53. Insular Horseshoe Bat

Rhinolophus keyensis

French: Rhinolophe insulaire / German: Kei-lnseln-Hufeisennase / Spanish: Herradura insular

Other common names: Kai Horseshoe Bat

Taxonomy. Rhinolophus keyensis Peters, 1871, “ Key-Inseln [= Kai Islands], ” Indonesia.

Included in the megaphyllus species group. Previously considered a subspecies of R megaphyllus, but now recognized as a distinct species based on morphological and genetic data. R keyensis has been known by the name simplex, but keyensis is the oldest available name. Four subspecies recognized.

Subspecies and Distribution.

R k. keyensis Peters, 1871 - Moluccas Is (Bacan, Ambon), Gorong Archipelago, and Kai Is.

R k. amiri Kitchener, 1995 — E Lesser Sunda Is (Savu, Semau, and Roti).

R k. parvus R. E. Goodwin, 1979 - E Lesser Sunda Is (Timor).

R k. simplex K.Andersen, 1905 - Lesser Sunda Is ( Bali, Nusa Penida, Lombok, Sumbawa, Moyo, Sangeang, Komodo, Rinca, Flores, Lembata, Alor, Wetar, and Sumba).

Descriptive notes. Head-body 35-4—46- 6 mm, tail 17-26- 2 mm, ear 14—20 mm, hindfoot 5-9-8- 4 mm, forearm 35-8-44- 9 mm. The Insular Horseshoe Bat is a variable species of horseshoe bat, similar to the Eastern Horseshoe Bat ( megaphyllus), and differing by: being generally smaller in most measurements; having anterior basisphenoid with marked depression rather than shallow groove that runs smoothly into basioccipital surface; and having distinct baculum, with more bulbous base. In races simplex and keyensis, dorsal pelage is blackish brown (sometimes russet), whereas ventral pelage is lighter drab brown; in parvus, dorsum is more cinnamon brown and ventral pelage is fawn brown, apparendy with pale patch behind ear; race amiri is dark as in simplex (on Roti), or lighter as in parvus (on Semau), or blackish brown on rump grading to paler medium brown on neck, shoulders, and upper back with cream ventral pelage, becoming darker on abdomen (Savu). Ears are moderately long. Noseleaf has long lancet with a blunt tip and slighdy concave sides; sella is smoothly curved at dp and parallel-sided (sella smaller in keyensis), as well as variably constricted on sides; horseshoe is wide at 8- 2 mm, and has obvious median emarginadon; secondary leaflets present. Lower lip has three mental grooves. Baculum is moderately long (2-5- 3-5 mm in length) and dorsally straight with bulbous and weakly to strongly bifurcated base. Skull is of medium build (zygomatic width is slighdy larger than, or subequal to, mastoid width); anterior nasal swellings are moderately to well developed; supraorbital crests usually join behind midpoint of orbital cavity (occasionally join is anterior to this point). P2 is small with well-developed cusp and is usually within tooth row, separating C1 and P4 widely; P3 is either partially displaced from tooth row or fully displaced, sometimes allowing P2 and P4 to touch.

Habitat. Recorded in open woodlands at 500 m elevation on Savu Island.

Food and Feeding. No information.

Breeding. No information.

Activity patterns. No information.

Movements, Home range and Social organization. No information.

Status and Conservation. Classified as Data Deficient on The IUCN Red List. The Insular Horseshoe Bat is found over a number of islands; many of these islands have experienced drastic and large-scale habitat destruction, which may affect this species adversely. Virtually nothing is known regarding this species’ ecology and the threats it faces, and further research is needed.

Bibliography. Corbet & Hill (1992), Csorba & Bates (2016b), Csorba et al. (2003), Flannery (1995a), Kitchener, Schmitt et al. (1995), Koopman & Gordon (1992).