Bioacoustics of Hipposideros kunzi

Comparisons with similar species Hipposideros kunzi is one of several Hipposideros species described from the Indo-Malayan region, which superficially resemble H. bicolor and lack supplementary leaflets adjacent to the noseleaf. In peninsular Malaysia and southern Thailand , H. kunzi most closely resembles, and is easily confused with, both H. bicolor and H. pomona . Compared to H. bicolor , H. kunzi has a higher echolocation call frequency ( Table 2 ), is generally smaller in body size ( Table 2 ), and has a shorter but wider skull ( Table 3 and Fig. 9 ). In addition, H. kunzi has a narrower anterior noseleaf ( Holotype : 4.66 mm ) that is slightly curved upwards compared to H. bicolor , which has a wider anterior noseleaf ( 4.94−5.46 mm , n = 5) that is flattened and square in appearance ( Kingston et al ., 2006 ), lighter in color, and has rudimentary supplementary lateral leaflets ( Fig. 9 ). The noseleaf characters, however, are only useful if both species are available for comparison in the field. Based on appearance ( Murray et al ., 2012 : figure S1), echolocation call frequency ( H. pomona : 136.4 –139.4 kHz, n = 3), overall size ( H. pomona length of forearm: 42.7–44.8 mm , n = 3), and skull size and shape ( Fig. 7 ), it is very difficult to distinguish H. kunzi from H. pomona . The main morphological difference between these species is ear height, with H. pomona having a much larger ear compared to H. kunzi : 20.0– 21.5 mm ( n = 3) versus 15.0– 19.5 mm (mean = 17.6 mm — Table 2 ), respectively. Hipposideros pomona and H. kunzi , however, are not closely related based on both mitochondrial and nuclear DNA ( Murray et al ., 2012 ; this study). Despite being sister taxa ( Fig. 2 ), having similar appearance, and overlapping in echolocation call frequencies ( Kingston et al ., 2000 ), individuals of H. kunzi and H. cineraceus -B are easily distinguished using body size ( H. kunzi being larger; Table 2 ) and nose morphology: H. cineraceus -B has a small swelling in its internarial septum ( Fig. 9 ).

Description This is a small to medium-sized hipposiderid bat in the H. bicolor group with a forearm length ranging from 38.8 to 45.6 mm (mean = 42.9 mm ± 0.9), tibia length of 17.1 to 20.6 mm (mean = 18.8 mm ± 0.5), and mass varying from 6.0 to 12.0 g (mean = 8.5 g ± 0.9 — Table 2 ). The dorsal pelage varies from medium or dark brown to bright orange, but is always bicolored with a white base. The ventral pelage ranges from buff or golden, to bright orange ( Fig. 9 ). The wing and tail membranes are dark brown, as are the ears. The ears are large (mean = 17.6 mm ± 0.6) and rounded with a bluntly pointed tip. The noseleaf lacks supplementary lateral leaflets and has an internarial septum that is generally triangular in shape (wider at the base — Fig. 9 ). The posterior and anterior portions of the nose are dark brown-grey in color, while the central part of the noseleaf is more flesh colored. The tail is long (mean = 28.7 mm ± 1.8), extending the full length of the uropatagium. The fifth metacarpal is about 74% of forearm length and the first phalanx of the third digit is about 53% of third metacarpal. Echolocation call frequency of the CF component ranges from 133.2 to 147.5 kHz, with a mean call frequency of 143.1 ± 2.0 kHz ( Fig. 5 and Table 2 ). Hipposideros kunzi has a small and elongate skull with the greatest length of skull (GSL) ranging from 17.69 to 19.13 mm (mean = 18.31 ± 0.33 mm ). The skull is slightly wider across the zygomata (mean = 9.2 ± 0.2 mm ) compared to across the mastoids (mean = 9.2 ± 0.2 mm — Table 3 ). The distal process of the jugal bone is low and not well defined ( Fig. 6 ). The rostrum is well developed with six nasal inflations. The sagittal crest is well developed and is taller more anteriorly. The constriction behind the orbits is well defined and narrower than the rostrum. The upper toothrow is shorter (CM 3 mean = 6.3 ± 0.1 mm ) than the lower (CM 3 mean = 6.8 ± 0.1 mm ). The upper incisor is small and both the upper and lower canines are of moderate size. The upper premolar (P 2 ) is minute and extruded from the toothrow, while the lower premolar (P 2 ) is about half the height of the second premolar (P 4 ). The species is sexually dimorphic with respect to magnitude of certain skull measurements: despite being smaller than females, males have longer and taller skulls and longer canines.