Saturday, October 31, 2015

[Mammalogy • 2015] Rhinolophus francisi | ค้างคาวมงกุฎสามใบพัดเทาดำ • Description of A New Species of the Rhinolophus trifoliatus-group (Chiroptera: Rhinolophidae) from Southeast Asia

 Rhinolophus francisi thailandicus Soisook & Bates, 2015
ค้างคาวมงกุฎสามใบพัดเทาดำ | Thailand Woolly Horseshoe Bat

A new species of woolly horseshoe bat in the Rhinolophus trifoliatus species group is described from Sabah in Malaysian Borneo. Two specimens from Central and West Kalimantan, Indonesia are referred to this species. A fourth specimen from western Thailand is referable to this species but on the basis of ~10% genetic divergence at the cytochrome oxidase-I gene is described as a separate subspecies. Morphologically and acoustically the two subspecies are similar. With a forearm length of 52.90–54.70 mm, a skull length of 24.27–26.57 mm and a call frequency of 49.2–50.0 kHz, the new species overlaps in size and call frequency with the sympatric R. trifoliatus. However, it differs significantly in having a dark noseleaf and a uniformly dark brown pelage, resembling, but being intermediate in size between R. sedulus and R. luctus, which have a skull length of 18.99–20.17 and 26.35–32.07 mm, respectively. It also differs from R. trifoliatus in the shape and size of the rostral inflation. It can be distinguished from R. beddomei (forearm length 55.00–63.44 mm) and R. formosae (forearm length 53.85–62.40 mm), which are endemic to the Indian Subcontinent and Taiwan, respectively, by its relatively smaller body size. Acoustic and genetic data are included in the comparison between the species. Both character states support the conclusions based on morphology. Further surveys in intact evergreen forest together with a re-examination of museum specimens may reveal that this species is widespread in Southeast Asia.

Key words: Borneo, evergreen forest, Malaysia, Indonesia, new species, Rhinolophus, trifoliatus-group, Southeast Asia, Thailand


 Rhinolophus is the single extant genus in the family Rhinolophidae. With at least 87 species cur-rently recognised, it is also one of the most diverse among bat genera and is widely distributed through-out much of the Old World (Simmons, 2005; Yoshiyuki and Lim, 2005; Soisook et al ., 2008; Wu et al., 2008, 2009; Wu and Thong, 2009; Zhou et al., 2009; Taylor et al., 2012). Within the genus, the species have been arranged into several groups based mainly on morphological characters (e.g., shape of the sella, noseleaf and cranial features). This has led to differences of opinion regarding the systematics (e.g., Guillén et al., 2003). None theless, the most widely accepted and most comprehensive review of the Rhinolophidae can be found in Csorba et al. (2003).  

For echolocation, all species of Rhinolophus, and the sister genus Hipposideros, use a high duty cycle, long and narrow band, constant frequency (CF) com ponent, which is adapted for the detection of fluttering insects (Kalko and Schnitzler, 1998). Recent studies of the echolocation characters of the ‘CF bats’ strongly suggest that acoustic characters are useful for species identification (Francis and Haber setzer, 1998; Francis et al., 1999; Kingston et al., 2001; Thabah et al., 2006; Soisook et al., 2008; Hughes et al., 2010; Ith et al., 2011; Taylor et al., 2012; Thong et al., 2012). Moreover, acoustic divergence within species, which may result from the isolation of populations and adaptation due to local environment, can result in genetic drift and in some cases has led to speciation (Kingston and Rossiter, 2004; Chen et al., 2009; Taylor et al., 2012). 

Species in the ‘trifoliatus-group’ are characterised by the presence of a lateral lappet on each side of the base of the sella of the noseleaf. Currently, the group is widely distributed from the Indian subcon-tinent, eastwards to Southeast and eastern Asia, and is represented by five species (Csorba et al., 2003; Simmons, 2005). Until this study, three species of this group were known to occur in Southeast Asia, namely R. luctus, R. trifoliatus and R. sedulus (Francis, 2008) whilst two species, R. beddomei and R. formosae, were thought to be geographically more restricted, recorded from the Indian Subcontinent and Taiwan, respectively (Csorba et al., 2003; Simmons, 2005).

In 2010, R. beddomei was reported for the first time from Southeast Asia based on the morphological characters of a single specimen collected from evergreen forest in western Thailand (Soisook et al., 2010). However, the authors acknowledged that the smaller size of the Thai specimen and the disjunct distribution suggested that additional specimens could confirm this as a different species (Soisook et al., 2010). Fortunately, recent field surveys by a network of researchers in Southeast Asian countries using harp traps in forest habitats has provided additional material. This, combined with a re-examination of a specimen collected from Sabah in 1983 by Charles M. Francis and housed in the Natural History Museum, London makes a more thorough comparative study possible. Francis’s specimen was provisionally identified and labelled R. trifoliatus (see also Payne et al., 1985). 

With a larger sample size and with acoustic and genetic data available to compare with other congeneric species, these specimens have proved to be distinct from other taxa within the group and are described here as a new species.    


Francis’s Woolly Horseshoe Bat | Rhinolophus francisi 
 Soisook, Struebig, Bates & Miguez, 2015

Rhinolophus francisi Soisook, Struebig, Bates and Miguez, sp. nov.

Type locality: Gunung Trus Madi, Sabah, Malaysia (approx. 5º34’N, 116º29’E), at an elevation of about 1,600 m a.s.l.

Etymology: The species is named in honour of Charles M. Francis, who, for many years, has contributed greatly to the taxonomic study of Southeast Asian bats. He also collected the holotype of this species from Sabah, Malaysian Borneo in 1983. The proposed English name is ‘Francis’s Woolly Horseshoe Bat’.

Ecology and conservation notes: In Borneo, the type specimen from Gunung Trus Madi in Sabah was caught in a mist net set in forest on a mountain ridge (C. M. Francis, personal communication). It was found along with seven other bat species during the expedition in 1983 (Sheldon and Francis, 1985). A second individual was captured in undisturbed evergreen forest of Maliau Basin and subsequently released. The specimens from Kalimantan were collected in undisturbed (Tanjung Puting National Park; Gunung Palung National Park), and logged evergreen forest (Nanga Tayap — specimens subsequently released), at sites where both R. sedulus and R. trifoliatus were also present (Struebig et al., 2006). In Thailand, a single specimen from Mae Nam Pha Chi was captured in a harp trap set over a seasonal streamlet surround ed by dense primary evergreen forest at an elevation of 431 m a.s.l. It was found at dawn in the same trap as Nycteris tragata, R. microglobosus, Myotis muricola, Kerivoula papillosa and Phoniscus jagorii (Soisook et al., 2010). The collection sites of Trus Madi, Tanjung Puting and, Mae Nam Pha Chi are legally protected forests, as are survey sites Maliau Basin and Gunung Palung. However, the hunting of mammals may still be a problem across this region, and is considered as major threat to wildlife.

Distribution: Rhinolophus francisi is currently known from only six records; with two records in Sabah, Malaysian Borneo; three in Indonesian Borneo (Kalimantan) and a single record in Thailand (see below). The species may be distributed more widely in these regions, but has been rarely captured despite extensive surveys. Genetic data also suggest that this species is likely to occur in Vietnam, although this needs to be confirmed.

Thailand Woolly Horseshoe Bat | Rhinolophus francisi thailandicus
 Soisook and Bates, 2015

Rhinolophus francisi thailandicus Soisook and Bates subsp. nov.

Holotype: PSUZC-MM.2008.51 (field number PS080420.6), adult male, body in alcohol, skull and baculum extracted, collected by Pipat Soisook, Tuanjit Srithongchuay, Piyawan Niyomwan and Priwan Srisom, on 20 April, 2008.

Type locality: Pu Nam Ron Stream, Mae Nam Pha Chi WS., Ratchaburi Province, Western Thailand (13º15’N, 99º2’E, 431 m a.s.l.).

Etymology: The subspecific name, thailandicus, means ‘of or from Thailand’ indicating where this subspecies is found. The proposed English name of the subspecies is ‘Thailand Woolly Horseshoe Bat’.

FIG. 1. Face, noseleaf and ventral pelage (a, b), sella (c) and dorsal pelage (d) of Rhinolophus francisi sp. nov., ♂PSUZC-MM.2008.51 (holotype of thailandicus subsp. nov.) from Thailand. Not to scale

ค้างคาวมงกุฎสามใบพัดเทาดำ Rhinolophus francisi เป็นค้างคาวขนาดใหญ่ ขนาดลำตัวใกล้เคียงกับค้างคาวมงกุฎสามใบพัดแต่ต่างกันตรงที่ สีของแผ่นจมูก หู ปีกและขนบางส่วน ของค้างคาวมงกุฎสามใบพัดเป็นสีเหลือง ขณะที่อวัยวะต่างๆ เหล่านี้ของค้างคาวมงกุฎสามใบพัดเทาดำ จะมีสีเทาอมน้ำตาล เป็นค้างคาวหายาก พบกระจายพันธุ์ได้ในประเทศมาเลเซีย (รัฐซาบาห์) อินโดนีเซีย (จังหวัดกาลีมันตันตะวันตก และจังหวัดกาลีมันตันกลาง) และไทย (จังหวัดราชบุรี) โดยก่อหน้านี้เมื่อ ปี ค.ศ. 2010 ค้างคาวชนิดนี้เคยได้รับการรายงานการพบว่าเป็น new record ของค้างคาวชนิด Rhinolophus beddomei เป็นครั้งแรกในประเทศไทย แต่จากการศึกษาเพิ่มเติมอย่างต่อเนื่องหลังจากนั้นก็พบว่าแท้จริงแล้วเป็นค้างคาวชนิดใหม่ของโลก และเป็นชนิดเดียวกับตัวอย่างที่พบในบอร์เนียว แต่ประชากรที่พบในประเทศไทยนั้นมีความแตกต่างทางพันธุกรรมจากตัวอย่างในบอร์เนียว จึงได้ตั้งชื่อเป็นชนิดย่อย ชื่อว่า Rhinolophus francisi thailandicus

Pipat Soisook, Matthew Struebig, Sephy Noerfahmy, Henry Bernard, Ibnu Maryanto, Shiang-Fan Chen, Stephen J Rossiter, Hao-Chih Kuo, Kadambari Deshpande, Paul J. J. Bates, Dan Sykes and Roberto Portela Miguez. 2015. Description of A New Species of the Rhinolophus trifoliatus-group (Chiroptera: Rhinolophidae) from Southeast Asia.
Acta Chiropterologica. 17(1): 21-36  DOI: 10.3161/15081109ACC2015.17.1.002