148.

Common Butterfly Bat

Glauconycteris argentata

French: Glauconyctére argenté / German: Gewohnliche Schmetterlingsfledermaus / Spanish: Glauconicterio argentado

Other common names: Silvered Butterfly Bat, Silvery Butterfly Bat, Silvered Bat

Taxonomy. Chalinolobus argentatus Dobson, 1875,

“ Cameroon Mountains, western equatorial Africa,” Cameroon.

Analysis of mitochondrial genes retrieved G. argentata as sister to a clade including G. egeria, G. poensis, and G. alboguttata . Monotypic.

Distribution. Widespread in C & E Africa, from Cameroon and Equatorial Guinea (Mbini) into DR Congo, Rwanda, Burundi, Uganda, Kenya, Tanzania, NW Angola, and N Malawi.

Descriptive notes. Head-body ¢.53-61 mm, tail 41-53 mm, ear 8-14 mm, hindfoot 5-10 mm, forearm 39-44 mm; weight 6-12 g. Pelage is dense, with ¢. 7 mm mid-dorsal hairs. Pelage color varies geographically. In savanna habitats, dorsal pelage is pale golden fawn, pale cinnamon, or pale grayish brown, being paler on head. In rainforest habitats, dorsal pelage is darker and grayer, sometimes with silvery sheen. Paler dorsal flank-stripe is present but indistinct in some individuals. Dorsal pelage extends overfirst one-quarter of uropatagium. Ventral pelage is darker and grayer than dorsal pelage. Ears are rounded and brown, with inner margin moderately long and rounded and backward-pointing lobe at base, and outer margin with rectangular antitragus and connected with smooth, broad, rounded, fleshy lobe on lower lip near corner of mouth. Eyes are very small. Wings and uropatagium are translucent, pale brown, and faintly reticulated near body. Tibia is long (17-20 mm) for Glauconycteris . Head is high-domed, and muzzle is short, broad, and flattish. Skull is small, and profile of forehead is weakly concave compared with other Glauconycteris . I* is very long, slender, unicuspid, and weakly or strongly bicuspid. Lowerincisors are tricuspid or with four cusps and not crowded.

Habitat. Lowland tropical moist forests, bamboo forests, and moist savanna habitats, often recorded over streams, rivers, pools, and fish ponds.

Food and Feeding. No information.

Breeding. About ten adult Common Butterfly Bats with young were observed in December at Uzungwa Scarp Forest Reserve, central Tanzania. Four of eight females captured in Kenya in March carried young, and two lactating females were recorded in June.

Activity patterns. At Uzungwa Scarp Forest Reserve, ten females and their young roosted underneath leaves of palm trees. Echolocations from Gabon have minimum frequencies of 28-4-34-5 kHz, maximum frequencies of 78-101-6 kHz, peak frequencies of 40-3-47-1 kHz, durations of 2-3 milliseconds, maximum energies of first harmonic of 81:8-104-6 kHz, and interpulse intervals of 24-128 milliseconds. In Kenya, minimum frequencies were 16-3—40-6 kHz, maximum frequencies were 41.4-75-1 kHz, peak frequencies were 36-2—44-8 kHz, and durations were 0-7-8-5 milliseconds.

Movements, Home range and Social organization. Small groups of up to 30 Common Butterfly Bats roosting in palms and other trees have been reported. Individuals cling to leaves near midribs in groups of 2—4 individuals on each leaf.

Status and Conservation. Classified as Least Concern on The IUCN Red Lust.

Bibliography. Happold, M. (2013au), Hassanin et al. (2018), Lépez-Baucells, Rocha et al. (2017), Peereboom et al. (2012).