Etrocorema belumensis Wan Nur Asiah & Che Salmah, 2009

Asiah, Wan Nur, W. M., Salmah, M. R. Che & Sivec, Ignac, 2009, Description Of Etrocorema Belumensis Sp. N. From Royal Belum State Park, Perak, Malaysia, Illiesia 5 (17), pp. 182-187 : 184-186

Etrocorema belumensis Wan Nur Asiah & Che Salmah sp. n.

( Figs. 1-10 )

Etrocorema sp. : Uchida and Yamasaki, 1989:136. Fig. 2 .

Material examined. Holotype ♂, 3♀ paratypes: Malaysia: Perak, Belum State Park. 20-25 April 2009, light trap. (Deposited at School of Biological Sciences, Universiti Sains Malaysia – SBC, USM). Additional paratypes: 2♂, 2♀, Perak, Belum expedition base camp. 5°30’07’’N, 101°26’21’’E, III- VII. 1994. Light trap. (Deposited at Slovenian Museum of Natural History , Ljubljana).

Adult habitus. Biocellate, general color dark brown. Mid size to large species, forewing length 12.5 mm in male and 18.0 mm in female. Head with large quadrangular dark brown pattern reaching the front of M-line. M-line and tentorial calluses conspicuous ( Fig. 1 ). First two segments of antennae pale, remaining segments dark brown. Palpi brown. Mesal occipital knob present. Distance between ocelli about two diameters to the eye margin. Pronotum brown, nearly as wide as head, with slightly paler rougosities. Distal part of femora dark brown. Forelegs uniformly dark brown, mid and hindlegs darker only at distal end. Ventral side of cerci with a row comprised of a single strong and long spine on each segment.

Male. Terminalia generally similar to E. nigrogeniculatum ( Fig. 2 ). Metasternum and sternum 6 with strong hair brushes. Penis generally similar to E. nigrogeniculatum , differing in a longer triangular field of fine spicules on ventral side of penis sac, reaching nearly to base of sac ( Fig. 3 ). Apex of extended penis sac with 4 rounded lobes.

Female. The large, expanded subgenital plate is similar to E. nigrogeniculatum , but differs in a deeper median notch, nearly one third the length of subgenital plate ( Fig. 4 ). Vagina generally similar to the structure of E. nigrogeniculatum ( Fig. 5 ).

Egg. The “drop- shape” of eggs ( Fig. 2 of Uchida and Yamasaki, 1989) is different from the oval eggs of E. nigrogeniculatum (compare Fig. 8 and Fig. 11 ). Length of egg ca 0.41 mm and slightly larger than E. nigrogeniculatum eggs collected from the same locality. Short ring like collar ( Fig. 9 ) wider than the collar of E. nigrogeniculatum egg. Chorion with rounded shallow pits that are bigger and oval near the collar ( Figs. 8-10 ). A few micropyles located in the middle of egg ( Fig. 8 ). Anchor pedicel short ( Fig. 9 ).

Larva. General habitus ( Fig. 7 ) corresponds to E. nigrogeniculatum larva. The only apparent difference is the presence of a pale area behind the compound eyes on the occipital part of the head ( Figs. 6-7 ). This difference was observed only in mature larvae. Among smaller size larvae we could not recognize this color pattern. As we have no larval material from throughout the year, we do not know if smaller larvae were present during the December-May study period, or if it is possible to separate early instars of the two species.

Etymology. Species is named for the royal Belum State Park, Perak, Malaysia.

Remarks. Our investigation in the Belum area showed the presence of closely related but distinct species of this genus which we describe herein. The previous concept of single variable Etrocorema species throughout South East Asia should be reevaluated by more detailed study of species in current synonymy and in study of material from throughout Southeast Asia. Collections are also needed from Hainan Island in order to evaluate the status of E. hochii .

Figures

Figs. 1-5. Etrocorema belumensis. 1. Head and pronotum, 2. Male terminalia, dorsal, 3 Aedeagus lateral, 4. Female terminalia, 5. Vagina lateral and ventral view.

Figs. 6. Etrocorema belumensis. Larva, habitus.

Figs. 7. Etrocorema belumensis. Head and pronotum of larva.

Figs. 8-13. Etrocorema belumensis. 8. Egg, 9. Egg collar, 10. Micropyle and chorionic detail. Etrocorema nigrogeniculatum. 11. Egg, 12. Egg collar, 13. Micropyle and polar chorionic detail.