Artibeus watsoni, Thomas, 1901

Don E. Wilson & Russell A. Mittermeier, 2019, Phyllostomidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 444-583 : 576-577

200.

Thomas's Fruit-eating Bat

Artibeus watsoni

French: Dermanure de Watson / German: Thomas-Fruchtvampir / Spanish: Artibeo de Watson

Other common names: Watson's Fruit-eating Bat

Taxonomy. Artibeus watson: Thomas, 1901 ,

“Bogava [= Bugaba,] Chiriqui, Panama. Altitude 250 m.”

Artibeus watsoni is placed in Dermanura by some authors, but it was reassigned to Artibeus (subgenus Dermanura ) after reinterpretation of molecular results. Dermanura jucundum Elliot 1906 from Veracruz (S Mexico) has been considered a synonym; A. incomitatus described by E. K. V. Kalko and C. O. Handley, Jr., 1994 from Isla Escudo ( Panama) is molecularly the same as A. watson . Other authors also listed A. rosenbergi from north-western Ecuador as a synonym, but it is a distinct species based on molecular and morphological analyses. Monotypic.

Distribution. From S Mexico (Veracruz) through Central America (mainly in the Caribbean lowlands of Costa Rica) to SE Panama. Records from NW South America would represent A. rosenbergi , which was thought to be part of this taxon.

Descriptive notes. Head-body 50-58 mm (tailless), ear 14-17 mm, hindfoot 8-12 mm, forearm 35-41 mm; weight 9-15-6 g. Thomas’s Fruit-eating Bat is small, with facial stripes and short broad rostrum. Dorsalfur is gray-brown or tan, long (6-7 mm), fluffy, and faintly tricolored. Rostrum has two well-marked white facial stripes, but supraocular is more evident than subocular. Ventralfur is slightly paler than dorsum. Ears and noseleaf are pale brown, and bases of ears are sometimes edged in white, cream, or rarely yellow. Horseshow of noseleafis free. Fur covers more than one-half of each forearm. Wing membranes are brownish, except for second interdigital membrane that lacks pigmentation. Tail membrane is pale brown, moderated in size (10-12 mm), U-shaped, and almost completely naked. Dental formulais12/2,C1/1,P2/2,M 2/3 (x2) = 30. Skull has inflated frontal and supraorbital areas. Hypocone (talon) on M' is narrow, and M, is small, but it does not have defined cusps.

Habitat. Common to abundant in semideciduous and evergreen lowlands forests, second growth, and fruit groves and also upland and swamp forests on islands from lowlands to elevations of ¢. 1500 m (usually below 800 m). Thomas’s Fruit-eating Bat favors taller and more humid forests than the Pygmy Fruit-eating Bat (A. phaeotis ).

Food and Feeding. Thomas’s Fruit-eating Bat is mainly frugivorous and includes fruits of Ficus spp. ( Moraceae ), Cecropia spp. ( Urticaceae ), and Piper spp. ( Piperaceae ) in its diet.

Breeding. Breeding pattern of Thomas's Fruit-eating Bat has been characterized as a bimodal polyestry. Most reproductive females were found in February and June but records include February-April,July-August, and November. Without exception, each gravid female had one embryo.

Activity patterns. Thomas’s Fruit-eating Bats is nocturnal. It seems to be active at the first hour after sunset and again in early morning hours. It appears to be an obligate tent-maker because it has not been found roosting in other situations. For tents,it modifies leaves of Heliconia (Heliconiaceae) , banana ( Musaceae ), bifid and palmate palm ( Anthurium , Araceae ), and species of Cyclanthaceae . Leaves are cut in a variety of styles, depending on shape and size. Individuals (usually males) occupying a tent roost make distinctive multiharmonic social call. These calls could help females find available roosts, or indicate presence of a male in the tent to other males.

Movements, Home range and Social organization. Thomas’s Fruit-eating Bat roost alone or form small groups. Variation in roost fidelity among males and females, and among individuals under different breeding conditions, depended on relative roost availability. In a fragmented landscape in Panama, home ranges of radio-tracked individuals varied widely from 1-8 ha to 17-9 ha (mean c.9 ha).

Status and Conservation. Classified as Least Concern on The IUCN Red List (as Dermanura watsoni ). Thomas's Fruit-eating Bat has a wide distribution, is locally common, occurs in protected areas, and is tolerant of some degree of habitat modification, suggesting population stability.

Bibliography. Albrecht et al. (2007), Andersen (1908c), Chaverri et al. (2007), Davis (1970a), Gillam et al. (2013), Kalko & Handley (1994), LaVal & Rodriguez-Herrera (2002), Reid (2009), Rodriguez-Herrera et al. (2007), Stoner (2001), Thomas (1897a, 1901a), Timm (1987).

Figures

187. Brown Fruit-eating Bat (Artibeus concolor), 188. Honduran Fruit-eating Bat (Artibeus inopinatus), 189. Fraternal Fruit-eating Bat (Artibeus fraterculus), 190. Hairy Fruit-eating Bat (Artibeus hirsutus), 192. Ecuadorian Fruit-eating Bat (Artibeus aequatorialis), 193. Jamaican Fruit-eating Bat (Artibeus jamaicenss), 194. Dark Fruit-eating Bat (Artibeus obscurus), 195. Schwartz’s Fruit-eating Bat (Artibeus schwartzi), 196. Great Fruit-eating Bat (Artibeus lLituratus), 197. Large Fruit-eating Bat (Artibeus amplus), 198. Flat-faced Fruit-eating Bat (Artibeus planirostris), 199. Rosenberg’s Fruit-eating Bat (Artibeus rosenberg), 200. Thomas's Fruit-eating Bat (Artibeus watsoni), 201. Toltec Fruit-eating Bat (Artibeus toltecus), 202. Pygmy Fruit-eating Bat (Artibeus phaeotis), 203. Gervais’s Fruit-eating Bat (Artibeus cinereus), 204. Andersen’s Fruit-eating Bat (Artibeus anderseni), 205. Little Fruit-eating Bat (Artibeus ravus), 206. Aztec Fruit-eating Bat (Artibeus aztecus), 207. Bogota Fruit-eating Bat (Artibeus bogotensis), 208. Silvery Fruit-eating Bat (Artibeus glaucus), 209. Dwarf Fruit-eating Bat (Artibeus gnomus), 210. Jamaican Fig-eating Bat (Ariteus flavescens), 211. Tree Bat (Ardops nichollsi), 212. Red Fruit Bat (Stenoderma rufum), 213. Wrinkle-faced Bat (Centurio senex), 214. Ipanema Broad-nosed Bat (Pygoderma bilabiatum), 215. Visored Bat (Sphaeronycteris toxophyllum), 216. Little White-shouldered Bat (Ametrida centurio), 217. Cuban Fig-eating Bat (Phyllops falcatus)

Distribution. From S Mexico (Veracruz) through Central America (mainly in the Caribbean lowlands of Costa Rica ) to SE Panama . Records from NW South America would represent A. rosenbergi , which was thought to be part of this taxon.