Micronomus norfolkensis
Creators: name: Wilson, Don E.
name: Mittermeier, Russell A.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Chiroptera
Molossidae
Micronomus
Micronomus norfolkensis

description: 117. East Coast Free-tailed Bat <i>Micronomus norfolkensis</i> <b>French:</b> Tadaride de Norfolk / <b>German:</b> Ostkisten-Bulldogfledermaus / Spanish: Murciélago rabudo de Norfolk <b>Other common names:</b> East Coast Mastiff Bat, Eastern Freetail Bat, Eastern Little Mastiff Bat, Norfolk Island Mastiff Bat <b>Taxonomy.</b> Molossus norfolkensis J. E. Gray, 1839, type locality not given. Restricted by T. B. Reardon and colleagues in 2008 to “possibly Norfolk Island, Australia.” There has been much confusion about the type locality of Norfolk Island as there 1s no evidence the species occurs or has ever occurred there; it is likely the specimen originated from mainland Australia. For most of the past century, this species has generally been placed in the genus Mormopterus, but revisions by T. B. Reardon and colleagues in 2008 and 2014 have established that it is morphologically and genetically distinct from Mormopterus and other Australian molossid lineages (Ozimops and Setirostris). Based on this, in 2014 Reardon and colleagues reinstated it as sole member of Micronomus, a subgenus of Mormopterus, Micronomus was then re-elevated to genus level by S. M. Jackson and C. P. Groves in 2015. The genus Micronomus was first proposed by T. Iredale and E. Le G. Troughton in 1934 but as a nomen nudum (dubious name); it was subsequently validated by Troughton in 1944. Monotypic. <b>Distribution.</b> E side of Great Dividing Range along E coast ofAustralia, extending from Conondale Range in SE Queensland S to Bega on South Coast, SE New South Wales. <b>Descriptive notes.</b> Head-body 50-55 mm, tail 32-45 mm, ear 13-16 mm, forearm 35-41 mm; weight 6-12 g. The East Coast Free-tailed Bat can be distinguished from most other Australian free-tailed bats by its relatively small size, narrow tapered muzzle, and fleshy projections on genitalia of both males and females; these characteristics are shared with the Hairy-nosed Free-tailed Bat (Setirostris eleryi) but the East Coast Free-tailed Bat is slightly larger and lacks bristles on muzzle; the two species do not overlap in range, being separated by the Great Dividing Range. Skull is domed rather than flat. M' and M? are very distinctive, without typical hypocone, and with scallop-shaped lobes extending from posterolingual margin of heel, with most anterior lobe in position typical of a hypocone. Dental formulais11/2, C1/1, P 2/2, M 3/3(x2) =30. This species exhibits fixed allelic differences from other Australian free-tailed bats at a minimum of 17 independent allozyme loci, and highly divergent mtDNA haplotypes, with divergence greater than 14%. <b>Habitat.</b> Associated with a range of habitats including eucalypt forests and woodlands, mangroves, wet sclerophyll forests, and rainforest. <b>Food and Feeding.</b> Diet consists mostly of moths and midges, but East Coast Free-tailed Bats less frequently consume a large range of invertebrates including cockroaches, beetles, flies, true bugs, wasps, and ants. They show a preference to forage in open riparian areas associated with low-lying coastal floodplains, and wetlands. <b>Breeding.</b> Females give birth from late November to early December. <b>Activity patterns.</b> The East Coast Free-tailed Bat is nocturnal, emerging ¢.35 minutes after sunset to forage above canopy height or in open areas or forest gaps with little vegetation. It roosts in tree hollows, often in dead branches and “spouts” with very small entrances (c. 20 mm diameter) in mangroves, large trees, paddock trees in farmland, and remnant vegetation in urban areas. It is also known to roost under metal caps on wooden power poles, in buildings and manufactured bat roostboxes. <b>Movements, Home range and Social organization.</b> East Coast Free-tailed Bats generally roost individually or in small groups of up to eight individuals. Roosts are switched almost nightly (average of 1-3 nights/roost) and several roosts are often close to each other within a patch of less than 200 m, suggesting territorial roosting fidelity. They sometimes share roosts with other species, including the Eastern Broad-nosed Bat (Scotorepens orion) and Gould’s Wattled Bat (Chalinolobus gouldii). Despite the proportionately long wingspan suggestive of fast, sustained flight, radio-tracked bats have generally flown relatively short distances between roost trees and foraging areas each night, up to a maximum of 6 km but more typically c. 2-3 km. Lactating females have overlapping home ranges of 3500-4500 ha. <b>Status and Conservation.</b> Classified as Vulnerable on The IUCN Red List (as Mormopterus norfolkensis) because the number of mature individuals is estimated to be less than 10,000, and habitat loss is causing continuing declines of greater than 10% of the population over three generations. The distribution of the East Coast Free-tailed Bat coincides with the areas of densest human population in Australia, including the Sydney basin; the flat, fertile parts of the landscape favored by the bats are also preferred by humans for agriculture and housing. The species is likely to face ongoing habitat loss due to expanding urban development along the east coast between Brisbane and Sydney. <b>Bibliography.</b> Adams etal. (1988), Hoye, Law &amp; Allison (2008), Iredale &amp; Troughton (1934), Jackson &amp; Groves (2015), McConville (2013), McConville &amp; Law (2013), McConville et al. (2013), Reardon, Adams et al. (2008), Reardon, McKenzie et al. (2014), Troughton (1944), Woinarski et al. (2014).
description: Published as part of <i>Don E. Wilson &amp; Russell A. Mittermeier, 2019, Molossidae, pp. 598-672 in Handbook of the Mammals of the World – Volume 9 Bats, Barcelona :Lynx Edicions</i> on pages 668-669, DOI: 10.5281/zenodo.6418279