79.

Western Long-eared Bat

Nyctophilus major

French: Nyctophile de Perth / German: GroRe Langohrfledermaus / Spanish: Nictofila de Perth

Other common names: Greater Long-eared Bat

Taxonomy. Nyctophilus major J. E. Gray, 1844,

Perth, Western Australia, Australia.

As currently recognized, Nyctophilus includes seven species groups: major, goulds, microtis, bifax, microdon, geoffroyi, and howensis . Nyctophilus major is in the major species group along with N. corbeni and possibly N. daedalus . Nyctophilus and sister genus Pharotis have generally been included as a separate tribe in Vespertilioninae (Nyctophilini) or as a separate subfamily ( Nyctophilinae), but genetic data from Nyctophilus have recently placed it sister to Chalinolobus in Vespertilionini . Nyctophilus major was previously included under N. timoriensis as a subspecies; however, the name timoriensis is considered a species inquirenda because of ambiguity of type locality, lack of definitive type specimen, and lack of an adequate enough description or illustration to identify the name to any currently recognized species. What was previously recognized as N. timoriensis has been broken into four distinct species: N. major, N. corbeni, N. sherrini, and N. shirleyae . Specimens of Nyctophilus from TimorIsland recently obtained by K. M. Helgen apparently bare resemblance to N. heran, but comparison of these specimens to other Nyctophilus has not been done, and the name fimoriensis will continue to go unused for now. Two subspecies recognized.

Subspecies and Distribution.

N.m.major].E.Gray,1844—SWWesternAustralia.

N. m. tor Parnaby, 2009 — WC (one record) & S Western Australia and S South Australia E to Eyre Peninsula.

Descriptive notes. Head-body 51-65 mm, tail 40-52 mm, ear 21-5-28-6 mm, forearm 37-6-48-4 mm; weight 11-17-5 g. Males are a little smaller than females. The Western Long-eared Bat has very large ears and unique simple noseleaf consisting of two ridges, one further on muzzle and another immediately above nostrils, with vertical groove in middle and furred trough between them. Dorsal pelage is dark grayish brown; venter is lighter grayish white. Rostrum, ears, and wing membranes are dark blackish brown. Rostrum is short and blunt, with ridge across muzzle over nostrils that is low, broad, and without vertical groove. Ears are very large and broad, with bluntly rounded tips, horizontal ribbing on inner surfaces, inward curved anterior edges, and smooth posterior edges (ears can fold back at top ofthick part of anterior edge); large and furred interauricular band crosses forehead between ears; tragus is small and bluntly rounded at tip, being convex on anterior margin. Glans penis has comparatively large urethral lappets, and distal part is simple and lacks any protrusions. Baculum is 4-2—4-6 mm long, with moderately thin shaft (but thick in terms of Nyctophilus) that constricts right before tip in dorsal view; tip has very small notch in dorsal view, and base is strongly bifurcated; in lateral view, baculum is curved downward at base, but shaftis straight to narrowed tip. Skull is robust and narrower than in Corben’s Long-eared Bat (N. cor beni) but broader than in the Tasmanian Long-eared Bat (NV. sherrini); rostrum is short, broad, and robust; braincase is narrow, zygomatic arches are less rounded compared with Corben’s Long-eared Bat, and palate is longer; sagittal and lambdoidal crests are moderately developed; and M? and lower molars are extremely reduced. Dental formula for all species of Nyctophilusis11/3,C1/1,P1/2,M 3/3 (x2) =

Habitat. Generally Banksia (Proteaceae) woodlands, Casuarina (Casuarinaceae) and Melaleuca (Myrtaceae) forests, and tall eucalypt forests with high annual rainfall, preferring habitats with well-developed shrub understories.

Food and Feeding. Western Long-eared Bats primarily forage by perch-hunting, and they use passive listening with their large ears to locate prey; they probably use echolocation in some cases. Crickets are common prey, but a variety of other insects are eaten. They are known to glean insects off the ground and also have been observed foraging on the ground at times. They are slow fliers (6-9 km/h while foraging), but they have higher wing loading than other species of Nyctophilus, implying higher flight speed.

Breeding. Western Long-eared Bats breed once a year in March—May; captive individuals have copulated as late as June. Spermatogenesis begins in November, and peak testicular size is attained in March, declining until May when males have enlarged epididymides but not enlarged testes. Sperm storage in females occurs in cauda isthmus of the oviduct and endometrial glands near utero-tubal junction; ovulation and fertilization are delayed until late August or September. Twins are born from late October to November, and volant young are first noted in December. Lactating females can be captured until February when young are weaned.

Activity patterns. Western Long-eared Bats are nocturnal. They spend the day roosting in hollows and fissures of tree trunks and limbs and leave around dusk to forage. They often roost in mature or dead Eucalyptus rudis and Melaleuca rhaphiophylla (both Myrtaceae). They are able to enter torpor to conserve energy during harsh conditions and during the day as needed. Their body temperature is normally 35°C, but it can drop to within 1-5°C of ambient temperature. Torpor provides metabolic savings of ¢.95% under ambient temperatures of5-15°C. They reportedly enter torpor at ambient temperatures of5-23°C and can spontaneously arouse at any time. They can maintain torpor for ¢.60 days straight if they rely solely on fat reserves. Call shape is very steep FM sweep, with peak frequencies of 42-47 kHz (mean 44-4 kHz) that cannot be easily identified from other long-eared bats.

Movements, Home range and Social organization. Western Long-eared Bats roost alone or in pairs, and they switch roosts often, only staying at a roost for 1-2 days. They only move a short distance between each roost, and roosts are located relatively close to foraging areas, resulting in travel of ¢. 1200 m to feed.

Status and Conservation. Not assessed on The IUCN Red List. The Western Long-eared Bat has a wide distribution and does not seem to have any major threats.

Bibliography. Bailey & Haythornthwaite (1998), Bullen & McKenzie (2002a, 2002b), Churchill (2008), Hosken (1996, 1997a, 1997b), Hosken, Bailey et al. (1994), Hosken, Blackberry et al. (1998), McKenzie (2008), Parnaby (2009).