Pteronotus psilotis, Dobson, 1878

Don E. Wilson & Russell A. Mittermeier, 2019, Mormoopidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 424-443 : 440

9.

Dobson’s Lesser Mustached Bat

Pteronotus psilotis

French: Ptéronote a oreilles nues / German: Kleine Dobson-Schnurrbartfledermaus / Spanish: Pteronotus de Dobson

Other common names: Dobson's Mustached Bat

Taxonomy. Chilonycteris psilotis Dobson, 1878 ,

type locality unknown. Restricted by IL. de Ia Towe in 1955 to “Tehuantepec, Oaxaca, Mexico.”

P. psilotis was formerly classified as a subspecies of P. personatus , but here it is considered a distinct species. Monotypic.

Distribution. From Sonora and Tamaulipas along Pacific and Gulf coasts of N Mexico, respectively, S to El Salvador and W Honduras.

Descriptive notes. Head-body c.45-54 mm, tail 15-18 mm, ear 16-18 mm, hindfoot 9-4-12 mm, forearm 40-8-45 mm; weight 6:5-7-4 g. Dobson’s Lesser Mustached Bat is the smallest species of mormoopid on the mainland. Pelage is highly variable in color. Dorsal fur is gray to brownish when hairs are new, becoming reddish brown and ocherous as hairs age. Ventral fur is bicolored; hairs of new pelage have brown bases and grayish or cinnamon tips; as hairs age, tips get reddish or almost yellowish. Dobson’s Lesser Mustached Bat resembles Wagner's Lesser Mustached Bat (PF. personatus ) externally and cranially but it has an average smaller overall size. Skull of Dobson’s Lesser Mustached Batis similar in size to that of Thomas’s Naked-backed Bat (PF. fulvus), which occurs in the same geographical area, but it is flatter in profile; rostrum 1s also narrower; and basioccipital region is less developed. Condylo-basal lengths are 13-2-14-5 mm.

Habitat. Woodlands of tropical deciduous and semideciduous forest, rainforest, and vegetation with well-developed canopies. Dobson’s Lesser Mustached Bat is usually associated with streams and rivers. Similar to Thomas’s Naked-backed Bat, Dobson's Lesser Mustached Bat has a narrow thermal tolerance for roosting;it prefers roosting in hot and humid caves or mines, which probably restricts habitats that it can use.

Food and Feeding. Dobson's Lesser Mustached Bat is known to eat insects, but there is no specific information available on prey items in its diet.

Breeding. Dobson's Lesser Mustached Bat is seasonally monoestrous, with females usually giving birth at beginning of rainy season. Males seem to form bachelor colonies during at least part of the year, with maternity colonies almost exclusively comprised of females. In Mexico, pregnant females have been reported in April-July, lactating females in July-September, and most records of young in August-December.

Activity patterns. Dobson’s Lesser Mustached Bat is reportedly crepuscular. On average, it uses the first four hours of the night to emerge and forage, returning immediately to its roost. Echolocation calls during search phase consist of short CF-FM pulses of 4-7 milliseconds. Second harmonic, which is most intense, is composed by initial short CF component at ¢.83 kHz, followed by downward FM sweep, and terminal short CF component of 65-68 kHz. Dobson’s Lesser Mustached Bats seem able to perform DSC.

Movements, Home range and Social organization. In Mexico, Dobson’s Lesser Mustached Bats are found in colonies that can exceed 10,000 individuals and in association with other mormoopids, particularly Thomas’s Naked-backed Bat, phyllostomids, and natalids. Colonies exhibit seasonal changes in size, with larger numbers of individuals most commonly reported during dry seasons. Fluctuations in colony size are probably related to seasonal movements for reproduction. Individuals were reported to maintain specific flyways in arroyos and canyon bottoms, foraging in areas 3-5 km from roosts.

Status and Conservation. Not assessed on The IUCN Red List. Dobson’s Lesser Mustached Bat is included under Wagner's Lesser Mustached Bat, which is classified as Least Concern.

Bibliography. Avila & Medellin (2004), Bateman & Vaughan (1974), GBIF Secretariat (2017), MacSwiney etal. (2006), O'Farrell & Miller (1997), Pavan & Marroig (2016), Smith (1972), Smotherman & Guillén-Servent (2008), de la Torre, J.A. & Medellin (2010), de la Torre, L. (1955), Torres-Flores et al. (2012).

Figures

1. Antllean Ghost-faced Bat (Mormoops blainuviller), 2. Peters’s Ghostfaced Bat (Mormoops megalophylla), 3. Davy’s Naked-backed Bat (Pteronotus davyi), 4. Thomas's Naked-backed Bat (Pteronotus fulvus), 5. Big Naked-backed Bat (Pteronotus gymnonotus), 6. Macleay’s Mustached Bat (Pleronotus macleayii), 7. Sooty Mustached Bat (Pleronotus quadridens), 8. Wagner's Lesser Mustached Bat (Pteronotus personatus), 9. Dobson’s Lesser Mustached Bat (Pteronotus psilotis), 10. Parnell’s Common Mustached Bat (Pteronotus parnellii), 11. Hispaniolan Common Mustached Bat (Preronotus pusillus), 12. Puerto Rican Common Mustached Bat (Pteronotus portoricensis), 13. Mexican Common Mustached Bat (Pteronotus mexicanus), 14. Mesoamerican Common Mustached Bat (Pteronotus mesoamericanus), 15. Allen’s Common Mustached Bat (Pleronotus fuscus), 16. Paraguana Common Mustached Bat (Pteronotus paraguanensis), 17. Womurs Common Mustached Bat (Pteronotus rubiginosus), 18. Amazonian Common Mustached Bat (Pteronotus alitonus)

Distribution. From Sonora and Tamaulipas along Pacific and Gulf coasts of N Mexico , respectively, S to El Salvador and W Honduras .