Vespertilionidae Gray, 1821

Wiantoro, Sigit, Flannery, Tim F., Brown, Dan, Armstrong, Kyle N. & Helgen, Kristofer M., 2023, The mammal fauna of Kofiau Island, off western New Guinea, Records of the Australian Museum 75 (5), pp. 653-662 : 659

Vespertilionidae Gray, 1821

Myotis sp. cf. stalkeri Thomas, 1910 . This distinctive fishing bat has been recorded from the Moluccan islands of Gebe and Kai Kecil, as well as from Waigeo and Batanta in the Raja Ampat group ( Meinig, 2002; Bouillard, 2021). Our tentative identification from Kofiau involves observation of a large insectivorous bat seen hawking within centimetres of the ocean surface off the south coast. The bat had narrow wings and appeared to be silvery in colour in torchlight. Although no calls were recorded from the bat detector while it was under observation, at least one, and possibly two, distinct echolocation call types, attributable to different species of Myotis were recorded at other times (call types 20 bFM and 30 bFM) ( Fig. 3 ). Given that Myotis can vary their calls depending on their activity, it is possible that both calls derive from one species.

Figures

Figure 3. Representative echolocation call sequence portions of the species identified (time between pulses has been compressed).20 bFM and 30 bFM: Myotis sp. cf. stalkeri; 53 st.cFM.d: Miniopterus sp. cf. australis; 16 fFM: Chaerephon jobensis; 35 i.fFM.d: Emballonura alecto; 63 i.fFM.d: Mosia nigrescens; 55 mCF: Hipposideros diadema; 55 lCF: Rhinolophus euryotis; 118 sCF: Aselliscus tricuspidatus.