Baroa siamica Hampson

Baroa siamica Hampson, 1911, Ann. Mag. nat. Hist. (8), 8: 411.

Baroa soricina javanica Kalis, 1934, Ent. Rundsch. 51: 209.

Baroa javanica Rothschild, 1935, Novit. Zool., 39: 250 (junior primary homonym).

Baroa siamica Hampson; Holloway, 1976: 4.

Diagnosis

The dark brownish grey, narrow forewings, blackish hindwings and speckled, bright yellow thorax distinguish this species. The male has the hind-wing dorsum much expanded, folded, paler, inverted with scent scales. Taxonomic notes. B. soricina Snellen (Sulawesi) is sister-species to siamica. It is likely that the Kalis and Rothschild taxa are the same as the latter based his description on material collected in Java by the former. There are minor genitalic differences in material from Thailand, Borneo and Java, though externally the moths are indistinguishable. Typical siamica has much broader signa bands in the bursa copulatrix than do the females from the other three localities. Javan males have the uncus processes slightly out curved and bearing a few stout, spinelike setae apically that are not seen in Bornean material.

Geographical range

Thailand, Sundaland, Philippines.

Habitat preference

On G. Kinabalu records were made from 1200m to 1930m. Most records on G. Mulu were from lower montane forest at 1000m where the species was common, though it was also recorded in lowland dipterocarp forest on both G. Mulu and G. Api. Records from Brunei have been from lowland forest, and also upper montane forest at about 1700m (Bukit Retak, Bukit Pagon).

Taxonomic Note

As indicated in Part 6, on p. 372 and in the previous Note, the placement of the genus Baroa in the Arctiinae has long been open to question. Preliminary analyses of a larger sample of taxa (Zahiri et al., in preparation) following that of Zahiri et al. (2011) have included a specimen of B. siamica, and this was placed within the Nolidae but with no strong indication of subfamily. The larval features described below are unusual and intermediate between those of the Nolinae and other groups. The genus Baroa Moore is therefore transferred to Nolidae with uncertain status. Cerný (2011) described a new subspecies of siamica, maramaga Cerný, from Mindanao in the Philippines but noted the typical race in Luzon. He recorded three species endemic to the archipelago, two described as new. A final instar larva of B. siamica, feeding on Vernonia arborea (Compositae), was reared through in Peninsular Malaysia (H.S. Barlow & S.K.L. Hok, pers. comm.). It is illustrated in Plate 10. All prolegs are fully developed. There is some development of secondary setae on verrucae, particularly on the thoracic

Genitalia: