Descriptions of new Borneo sharks and rays 77 $QHZVSHFLHVRIZHGJH¿VKRhynchobatus springeri 5K\QFKREDWRLGHL5K\QFKREDWLGDH IURPWKH:HVWHUQ3DFL¿F Leonard J.V. Compagno1 & Peter R. Last2 1 Shark Research Center, Iziko – Museums of Cape Town, Cape Town 8000, SOUTH AFRICA 2 CSIRO Marine & Atmospheric Research, Wealth from Oceans Flagship, GPO Box 1538, Hobart, TAS, 7001, AUSTRALIA ABSTRACT.—$QHZVSHFLHVRIZHGJH¿VKRhynchobatus springeri sp. nov. is described from specimens FROOHFWHGIURPWKH,QGR±0DOD\UHJLRQZLWKDFRQ¿UPHGUDQJHH[WHQGLQJIURPWKH*XOIRI7KDLODQGVRXWK to Java, and possibly westward to at least Sri Lanka. It is a medium-sized species to about 215 cm TL, with males reaching adulthood at about 110 cm TL. Rhynchobatus springeri closely resembles R. palpebratus in body shape and having a dark, eye-brow like marking on its orbital membrane, but differs from this species in having a lower vertebral count (113–126 vs. 130–139 total free centra), a broader preorbital snout, and more rows of white spots on the tail of adults. Other Rhynchobatus species in the region attain a much larger adult size, and have a relatively narrower snout and much higher vertebral counts. A revision of the group LVQHHGHGWR¿QGPRUHXVHIXO¿HOGFKDUDFWHUV Key words: Rhynchobatidae – Rhynchobatus springeri±%URDGQRVH:HGJH¿VK±QHZVSHFLHV±:HVWHUQ 3DFL¿F PDF contact: [email protected] INTRODUCTION Rhynchobatus by various authors, but only two, the West African R. luebberti Ehrenbaum, 1914 and the Indo– The genus Rhynchobatus Müller & Henle, 1837 :HVW3DFL¿FR. djiddensis (Forsskål, 1775), are generally comprises several species of moderate-sized to giant recognised as valid and most of the remaining taxa have (attaining between 0.8 and more than 3 m total length) been synonymised with R. djiddensis (Garman, 1913; shark-like batoids. They belong in the monotypic family Fowler, 1941). Compagno & Last (1999) gave a brief 5K\QFKREDWLGDH DFFRUGLQJ WR WKH FODVVL¿FDWLRQ RI UHYLHZRIWKH:HVWHUQ&HQWUDO3DFL¿FVSHFLHVDVPHPEHUV McEachran et al. (1996), removing them from family of the family Rhinidae, including a key to species in the Rhinidae and a single species Rhina ancylostoma Bloch area and brief accounts and illustrations of R. australiae & Schneider, 1801. Following FAO usage (Stehmann, (Whitley, 1939), R. cf. laevis (Bloch & Schneider, 1801), 1981; Compagno & Last, 1999), Rhynchobatus species are and two undescribed species, referred to as R. sp. 1 and WHUPHGµZHGJH¿VKHV¶EHFDXVHRIWKHLUGLVWLQFWLYHZHGJH R. sp. 2. More recently, Compagno & Last (2008) described VKDSHG GLVFV RWKHU QDPHV LQFOXGH JLDQW JXLWDU¿VKHV a new species, Rhynchobatus palpebratus, from the Indo– ZKLWHVSRWWHG JXLWDU¿VKHV DQG VLJQL¿FDQWO\ VKDUN¿Q Malay Archipelago, and provisionally recognised 6 other JXLWDU¿VKHV :HGJH¿VKHV DUH ZLGHVSUHDG DQG FRPPRQ taxa as valid: Rhynchobatus australiae Whitley, 1939 in inshore tropical waters of the Eastern Atlantic, Indian from Australia, Thailand, Philippines, Singapore, Taiwan, 2FHDQDQG:HVWHUQ3DFL¿F and Indonesia; Rhynchobatus djiddensis (Forsskål, 1775) from the western Indian Ocean, including southern Members of the genus Rhynchobatus include some of Africa, Mozambique and the Red Sea; Rhynchobatus the largest species of rays, with Rhynchobatus djiddensis laevis (Bloch & Schneider, 1801) from Zanzibar, the attaining a total length of 3 m and R. luebberti reaching Arabian Sea, Oman, the Persian Gulf, India, Sri Lanka, a weight of at least 227 kg. Two other Rhynchobatus and Bangladesh; Rhynchobatus luebberti Ehrenbaum, species grow to at least 2–3 m length. Müller & Henle 1914 from tropical West Africa, including Mauritania to (1837, 1841) recognized only a single species in the genus Congo and Angola; Rhynchobatus sp. 1 (Compagno & Rhynchobatus, R. laevis (Bloch & Schneider, 1801). Last, 1999), only known from Singapore and Java; and Eleven species and a subspecies have been referred to Rhynchobatus sp. 2 (Compagno & Last, 1999) found in 78 WKH:HVWHUQ3DFL¿FLQFOXGLQJWKH3KLOLSSLQHV7KDLODQG WKH FDXGDO ¿Q EXW IRU SXUSRVHV RI FRQVLVWHQF\ FRXQWV Sarawak, Singapore, and Java. DUHGHOLPLWHGDQWHULRUO\DWWKHXSSHUFDXGDO¿QRULJLQDV in sharks (Springer & Garrick, 1964). Counts presented :HGJH¿VKHVDUHFRPPRQO\FDXJKWDVE\FDWFKRIGHPHUVDO here include the numbers of centra in the synarcual LQVKRUH¿VKHULHVZKHUHYHUWKH\RFFXUDQGDUHLPSRUWDQW element, and the MP centra, DP centra, DC centra, total FRPPHUFLDOO\IRUWKHLUH[FHOOHQWÀHVKDQGYHU\YDOXDEOH free centra, and total centra; centrum-free segments and ¿QVZKLFKDUHFXUUHQWO\LPSRUWDQWLQWKHRULHQWDOVKDUN total segments were not included as some of these counts ¿QWUDGH7KHLQWHQVH¿VKHULHVSUHVVXUHRQZHGJH¿VKHV SURYHGGLI¿FXOWWRREWDLQ and minimal biological data on any of the species, makes for concern about their conservation status; currently no In Rhynchobatus, as in most modern elasmobranchs VSHFLHVLQWKHIDPLO\LVSURWHFWHGDQG¿VKHULHVDUHODUJHO\ or neoselachians (Compagno, 1973, 1977, 1988, 1999, unregulated. In southern Africa and tropical Australia, 2003), there are three basal cartilages to the pectoral- ZHGJH¿VKHVDUHVRXJKWDVJDPH¿VKHVE\VSRUWVDQJOHUV ¿Q VNHOHWRQ WKH DQWHULRU SURSWHU\JLXP LQWHUPHGLDWH because of their great size and strength, and powerful mesopterygium, and posterior metapterygium, which response when hooked. EHDUV PRVW RI WKH SHFWRUDO¿Q UDGLDOV Rhynchobatus (and various other batoids) have a space between the The following paper describes one of the undescribed mesopterygium and metapterygium where `neopterygial’ ZHGJH¿VKHVRhynchobatus sp. 2, a broad snouted form radials articulate directly with the synarcual. The with a low vertebral count. propterygium of Rhynchobatus is a single, unsegmented cartilage with its front end terminating behind the nasal capsules; anterior to the propterygium are 1–8 METHODS free propterygial radials suggesting that a segmented propterygial axis, such as that present in other batoids, may Proportional dimensions, expressed as percentages of have been lost in Rhynchobatus. The propterygium itself total length, are given in Table 1. External measurements has 16–26 radials, the mesopterygium about 5–7 radials, of Rhynchobatus specimens are based on batoid the neopterygial space on the scapulocoracoid about 4–6 measurements proposed by Bigelow & Schroeder (1953), radials, and the metapterygium 21–29 radials. Counts Hubbs & Ishiyama (1968), Compagno & Roberts (1982), presented include free, propterygial, mesopterygial, Compagno & Randall (1987) and Randall & Compagno neopterygial, metapterygial, total basal radials (excluding (1995), and the shark measurements of Compagno (1984, free radials), and total radials. Cranial morphology of the 2001). Terminology for enlarged dermal denticles or new Rhynchobatus species is not considered in detail thorns is based on Hubbs & Ishiyama (1968). Vertebral here but we note that Rhynchobatus species differ in the FHQWUD SHFWRUDO¿Q UDGLDOV DQG FUDQLD ZHUH H[DPLQHG shape of their rostral appendices, and by the position of and meristic details counted from radiographs including the anterior ends of the antorbital cartilages relative to all paratypes and 8 non-types (see also Compagno & the anterior ends of the nasal capsules. Last, 2008). The vertebral column of Rhynchobatus is PRUHGLIIHUHQWLDWHGWKDQLQVKDUNVDQGLVFODUL¿HGKHUHLQ Morphometric data in the description includes information a group of vertebrae behind the cranium are fused to on 6 specimen lots that were not included in the type form a large cervical synarcual element (Garman, 1913; series as their whereabouts is presently unknown, while Compagno, 1973, 1988, 1999, 2003) containing from another two lots (SU 69893 and SU 69894) still require 25–34 segments; the synarcual element has an anterior resolution as they contain multiple specimens. Also, centrum-free region of 13–21 segments and a posterior 8610 DSSDUHQWO\FLWHGE\/-9&LQKLVGDWD¿OHV region with 11–16 embedded centra. The number of as USNM 75877 but matching USNM 72480 in size, synarcual segments is determined by counting the VH[DQGORFDOLW\GDWD LVFRQ¿UPHGWREHDVSHFLPHQRI synarcual centra and the corresponding spinal nerve the new species (by PL), based on photos facilitated by foramina and canals in the anterior centrum-free region on Jerry Finan, Jeffrey Williams and Sandra Raredon at the properly exposed, high-resolution radiographs; it is often USNM. not possible to count the centrum-free region in some VSHFLPHQV SDUWLFXODUO\ QHZERUQ DQG SRRUO\ FDOFL¿HG Material discussed in this manuscript is deposited widely individuals, although synarcual centra are usually visible. in ichthyological collections following Leviton et al. Posterior to the synarcual, the vertebral column can be (1985): Australian National Fish Collection (CSIRO), subdivided into monospondylous precaudal (MP) centra California Academy of Sciences (CAS), Hokkaido in the trunk, diplospondylous precaudal (DP) centra in the University Museum (HUMZ), Marine Reference precaudal tail, and diplospondylous caudal (DC) centra Collection at Institut Penyelidikan Perikanan Sarawak LQWKHFDXGDO¿Q7KH03FHQWUDKDYHYHU\ORQJULEVWKDW (IPPS), Natural History Museum of Los Angeles County are reduced posteriorly before the transition to DP centra, (LACM), Rijks Museum voor Natuurlijke History (now = in which the centra suddenly become smaller and two National Museum of Natural History, Naturalis (RMNH), per myomere. The DC centra have strongly expanded National Museum of Natural History (USNM), and QHXUDODQGKDHPDODUFKHVPRGL¿HGDVSWHU\JLRSKRUHVIRU Zoological Museum Hamburg (ZMH). Also includes two Descriptions of new Borneo