Hyriopsis delaportei (Crosse & Fischer, 1876) Fig. 3F

Unio (Arconaia) delaportei Crosse & Fischer, 1876: 327-329, pl. 10, fig. 1, pl. 11, fig. 5. Type locality: "Cambodge, dans la province de Compong-Soai".

Hyriopsis (Hyriopsis) delaportei: Brandt 1974: 273-274, pl. 21, fig. 37.

Material examined.

CIFI.MOL.025, CIFI.MOL.026, MUMNH.UNI.2623, MUMNH.UNI.2628, MUMNH.UNI.2631, MUMNH.UNI.2653, ZRC.MOL.015645.

Distribution and habitat.

Tonle Sap Lake at Kampong Chhnang, Kampong Thom, Pursat and Siem Reap Provinces (locality no. 11, 16, 37 and 38); in soft muddy substrate.

Remarks.

Not sold for food, collected as by-catch of Corbicula and Mekongia harvests, and were often observed to be discarded along with other large unionids. Shells of Hyriopsis delaportei were also found to be covered in mats of Limnoperna fortunei and Sinomytilus harmandi . Hyriopsis delaportei was originally described from "Compong Soai; Cambodia" (Morlet 1889). It is abundant in the Tonle Sap Lake and its tributaries. The distribution range outside the country is in Vietnam in the Mekong River delta at An Giang, close to the border with Cambodia (Bogan and Do 2014), and in Thailand at the Satung River, Srakaeo and Kaek River, Pitsanulok, although the latter record remains uncertain (Brandt 1974).