Macrostemum centrotum Navás, 1917

Uy, Christine Jewel C., Malicky, Hans & Bae, Yeon Jae, 2018, Review of the filter-feeding caddisfly subfamily Macronematinae (Trichoptera: Hydropsychidae) in tropical Southeast Asia, Raffles Bulletin of Zoology 66, pp. 664-703 : 672-673

Macrostemum centrotum Navás, 1917

( Figs. 60–64 )

Macrostemum centrotum Navás, 1917: 403 [Holotype male; Vietnam ( Sapa )].

Diagnosis. Male. Antennae 30 mm in length. Antennal flagellum first few segments darker brown then lighter throughout with darker striations. Forewing 13 mm and hindwing 9 mm in length. Mesoscutum and mesoscutellum without evident markings. Tibial spurs 2.4.4.

Male genitalia. Inferior appendages two-segmented ( Fig. 61 ). In lateral view, with protrusion in phallus apex ( Fig. 63 ). In lateral view, segment X broad narrowing towards the apex ( Fig. 61 ), in dorsal view bifid and each lobe blunt ( Fig. 62 ).

Female. Antennae broken. Antennal flagellum same colouration as male. Forewing 10 mm and hindwing 7 mm in length. Mesoscutum and mesoscutellum without evident markings. Tibial spurs 2.4.4.

Material examined. Vietnam: 3 males, 4 females, Tam Dao, coll. H. Malicky, 19 May–13 June 1995 (HMPC) .

Distribution. China, Vietnam.

Remarks. The original description of Navás (1917) (in Latin) did not provide illustration, as well as information on the deposition of the specimen. The assumption is that the type specimen might be deposited in the Natural History Museum in Barcelona, Spain where his personal collections were transferred from the Catholic boy’s school (John Morse, personal communication). However, the museum curator confirmed that there are no species from the genus Macrostemum in their list of available type specimen collection by Navás (Glòria Masó Ros, personal communication). The curator also stated that there is a necessity to review the general collection and not types by Navás but the person handling the collection is now on leave. Therefore, the actual status of the type material cannot be confirmed and the possibility that it is also lost can be considered. Malicky (1998b) redescribed the male of this species including the illustrations of genitalia and forewing. The wing patterns of all the examined specimens were consistent ( Fig. 60 ).

Figures

Figs. 59–69. Macrostemum caliptera. 59, right forewing. Macrostemum centrotum. 60, right forewing; Male genitalia: 61, lateral; 62, segment X dorsal; 63, phallus lateral; 64, phallus tip. Macrostemum dairiana. 65, right forewing; Male genitalia: 66, lateral; 67, segment X dorsal; 68, phallus lateral; 69, phallus tip. Scale: 59, 60, 65 = 2 mm; 61–64, 66–69 = 0.02 mm (59 redrawn from Banks, 1931c).