Rhinolophus stheno, K. Andersen, 1905

Burgin, Connor, 2019, Rhinolophidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 280-332 : 322-323

91 . Lesser Brown Horseshoe Bat

Rhinolophus stheno

French: Rhinolophe sthéno / German: Stheno-Hufeisennase I Spanish: Herradura de Stheno

Other common names: Brown Horseshoe Bat

Taxonomy. Rhinolophus stheno K.Andersen, 1905 ,

“ Selangor, Malay Peninsula . ”

Rhinolophus stheno is currently included in the euryotis group, based on limited genetic data, although its true relationships have yet to be substantiated using taxonomically more inclusive studies. The recently erected species R. microglobosus has typically been included as a subspecies. Monotypic.

Distribution. C & S Vietnam, Malay Peninsula, Sumatra, and Java; distributional limits are still uncertain.

Descriptive notes. Head-body 45-5— 56- 8 mm, tail 12-9-21- 4 mm, ear 15-1- 19- 5 mm, hindfoot 7- 5-10 mm, forearm 43-2-48- 1 mm; weight 6-9— 10 g. Dorsal pelage is reddish cinnamon brown, with a light yellowish-brown base to the hair, or grayish brown; ventral pelage is similar but paler. Ears are small to medium in length. Noseleaf has long, straight-sided lancet with cuneate tip and median septum that is wider than middle pockets; connecting process is rounded and covered in scattered long hairs; sella is narrow with parallel sides or slightly concave sides on middle portion; horseshoe is wide (7-2-10- 4 mm), covering much of muzzle, and has shallow median emargination and conspicuous secondary leaflets; outer ring of horseshoe is darker than paler area around nostrils. Lower lip has three mental grooves. Skull is slender, with subequal zygomatic and mastoid widths (wider than in the Vietnamese Brown Horseshoe Bat,. microglobosus ); anterior median rostral swellings are high and abrupdy elevated (their anterior wall is perpendicular to upper tooth row); posterior swellings are reduced; and rostral profile is posteriorly very concave; sagittal crest is moderately developed; frontal depression is deep (deeper than in the Vietnamese Brown Horseshoe Bat); supraorbital crests are high; interorbital region is very narrow. P2 is large, with a distinct cusp, extruding very slightly from tooth row, which separates C1 and P4; P3 is small and completely displaced, allowing P2 and P4 to touch.

Habitat. Reported in mixed deciduous forests, lowland evergreen forests, agricultural areas, and rubber plantations in Thailand, and in hill forest in Peninsular Malaysia.

Food and Feeding. No information.

Breeding. Pregnant females have been captured in March in Thailand and in MarchMay in Peninsular Malaysia. Lactating females were captured in May-July in Peninsular Malaysia.

Activity patterns. The Lesser Brown Horseshoe Bat is nocturnal, and roosts in caves during the day. Call shape is FM/CF/FM with a peak F recorded at 85-4—88-2 kHz in peninsular Thailand.

Movements, Home range and Social organization. Lesser Brown Horseshoe Bats roost in large colonies.

Status and Conservation. Classified as Least Concern on The IUCNed List. The Lesser Brown Horseshoe Bat is relatively widespread and does not seem to face any major threats at present. It is apparently locally extinct in Singapore.

Bibliography. Bates, Bumrungsri & Csorba (2008d), Csorba & Jenkins (1998), Csorba et al. (2003), rancis (2008 a), Kruskop (2013a), Lane et al. (2006), Soisook (2008), Soisook et al. (2008), Stoffberg et al. (2010), Zhang Lin et al. (2018).

Figures

On following pages: 78. New Guinea Broad-eared Horseshoe Bat (Rhinolophus euryotis); 79. Sulawesi Broad-eared Horseshoe Bat (Rhinolophus tatah; 80. Poso Horseshoe Bat (Rhinolophus belligerator); 81. Bornean Woolly Horseshoe Bat (Rhinolophus proconsulis); 82. Arcuate Horseshoe Bat (Rhinolophus arcuatus); 83. Philippine Forest Horseshoe Bat (Rhinolophus inops); 84. Small Rufous Horseshoe Bat (Rhinolophus subrufus); 85. Large Rufous Horseshoe Bat (Rhinolophus rufus); 86. Intermediate Horseshoe Bat (Rhinolophus affinis); 87. Homfray's Horseshoe Bat (Rhinolophus andamanensis); 88. Croslet Horseshoe Bat (Rhinolophus coelophyllus); 89. Shamel's Horseshoe Bat (Rhinolophus shameli); 90. Vietnamese Brown Horseshoe Bat (Rhinolophus microglobosus); 91. Lesser Brown Horseshoe Bat (Rhinolophus stheno).

Distribution. C & S Vietnam , Malay Peninsula, Sumatra, and Java; distributional limits are still uncertain.