Metaemene atrigutta Walker

Lyclene atrigutta Walker, 1862, J. Proc. Linn. Soc. (Zool.), 6: 116.

Siccia maculata Leech, 1888, Proc. zool. Soc. Lond., 1888: 605.

Metaemene atrigutta ab. annuligera Warren, 1913, Gross-Schmett. Erde, 11: 297.

Metaemene atrigutta ab. confluens Warren, 1913, Gross-Schmett. Erde, 11: 297.

Metaemene atrigutta ab. annuligera Strand, 1917, Arch. Naturgesch., (82A) 2: 37.

Metaemene atrigutta ab. reducta Strand, 1917, Arch. Naturgesch., (82A) 2: 36.

[Metaemene atrigutta ab. derufata Warren, 1913, Gross-Schmett. Erde, 11: 297.]

[Metaemene atrigutta ab. metaemenides Strand, 1917, Arch. Naturgesch., (82A) 2: 36.]

Diagnosis

This is the smallest species of the atrigutta group, with the forewings entirely pale rufous brown apart from the black dots that may have a slightly paler halo. The hindwings are a uniform pale brown. The male genitalia have a distinctive valve where the central process is broad, tongue-like (somewhat produced dorsally in more easterly material), with a small lateral lobe on its ventral margin just distal to the base of the saccular process. The processes of the tegumen are as described under the next species, but relatively short, the more ventral one usually shorter, sometimes rather stout. The aedeagus vesica has a simple, tongue-like sclerite. In the female genitalia, the pouches on each side of the ostium are relatively shallow and simple, and the neck of the corpus bursae has only a small sclerite within it, also obtusely angled in lateral view.

Taxonomic note

Nye (1975) indicated that the type material of atrigutta was in BMNH, and indeed there is a specimen from Sarawak collected by A.R. Wallace that bears a green Walker type label. However, Hampson (1910) listed this specimen without flagging it as a type, and both Swinhoe (1892) and Lansbury (1970 catalogue, unpublished) listed the type as being in Oxford (OUMNH); it bears the number 1578 and is so listed by Lansbury. The specimen illustrated by Hampson (1910) accords with the OUMNH one in facies better than with the BMNH one. The BMNH specimen is probably therefore mislabelled as type or is a syntype, but, to avoid future confusion, the OUMNH specimen, a male, is hereby designated LECTOTYPE. It has been dissected and has genitalia as described and illustrated here.

Hampson (1910) listed maculata (see above) as an ‘ab.’ of atrigutta, and also three other ‘ab.’ categories numbered 1-3. The specimens concerned were given names by both Warren and Strand as indicated above (both authors named one of these as annuligera). The specimen named ab. derufata by Warren was renamed ab. metaemenides by Strand and is a distinct, more or less white species with black dots that occurs in Java; this is referred to in the description of albigrisea above. The status of the taxa yakushimaensis Miyake and okinawana Matsumura from the southern archipelagoes of Japan has not been investigated. There is a species in Sulawesi with very similar male and female genitalia (slides 20395, 21330) to atrigutta, but with the forewing pink area restricted to basal, antemedial and postmedial bands by extensive white areas surrounding the black dots and extending broadly along the costal and distal margins. It is possible also that there may be a complex of species with the typical facies type in the eastern part of the range, as preliminary DNA barcoding results point in this direction (S.E. Miller, pers. comm.). The sample assessed at the time of writing is small, but the most distinctive barcode grouping can also be recognised on morphological grounds in that the central process of the valve is elongated and has a somewhat quadrate apex. This taxon has been recorded through the New Guinea archipelago from Waigeu in the west (slide 21346) through Madang Province (USNM slide 125627) to Misima I. (barcode data) in the Louisiade Archipelago.

Geographical range

Japan, China, Taiwan, Nicobar Is., Peninsular Malaysia, Singapore, Borneo, Philippines, Moluccas, New Guinea, Admiralty Is.

Habitat preference

All Bornean material seen is from lowland localities (Sarawak ex Wallace, including the syntypes, Pulo Laut), but is without precise data. The species may prove to be commoner on coasts and islands.