed below relate more to Bertula and allies, and share some facies elements with species such as B. crucialis Felder & Rogenhofer and B. delosticha Swinhoe. They are therefore placed in Bertula. Owada (1987) transferred Japanese species to Bertula from the concept of Bleptina applied to the Oriental fauna at the end of the 19th Century by, for example, Hampson and Leech. Owada (in Inoue et al., 1982) was the first to state that all such Oriental species are better placed in Bertula.
These Oriental ‘Bleptina’ mostly have pale linear fasciation and a pale discal lunule to both surfaces of the forewing, together with a pale submarginal zone near the apex of the wing similar to that of Adrapsa Walker. However, they resemble Bertula and allies by having a dark discal lunule and orbicular spot close together on the hindwing underside, rather than just a discal lunule (which is frequently pale). The labial palps of males are strongly recurved, with the apex of the third segment extending beyond the anterior margin of the thorax as in Bertula and allies.
In Bertula generally, the male antennae are various, usually ciliate or fasciculate, but sometimes bipectinate (e.g. the Elyra Walker group). The labial palps are typically strongly recurved back over the head to the centre of the thorax, and often have a brush of hair-scales on the third segment. The foreleg has a sheath from the tibia over the tarsal segments and may also enclose a hair-pencil. Owada (1987) noted a process at the distal end of the first tarsal segment in Japanese species as discussed on p. 20. A sample of species from across the genus was found mostly to have this feature, though it was absent from B. crucialis Felder & Rogenhofer B. delosticha Swinhoe, B. micropulla sp. n., the Elyra group of species (see above) and from “B. ” postlineata sp. n. It occurs also in the next two genera, in Egnasides Hampson and in Hepsidera Swinhoe. It is most strongly developed in B. picta Pagenstecher.
The facies is diverse, but the forewing usually has strong antemedial and postmedial fasciae that enclose a paler medial zone amid a generally dark brown ground. In a number of species these fasciae are relatively straight, cream or white, with the medial zone as dark as the portions on either side of the fasciae. In others the postmedial is straighter, doubled, enclosing a bluish or mauvish band. However, the type species and those treated up to microdepressalis sp. n. have the typical pale medial zone with the postmedial oblique, sinuous to stepped centrally. The hindwing is usually dark as in the forewing, with paler postmedial and submarginal fasciae that run more or less parallel to each other from the dorsum, fading away anteriorly; the submarginal is generally irregular, rather than obtusely angled. On the underside, an unusual feature is the very frequent occurrence of a dark orbicular spot interior to the discal mark. This feature is seen also in the next few genera, but is absent elsewhere in the herminiines apart from in Subsimplicia reniformis sp. n.. It is probably the most reliable feature for distinguishing the rather broad concept of Bertula adopted here, in conjunction with facies features (see also the next two genera).
In the male abdomen, the eighth segment is unmodified, though the tergite has short, widely separated apodemes. The genitalia have diverse features but usually the uncus is rather bulbous, and the saccus is well developed. The valves show great diversity. The aedeagus vesica is large, extending at a right angle from the axis of the aedeagus, and with varying degrees of scobination. Larger cornuti are present in a few instances, and the aedeagus apex itself can be ornamented.
The female genitalia also show variety, though not all species were dissected. The corpus bursae is sometimes scobinate generally, or sometimes this is concentrated into one or two signa. In a few species there is a small spine in a relatively distal position in place of a signum, and one group has a transverse ridge or fold of sclerotisation centrally. The ductus seminalis usually originates between one-third to centrally on the bursa, but is always basal to any signa.
Poole (1989) listed Bertula syrichtusalis Walker still as a valid species in the genus, with Borneo as type locality, but the species is in fact an epipaschiine pyralid, Salma syrichtusalis, illustrated by Robinson et al. (1994: Plate 24). Poole also stated that the type of syrichtusalis was in BMNH, whereas in fact it is in Oxford (OUMNH: type 857).
The genus has numerous species in the Oriental tropics and subtropics, but only a few species occur east of Sulawesi.
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