During recent survey work and examination of museum collections in Hanoi, we became aware that a species misidentified in the literature was in fact a new and rare species of freshwater bivalve. It is currently known only from 12 dry valves in the collections in Hanoi, Vietnam and 2 valves in the North Carolina Museum Collection. These specimens resemble the eastern Chinese genus Pseudobaphia Simpson, 1900. We describe these specimens from the Bằng River, Cao Bằng Province, Vietnam as a new species: Pseudobaphia banggiangensis new species.

During recent survey work and examination of museum collections in Hanoi, we became aware that a species misidentified in the literature was in fact a new and rare species of freshwater bivalve. It is currently known only from 12 dry valves in the collections in Hanoi, Vietnam and 2 valves in the North Carolina Museum Collection. These specimens resemble the eastern Chinese genus Pseudobaphia Simpson, 1900. We describe these specimens from the BằngRiver, Cao BằngProvince, Vietnam as a new species: Pseudobaphia banggiangensis new species.

The semi-slugs seem to be quite common at the locations where they have been observed. This species is presumed to have been recently introduced since it is very unlikely that a relatively large and apparently locally common species has been overlooked in previous studies on terrestrial molluscs in Singapore (e.g., Lim, 1969; Ho, 1995; Tan et al., 2012). More surveys are needed to determine if these slugs have become common and widespread in other parts of the island. It is thus hoped that readers will come forward with information if they encounter this semi-slug, which can be recognised by its ‘rough’ (tubercles all over the dorsal part of its body except its head) appearance. This semi-slug is provisionally identified as a member of the genus Microparmarion. It may be Microparmarion austeni or a similar species (see Simroth, 1893). However, further research is required to confirm its identity.

The longfin bannerfish, Heniochus acuminatus, is known to occur in Singapore (see Fowler, 1938: 179; Tan & Lim, 2015), but the schooling bannerfish, Heniochus diphreutes, was not. Although herein presented as a probable Singapore record, it is highly unlikely for Heniochus diphreutes to be naturally present there. In the Southeast Asian region, it has only been confirmed to occur largely in oceanic coastal areas with cool upwelling, such as the Andaman Sea, and the Indian Ocean asts of Indonesia (Allen et al., 1998: 189- 190; Allen & Erdmann, 2012: 539). This, therefore, lends support to the cautionary remark by Tweedie (1940: 68) that specimens ‘... from the fishmarkets, while the majority probably come from the neighbourhood of Singapore, may have been caught five hundred miles and more away and should not, in (his) opinion, be included in any list of fishes from... the Malay Peninsula’. The schooling bannerfish is widely distributed across the Indo- acific from the Red Sea to Hawaii, apparently being more common in subtropical localities. It frequently forms large aggregations and is mainly found at depths of 5-210 m along oceanic coasts. Although it appears very similar to the longfin bannerfish, with which it is often sympatric, Heniochus diphreutes is distinguished by its shorter snout, more rounded breast and second black band ending at corner of anal fin [compared to the band ending behind corner of anal fin in Heniochus acuminatus] (Allen et al., 1998: 189-190; Allen & Erdmann, 2012: 538-539).