Rhinolophus alcyone, Temminck, 1852

Burgin, Connor, 2019, Rhinolophidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 280-332 : 281-282

3 . Halcyon Horseshoe Bat

Rhinolophus alcyone

French: Rhinolophe alcyone / German: Alcyon-Hufeisennase / Spanish: Herradura alción

Taxonomy. Rhinolophus aZcyon « Temminck, 1853 ,

“ La rivière Boutry à la Guiné [= Boutry River , Guinea] .”

Rhinolophus alcyone is in the landeri species group with R landeri , R guineensis , R blasii , and R lobatus . It is genetically close to R landeri , although additional sampling is needed to fully resolve its placement Although no subspecies are recognized, there are distinct pelage differences between eastern and western populations and the Bioko Island population, suggesting taxonomic revision is needed. Specimens from Gabon might represent R silvestris , which requires additional investigation. Monotypic.

Distribution. W & C Africa from Senegal to Togo and from S Nigeria, S Cameroon, and SW Central African Republic to W Republic of the Congo, Equatorial Guinea and Bioko I, and Gabon, also patchily in Congo Basin, SW South Sudan, and W Uganda.

Descriptive notes. Head—body c. 57—68 mm, tail 18—32 mm, ear 19—25 mm, hindfoot 11-13 mm, forearm 48-56 mm; weight 14—23 g. Typical dorsal pelage is dark to medium brown (hairs are yellowish beige with brown tips); ventral pelage is slighdy paler. Orange-morph pelage is pale brown to bright orange-red, which is rare. Intermediate form has been recorded where body was dark brown, with orange-brown rump. Some males have bright orange axillary tufts. Ears are comparatively short (36—49% of forearm length) and have 8—9 internal folds. Noseleaf has subtriangular lancet, with straight or slightly concave margins; tip is bluntly pointed; sella has extremely short white hairs and is narrow with straight, almost parallel sides; top of sella is rounded and curved forward; connecting process is well developed and subtriangular, with bluntly to sharply pointed tip; horseshoe is of medium breadth (8-3-11- 2 mm) and nearly covers muzzle; and there are lateral leaflets present and median emargination. Lower lip has well-defined median groove and two poorly defined lateral grooves. Wings are medium to blackish brown, and first phalanx of fourth finger is relatively short (19—22% of fourth metacarpal). Uropatagium is paler brown; one specimen had cream uropatagium, with dark brown reticulation. Skull is robust, and zygomatic arches are moderately robust; zygomatic width is greater than mastoid width; nasal swellings are relatively high; anterior medium swellings are globular and prominent; lateral and posterior swellings are not as prominent; frontal depression is very shallow; supraorbital ridge is weak; and sagittal crest is variably developed, being low to well developed. P2 is in tooth row or slightly displaced labially; C1 and P4 are well separated; P3 can be either displaced labially from tooth row or within it; and P2 and P4 are separated.

Habitat. Closed tropical moist forests and also savanna with pockets ofsuitable habitat.

Food and Feeding. The Halcyon Horseshoe Bat is insectivorous.

Breeding. One lactating and three pregnant Halcyon Horseshoe Bats were captured in western Uganda in midJune, and a birth was recorded in September. In Ivory Coast, four pregnant females were captured in mid-February.

Activity patterns. During the day, Halcyon Horseshoe Bats roost in caves, hollow trees, roofs of thatched houses, and old mine shafts. Call frequency is 87 kHz in Uganda.

Movements, Home range and Social organization. Halcyon Horseshoe Bats often occur in colonies of up to 20 individuals and occasionally alone. They have been recorded roosting with Cameroon Horseshoe Bats (7 t alticolus ).

Status and Conservation. Classified as Least Concern on The IUCN ed List. Although the Halcyon Horseshoe Bat is considered rare and difficult to find, it is widespread and is currently considered not threatened. Potential threats include habitat loss from logging and agricultural expansion. It is hunted for food in some areas, which might be a localized threat.

Bibliography. ACR (2018), Csorba et al. (2003), Grubb et al. (1998), Happold, M. (2013p), Monadjem, Taylor, Jacobs & Cotterill (2017a), Rosevear (1965).

Figures

On following pages: 4. Lander's Horseshoe Bat (Rhinolophus landeri); 5. Guinean Horseshoe Bat (Rhinolophus guineensis); 6. Blasius's Horseshoe Bat (Rhinolophus blasii); 7. Peters's Horseshoe Bat (Rhinolophus lobatus); 8. Swinny's Horseshoe Bat (Rhinolophus swinnyi); 9. Cape Horseshoe Bat (Rhinolophus capensis); 10. Gorongosa Horseshoe Bat (Rhinolophus gorongosae); 11. Roberts's Horseshoe Bat (Rhinolophus rhodesiae); 12. Bushveld Horseshoe Bat (Rhinolophus simulato/); 13. Dent's Horseshoe Bat (Rhinolophus denti); 14. Cameroon Horseshoe Bat (Rhinolophus alticolus); 15. Mehely's Horseshoe Bat (Rhinolophus mehelyi); 16. Mediterranean Horseshoe Bat (Rhinolophus euryale); 17. Hildebrandt's Horseshoe Bat (Rhinolophus hildebrandtii); 18. Mount Mabu Horseshoe Bat (Rhinolophus mabuensis); 19. Cohen's Horseshoe Bat (Rhinolophus cohenae); 20. Smithers's Horseshoe Bat (Rhinolophus smithersi); 21. Mozambican Horseshoe Bat (Rhinolophus mossambicus); 22. Rüppell's Horseshoe Bat (Rhinolophus fumigatus); 23. Eloquent Horseshoe Bat (Rhinolophus Bloquons).

Distribution. W & C Africa from Senegal to Togo and from S Nigeria , S Cameroon , and SW Central African Republic to W Republic of the Congo , Equatorial Guinea and Bioko I, and Gabon , also patchily in Congo Basin, SW South Sudan , and W Uganda .