Nyctophilus holtorum, Parnaby & King & Eldridge, 2021

Parnaby, Harry E., King, Andrew G. & Eldridge, Mark D. B., 2021, A New Bat Species from Southwestern Western Australia, Previously Assigned to Gould’s Long-eared Bat Nyctophilus gouldi Tomes, 1858, Records of the Australian Museum (Rec. Aust. Mus.) 73 (1), pp. 53-66 : 60-62

Nyctophilus holtorum sp. nov.

urn:lsid:zoobank.org:act:39AD0974-589C-4E9C-B075-E1D9A499AA7E

Figs 1–6

Holotype: WAM M.64188 (previously registered AM M.39799), field number 7HP43, adult male, body in alcohol, skull extracted, captured in a harp trap (bat trap) set on a forest road on the evening of 27 November, 2007 by H. Parnaby and T. Reardon. Field measurements (mm) of the holotype are: FA, 40.9; snout-vent length, 50; vent-tail tip length, 46; ear length (from notch), 26.2; hindleg length (with knee and ankle bent), 19.9; body weight, 9 g. Frozen tissue samples (liver) stored at the AM.

Paratypes: (total 8 adults, all bodies in alcohol). Northcliffe-

Windy Harbour Road , 200 m north of road to Mt Chudalup, D’Entrecasteau National Park, 34°45'37"S 116°05'06"E, WA, collected by H. Parnaby, T. Reardon and S. Ingleby on 27 November 2007: AM M.39806 (7HP29) and AM M.39807 (7HP30) both male. Northcliffe-Windy Harbour Road , 3.2 km south of road to Mt Chudalup, 34°47'17"S 116°04'30"E D’Entrecasteau National Park, WA, collected by H. Parnaby and T. Reardon on 27 November 2007: AM M.39809 (7HP33) female, AM M.39810 (7HP34) male; AM M.39811 (7HP38) male; AM M.39812 (7HP40) male; c. 10 km northeast of Waroona , 32°47'54"S 116°00'53"E, WA, collected H. Parnaby and T. Reardon on 27 November 2007: AM M.39813 (7HP41) female. Manjimup Post Office , 34°15'00"S 116°32'00"E: WAM M.19164, female, body in alcohol, skull extracted, collected by M. Sawle 1980. Frozen tissue samples (liver) stored at the AM and SAM for all paratypes except WAM M.19164.

Specimens examined. See Appendix. The type series consists of 9 specimens, others are referred specimens.

Type locality: State Forest c. 10 km northeast of Waroona , 32°47'54"S 116°00'53"E [WGS84 ± 20 m], Western Australia .

Diagnosis: A species of medium body size for the genus, closely resembling N. gouldi sensu stricto in external appearance, cranial and dental morphology but differs by an average sequence divergence of 5.0 % at the mitochondrial gene COI. It differs further in that the braincase tends to be broader for N. gouldi sensu stricto of equivalent GSL ( Figs 3 and 4 ), as reflected by greater MASB ( Fig. 3a ); the anterior of the braincase tends to be more inflated laterally, and the skull tends to be relatively shorter e.g., FA vs. GSL ( Fig. 3c ) and FA vs. CM3 ( Fig. 3d ).

Differs from N. daedalus sensu stricto, which has a relatively broader, larger skull (GSL: males greater than 17.3 mm, females greater than 17.6 mm); relatively much smaller auditory bullae that are set further apart, and more reduced M 3, i.e. the second and third “commissures” of M 3 are much shorter relative to the first commissure. Further differs in typically having a more developed (higher) post-nasal mound and relatively longer ears than N. daedalus sensu stricto.

Differs from sympatric N. geoffroyi in shape and relative development of the post-narial snout elevation, which is divided by a vertical median groove ( Fig. 5 ) compared to the distinct median Y-shaped groove in N. geoffroyi and the latter species averages smaller in general size, e.g., FA typically less than 38 mm; smaller mean body weight (e.g., combined sexes mean 6.3 vs. 10.0, Fullard et al., 1991).

Distinguished from sympatric N. major which has a low post-nasal snout mound and is a distinctly larger species, e.g., FA typically greater than 42 mm; GSL greater than 18.8 mm vs. less than 17.3; C1-C1 greater than 5.7 mm vs. less than 4.9 mm; CM3 greater than 7.0 mm vs. less than 6.2 mm.

Differs from N. major tor which has a low post-nasal snout mound; has a more reduced M 3; has a longer and more elongate baculum shaft, and averages larger for body and skull dimensions (see Parnaby, 2009).

Differs from N. arnhemensis Johnson, 1959 which has relatively shorter ears (less than 24 mm), a relatively smaller postnasal snout mound. If further differs from that species in relatively much larger auditory bullae, distal tip of the baculum forms a simple point compared to a bifid tip in N. arnhemensis , and the latter species has relatively much smaller urethral lappets.

Etymology. Named in honour of the late Dr John Holt and Mrs Mary Holt in recognition of their generous long-term support of Australian biodiversity research and conservation.

Distribution. Restricted to four IBRA regions in far southwestern Western Australia ( Fig. 6 ). We are aware of only one voucher-based locality record from the southern Avon Wheatbelt (from the Tambellup district), a region that has been extensively cleared of native vegetation. The specimen (WAM M.593) was collected by F. R. Bradshaw and registered in 1923 (probably Frederick Robert Bradshaw of Tambellup, Whittell, 1954). The species is primarily found in taller marri and jarrah forests with a dense shrubby understory. Two other Nyctophilus species are sympatric with N. holtorum sp. nov., N. major and N. geoffroyi .

Common name. Holt’s Long-eared Bat.

Figures

Figure 1. Highest maximum likelihood tree ofrelationships amongst Nyctophilus using:(a) 28 COI haplotypes, and (b) 21 CytB haplotypes. Bootstrap support (%) is shown at branch nodes.All M numbers refer to AM specimens except where indicated.

Figure 2. Specimen scores on the first two axes of a PCA based on a correlation matrix of nine cranial characters of adult male N. holtorum sp. nov. (squares, n = 6) and N. gouldi sensu stricto (circles, n = 79): (a) PCA scores grouped by species, and (b) same plot with N. gouldi coded by four geographic localities: montane and subcoastal NSW and far southeastern Qld (closed circles); southern and eastern Victorian montane regions (closed diamonds); inland and northern Qld (open circles) and inland NSW and northern Victoria (triangles).

Figure 3. Bivariate plots (mm) showing overlap in measurements of adult N. holtorum sp. nov. (squares, polygons) and adult N. gouldi sensu stricto (circles). Solid symbols are females, open symbols male: (a), condylo-basal skull length (CON) vs. least inter-temporal breadth (INT); (b) CON vs. mastoid breadth (MASB); (c), CON vs. braincase height (BRH); (d) forearm length (FA) vs. greatest skull length (GSL), and (e) FA vs. length from canine to upper rear molar (CM3).

Figure 4. Relatively greater inflation of the braincase of left, the holotype of N. holtorum sp. nov. (WAM M.64188), compared with N. gouldi (AM M.51228). Both are adult males with equal GSL.

Figure 5. Frontal view of AM M.39811, male, paratype of N. holtorum sp. nov. showing enlarged dorsal snout mound posterior to the noseleaf. Scale 5 mm.

Figure 6. Distributional records of N. holtorum sp. nov. based onAM and WAM voucher specimens examined (n = 26 localities) and bioregional boundaries of the Interim Biological Regionalization Scheme (IBRS version 7; DSEWPAC, 2012). Regions are: AVW, Avon Wheatbelt; JAF, Jarrah Forests; SWA, Swan Coastal Plain and WAR, Warren.