Emballonura dianae, Hill in Wolff, 1956

Bonaccorso, Frank, 2019, Emballonuridae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 350-373 : 360-361

24 . Large-eared Sheath-tailed Bat

Emballonura dianae

French: Emballonure de Diana / German: Diana-reischwanzfledermaus / Spanish: Embalonuro de Diana

Taxonomy. Emballonura dianae Hill in Wolff, 1956 ,

Te-Abagua Cave, near Tigoa, Rennell Island , Solomon Islands.

Three subspecies are recognized.

Subspecies and Distribution.

E. d. dianae Hill, 1956 - Solomon Is (Malaita, Guadalcanal, and Rennell).

E. d. fruhstorferi Flannery, 1994 — Papua New Guinea (Western, Southern Highlands, and Gulf provinces).

E. d. rickwooodi Flannery, 1994 - Bismarck Archipelago (Mussau, New Britain, and New Ireland Is), and N & W Solomon Is (Bougainville and Santa Isabel Is).

Descriptive notes. Head-body 48-64 mm, tail 11-16 mm, ear 14-5-17-9 mm, hindfoot 7 9-9-1 mm, forearm 42-48 mm; weight 5-10-5 g. As reflected by its common name, the Large-eared Sheath-tailed Bat has broad, funnel-like ears. Tragus is notched at its base and has small pointed projection at front upper margin. Lips are thick, and upper lip overhangs lower. Dorsal fur is bicolored, with red-brown to medium brown tips over whitish bases. Subspecies rickwoodi has tricolored ventral hair that is whitish at bases and tips and reddish brown in between; however, specimens from New Ireland have white throat and posterior margin of body. Subspecies fruhstorferi shows little difference between brown dorsal and ventral fur.

Habitat. Rainforests and mossy (cloud) forests from sea level to elevations of at least 1400 m. On Mussau Island, Large-eared Sheath-tailed Bats were observed foraging along beaches and in forest clearings and groves of coconut palms.

Food and Feeding. The Large-eared Sheath-tailed Bat is insectivorous. Five individuals were captured in a short time in mist nets on New Britain Island when they were attracted to lights that primarily attracted moths, suggesting group foraging might occur.

Breeding. Female Large-eared Sheath-tailed Bats carrying one embryo each have been collected in September, a lactating female was reported from June, and volant juveniles were reported in December. These scant data suggest the possibility that polyestry occurs with two birth peaks each year.

Activity patterns. The Large-eared Sheath-tailed Bat is crepuscular and roosts in dimly lit limestone cave entrances. Echolocation search call is a multiharmonic QFM call, with greatest energy of c.35 kHz in second harmonic. Call begins with upsweep tick and terminates in very slight downward tick.

Movements, Home range and Social organization. Large-eared Sheath-tailed Bats will cohabit twilight zones of caves with multiple other species of bats including the New Guinea Sheath-tailed Bat { Emballonura furax ), Raffray’s Sheath-tailed Bat { E. raffrayand ), and Beccari’s Sheath-tailed Bat { E. beccarii ). Small groups individually space themselves a few centimeters apart on vertical rock walls in day roosts.

Status and Conservation. Classified as Least Concern on The IUCNRed List. The Largeeared Sheath-tailed Bat has a large distribution and presumably large and stable overall population. Its widely scattered known localities where presence is confirmed are almost certainly due to lack of research rather than highly fragmented populations. Suitable conservation actions would be protection of known roosting caves and identification of additional important roosting caves. The Large-eared Sheath-tailed Bat is not known to occur in protected areas, but it might occur in some in Papua New Guinea. Timber harvest in many parts of its distribution is a growing threat that should be examined because it has been a decade since its previous review on The IUCNRed List.

Bibliography. Bonaccorso (1998), Bonaccorso, Leary & Hamilton (2008 a), Flannery (1994, 1995a, 1995b), Hill (1956), Whitmore (2015).

Figures

On following pages: 22. New Guinea Sheath-tailed Bat (Emballonura furati); 23. Beccari's Sheath-tailed Bat (Emballonura beccarti); 24. Large-eared Sheath-tailed Bat (Emballonura dianae); 25. Seri'sSheath-tailed Bat (Emballonura sertii); 26. Pacific Sheath-tailed Bat (Emballonura semicaudata); 27. Western Sheath-tailed Bat (Paremballonura tiavato); 28. Peters's Sheath-tailed Bat (Paremballonura atrata); 29. African Sheath-tailed Bat (Coleura afra); 30. Seychelles Sheath-tailed Bat (Coleura seychellensis); 31. Madagascar Sheath-tailed Bat (Coleura kibomalandy); 32. Dark Sheath-tailed Bat (Mosia nigrescens); 33. Chestnut Sac-winged Bat (Cormura brevirostris); 34. Gray Sac-winged Bat (Balantiopteryx plicata); 35. Thomas's Sac-winged Bat (Balantiopteryx io); 36. Ecuadorian Sac-winged Bat (Balantiopteryx infusca).

Subspecies and Distribution. E. d. dianae Hill, 1956 - Solomon Is (Malaita, Guadalcanal, and Rennell). E. d. fruhstorferi Flannery, 1994 — Papua New Guinea (Western, Southern Highlands, and Gulf provinces). E. d. rickwooodi Flannery, 1994 - Bismarck Archipelago (Mussau, New Britain, and New Ireland Is), and N & W Solomon Is (Bougainville and Santa Isabel Is).