S. Afr. J. Zoo I. 1997,32(2) 37-42 A new adder (Bitis; Viperidae) from the Western Cape Province, South Africa William R. Branch Curator of Herpetology, Port Elizabeth Museum, P.O. Box 13147, Humewood, 6013 South Africa e-mail: [email protected] Received 18 December 1996; accepted 25 February 1997 A new species of small, terrestrial Bitis is described from the Western Cape Province, South Africa. It occurs in sympatry with Bitis comuta and Bifis atropos on the upper slopes and summit of the Cedarberg, and with the lat­ ter on the Swartberg. Features of scalation, colour and body form distinguish the new species from all other southern African Bitis. Its range extends in an arc from the northern Cape Fold Mountains, southwards into the western regions of the Little Karoo, with a possibly isolated population on the Roggeveldberg and Komsberg of the inland escarpment. Within Africa the Viperidae is represented by two well­ two sympatric taxa could be detemnined. One was referable to defined subfamilies; the night adders (Causinae) possessing typical Bitis cornuta (Daudin 1803). The other shared fea­ enlarged colubrid-like head scales and laying eggs; and the tures with Bitis inornata (A. Smith 1838), i.e. greatly reduced Viperinae, which are viviparous and have fragmented head 'horns' (elongated scales in the supraorbital region), low ven­ shields. The latter has undergone a number of adaptive radia­ tral scale counts, and a drab, reddish colouration. He noted tions within the continent, including at least eight species of that the resolution of the taxonomic status of the latter taxon arboreal bush vipers (Atheris) in the rainforests of West and was dependant upon the collection of further specimens. In Central Africa (Spawls & Branch 1995). The most speciose the interim (Branch 1988a; Broadley 1990; Spawls & Branch radiation, however, occurs in terrestrial vipers of the genus 1995), these specimens were treated conservatively as repre­ Biti.. , particularly in the mountains and deserts of the western arid regions of southern Africa. Currently, 14 species, one sentatives of an isolated western population of Bilis inornata, with the stated caveat that they may deserve specific status. extinct, are recognized within the genus, which are tradition­ ) 9 ally grouped into large and small species (Golay, Smith, Burger (1992, 1993) referred Anysberg specimens to this. 0 0 Broadley, Dixon, McCarthy, Rage, Schatti & Toriba 1993; taxon, but also noted a specimen from the reserve that pos­ 2 d Spaw Is & Branch 1995). The former, including B. arietans, sessed small horns and a blotched pattern, and which he con­ e t B. gabonica, B. nasicornis, and B. parviocu/a, are usually sidered may be referable to B. cornuta albanica. a d considered closely related, and a number of interspecific ( Dwarf adders of the genus Bitis are popular in the interna­ r hybrids within the group are known (e.g. B. gabonica x B. e tional pet trade in reptiles, and although protected by Provin­ h arietans, Broadley & Parker 1976; B. nasicornis x B. gabon­ s i cial Ordinances in the Western, Northern and Eastern Cape l ica, Hughes 1968). However, quantitative immunological b provinces, they are known to be involved in illegal wildlife u investigations by Hermann & Jager (1997) indicate that the P traffic. It is evident that some dwarf adders (e.g. the Namaqua e puff adder, B. arietans, is not particularly closely related to h dwarf adder, B. schneideri) are already threatened, in pan, by t & the other large adders. The same authors (Hermann Jager, y illegal collecting for this trade (Branch 1988b). South Africa b 1995) also demonstrated that within the small Bitis species a d Bilis cornuta-inornata subgroup (also including B. atropos is a signator of the Rio Convention on Biodiversity, and also e t and B. xeropaga) was discernable. of the Convention on the International Trade in Endangered n a Species of Wild Fauna and Flora. It is important that new, r Many of the smaller Bitis species have disjunct populations g localized and endemic species be described timeously to e and/or exhibit colour polymorphism that may be geographi­ c n cally consistent. Although some are relatively common in allow for their consideration and possible inclusion in conser­ e c suitable habitat (e.g. the homed adder, Biti.. cauda/is), others i vation legislation and action. l r are often rare and very localized. Among these, the status of Following the acquisition of additional specimens of 'horn­ e d the rare hornless 'many-homed' adders of the southern and less' adders from the Cedarberg, the Little Karoo, and from n u eastern Cape (the Bitis cornuta-inornata complex) has been intermediate localities, and comparison with recently col­ y the source of much taxonomic confusion. For some years iso­ a lected topotypic material of snakes referable to B. inornata w lated specimens of unusual small adders have been collected e (A. Smith 1838), B. atropoides (A. Smith 1846), and B. cor­ t from rocky habitats in the southern and western areas of the a nUia albanica Hewitt 1937, subsequent analysis has allowed a G Cape region in South Africa. They are usually referred to the t fuller analysis of the situation and the recognition of a new e Bilis cornula-inornala complex, In 1987, Branch presented a n i discussion of the early taxonomic history of names applied to species which is described below. A fuller description of var­ b a this complex (Branch 1989). His preliminary analysis of the iation within B. alropoides and B. albanica, and validation of S their specific status, will be presented elsewhere (Branch, in y situation was prompted by the collection of an important b series of specimens from the Cedarberg Mountains) in which prep.). d e c u d o r p e R 38 S. Afr. J. Zool. 1997, 32(2) Character analysis Ventral and subcaudal counts were counted using standard techniques (Dowling 1951). Scale rows were recorded anteri­ orly (ASR, one head length behind the neck), at midbody (MSR), and posteriorly (PSR, one head length in front of the cloaca). Rictals were defined as the number of scales occur­ ring in diagonal series from the angle of the mouth to the pre­ ventrals. Upper and lower labials were counted for both sides (and recorded as the mean of both sides), and care was taken to count smali scales sometimes hidden in the rictal region. The development of elongate scales in the supraocular region (' horns') was recorded as either absent (0), slightly more elon gate than circumoculars (I), obviously elongate (2), and forming a conspicuous tuft of ' horns' (3). Snout-vent length (SVL) and tail length were recorded to the nearest miliimetre. Sex was determined by dissection of the tail region to confirm Figure 1 Bilis rubida n. sp . showing drab colouration. reduced the presence of the hemipenes in males. Hemipenes were supraorbital 'horns', and general habitus (paratype, PEM R12581 , everted and described according to Branch (1986). Paired Cedarberg). Thi s specimen is illustrated in colour in Branch ( 1988a) dorsal blotches are often staggered (particularly on the hind­ and Spawls & Branch (1995). body) and irregularly fu sed. In some populations they are very faint or absent. Blotches were counted from the neck to the cloaca l reg ion, and were only recorded in spec imens hav­ J. van Deventer. SAM 46282, adult female, below Sneeuberg ing a full series of blotches. Hut (= Sneeukop Hut), Cedarberg, Western Cape Province; 32°20'S, 19 20'E; 3219AB; 15 October 1983. Bitis rubida n, sp, (Figure 1) - Red adder Additional material Synonomy (35 specimens) TM 35115, 5 km W of Middelpos (64 km S Bitis inornata FitzSimons, 1946; Branch, 1988a-b; Burger, Calvinia; Visser 1979), Calvinia District; 31 °53'S, 20° 1 t'E; 1992, Burger, 1993; Spawls & Branch, 1995. 3120CC; 3 September 1968; W.D. Haacke. PEM R1197, Por­ B. cornuta albanica FitzSimons, 1962; Broadley, 1990; terville, Western Cape Province; 33 18BB; February, 1959. ) Burger 1992; Burger, 1993. 9 SAM 43874, W of Gydo Pass, Ceres District, Western Cape 0 Bitis corn uta cornuta Haacke, 1975; Visser, 1979. 0 Province; 33°14'S, 19°16'E; 3319AB; March 1976; G. 2 Bitis caudalis (part) Visser 1979. McLachlan. TM 55025, Farm Jakhals Valley, 98 Sutherland d e Bitis cornUia inornata Broadley, 1983. 0 t District, Western Cape Province; 32°26'S, 20 39'E; 3220BC; a Undescribed taxon Branch, 1989. d 28 February 1982; 1. Lochner. TM 57568, RooikJoof, Suther­ ( Bitis cornuta-inornata complex Burger 1993 . 0 r land District, Western Cape Province; 32°26'S, 20 39'E; e Bi/is inornala complex Branch & Bauer, 1995 . h 3220BC; February 1983; J. Lochner. TM 53366, Farm Klip­ s i l pelcraal, 145 Sutherland District, Komsberg, Western Cape b Type material u Province; 32°34'S ,21 °05'E; 3320DB; G. Kunzi. PEM R4350- P Holotype: PEM R12582, adult male with left hemipenis 51 , TM 56632-33, 3 km north of Matjiesfontein, Western e h 0 t everted. Cape Province; 33° 13'S, 20 36'E; 3320BA; J. Lougher. TM y Type locality: Jeep track above Farm Driehoek, Cedarberg 19556, Matjiesfontein, Western Cape Province; 3320BA; b d Mountains, Western Cape Province, South Africa; V.F.M. FitzSimons. PEM R1191, Prince Alfreds Hamlet, e t 32"25'44"S, 19° 12'30"E, alt. 1380 m; 3219AC. Collected 3 Western Cape Province; 3319AD. PEM R6806, Eyerspoort n a September 1986, SA Botha. Private Nature Reserve, Montagu-Barrydale District, Western r g Paratypes: (six specimens) PEM R4457, adult male, near Cape Province; 33 °48'S, 20°41 'E; 3320DC; 24 September e c Crystal Pool, Cedarberg Mountains, Western Cape Province, 1988; R.