Jacobsen, NHG

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318 A new subspecies of Typhlosaurus lineatus Boulenger 1887 (Reptilia: Scincidae) from Venda, Southern Africa N.H.G. Jacobsen Division of Nature Conservation, Transvaal Provincial Administration. Private Bag X209, Pretoria, 0001 Republic of South Africa Received 1 October 1986; uccepted 5 June 1987 A new subspecies of Typhlosaurus lineatus, is described. It differs from the other taxa in either colour, a single supraciliary, or lower total ventral scale counts. Geographical isolation is apparent. 'n Nuwe subspesie van Typhlosaurus lineatus word beskryf. Oit verskil van die ander taksa in ten minste twee van die eienskappe soos kleur, 'n enkele suprasiliare skub en laer totale ventrale skubteliings. Geografiese afsondering is oak duidelik. Introduction The genus TyphlosauTlls Wiegmann. 1834 has recently been revised by Broadley (1968). He lists 12 species and subspecies including three subspecies of Tlinealus. One of these, T. I. subtaenialus Broadley. differs from the nominate race by having a lower ventral count as well as being striped above and below. Occasional near uniform melanistic individuals arc known. Haacke (1986) described a new Typhlosaurus species from the Western Cape and discussed phylogenetic rclationships of the members of the genus including T. Iinealus which arc pertinent to thb paper. During a survey of the reptiles and amphibians of the Transvaal which has been in progress since 1978, a series of nine specimens related to T. lineatus was found. These differ from T I. linealus Boulenger. TI. sublaenialus and T. I. jappi Broadley in scalation, size, colour and geographic separation and are therefore described as a new subspecies. In addition a further series of 10 T I. sublaeniafus were caIIected during the survey which arc used during the following analysis, incorporating data from Broadley (1968). Systematics Typhlosaurus lineatus richardi subsp. nov. (Figure 1) Type material Nine specimens. collected by the author and R.E. Newbery at the type locality. Holotype: TM 59066, adult male. Allotype: TM 59067, adult female. Paratype.<: TM 59063-59065; 59068-59071 (five males and two females). TM 59063 caIIected as for holotype. TM 59064. 59071 collected 24 May 1979, all others collected 27 June 1981. The type specimens were deposited in the Transvaal Museum Collection, Pretoria. S.-Afr.Tydskr.Dicrk. 1987, 22(4) Type locality In sandveld 4 - 5 km north of Tshamavhudzi peak 22" 37'S/3D" 31 'E, (2230 DA), Republic of Venda. Southern Africa. (Figure 2). Etymology The subspecies is named for Richard E. Newbery for his enthusiasm and assistance during the survey without which much less would have been accomplished. Diagnosis T I. richardi differs consistently from the other three taxa in having one supraciliary. In addition it differs from both the nominate form and T I. jappi in having a lower total ventral count. T. I. richardi differs also from T. I. subtaeniatus in being white below as opposed to the striated ventrals of the latter. Description Holotype. TM 59066 (Figure I). adult male. Snout/vent A '---Figure 1 Head 5calation of Typhlosaurus I. richardi subsp. nov. (TM 59066. holotypc); (A) right lateral. (R) dorsal and (C) ventral view. CS; chin shield, F: frontal, L; lorcal. LL: lower labial, M: mental, N: nuchal. 0: ocular. P: parietal, PO: postocular, PreO: preocular, R: rostml. SO: supraocular, SuhO: subocular, SC: supraciliary, T: temporal, UL: upper labial. Reproduced by Sabinet Gateway under licence granted by the Publisher (dated 2009).S.Afr.J.Zool. 1987,22(4) length 131 mm; tail 23,5 mm; mass 2,45 g. Snout strongly depressed and pointed: rostral large, and approximately half the length of the head; snout flattened below with a sharp horizontal cutting edge. Nostrils pierced in the rostral about one third back, and connected with the posterior border by a long single horizontal suture on each side. Prefrontal broader than long. Five shields (upper labials, loreals and prefrontal) in contact with rostral. The anterior supraciliary has fused with the anterior supraocu!ar. Posterior supraciliary very small and in contact with the posterior supraocular and the postocular. Preocular in contact with the loreal. Prefrontal in contact with loreais, supra oculars and frontal. Frontal subpentagonal. Subocular in contact with first and second upper labials. Four upper labials. Parietals meet behind the frontal. Four chin shields border the mental. Lower labials, three. Mid-body scale rows 14, ventrals 161. subcaudals 30. Tail tapering to a pointed tip. Colouration Golden yellow above with four distinct longitudinal stripes extending the full length of the body to the tail tip, while the lateral stripes, one on each side, arc indistinct and end near the vent. Venlrum white. Variation Allotype TM 59067, adult female. Head-body length 131,5 mm. Similar in other respects to the holotypc. Ventrals 168. Tail truncated. Paratypes Most specimens arc similar to the holotype, the exceptions being TM 59063 which has three upper labials and the subocular on one side fused with the postocular; TM 59071 has seven shields, namely the first upper 319 labials, loreals, prefrontal and the frontonasals, bordering the rostral; TM 59065 has only three shields in contact with the mental. Scales, 14 at mid-body; ventrals 160 - 168, (x ~ 163,44): subcaudals 26 - 30 (x ~ 29,14). Sexual dimorphism is apparent in the number of ventrals with males 160 - 164 (x ~ 161,67, n ~ 6) and females 166 - 168 (x ~ 167,00, n ~ 3). In two specimens TM 59063, 59067, tail autotomy was observed. C%uration All specimens similar to holotype. Size Largest, TM 59066 (Holotype), although TM 59063 has a SN length of 133,5 mm, with tail truncated. Tail 15,2% (14,28 - 15,33) of total length. Reproduction TM 59067 is gravid with two embryos in an early developmental stage. Habitat All specimens were found under rotting logs in deep aeolian sand on the northern slopes of the eastern Soutpansberg. Distribution Known from a limited area in northern Venda, (Figure 2) and possibly relict. Discussion T. I. richardi is the most eastern form of Typhlosauru.< lineatus. The distribution of the nominate form is restricted to the arca of Kalahari sand in Botswana, South West Africa (Namibia) and the northern Cape Province. T. I. jappi occurs to the north of it, in western Zambia and eastern Angola, while T. I. subtaeniatus is a Figure 2 Distribution of T. J, n'chardi. and T. I. subtacniatus ., Reproduced by Sabinet Gateway under licence granted by the Publisher (dated 2009).320 S.-Afr.Tydskr.Dierk. 1987,22(4) Table 1 Comparative data of the four subspecies of Typhlosaurus lineatus Number Ventral" Subcaudals Largest Tail length Number of head Supra- Si7C (total as % of of lines Subspecies N ,hiclds cilliarie!'. Range Mean Range Mean lenglh)(mm) total length on body lineatus "# 229 . 37 1-2 176-193 183,~ 26-35 29,9 1~2,0 11,0-15,0 4-8 subtacniatu.'i 0; 15 37 2 102-179 169,7 26-30 27,3 154,0 11,7-14,2 8 jappi .. 43 37 2 176-186 181,5 22-27 24,4 213,0 10,3-13,6 2-4 richard; 9 35 160-168 163,4 26-31 29,1 154,5 14,3-15,3 4-{i "'Data from Broadley (1968) with sub!'.p. sublaenialu.~ !.upplcmented by specimens collected by the author. localized form of the north-western Transvaal, (Broadley 1968). T. I. richardi resembles the nominate form in its colouration. This is of interest as T. r subtacniatw,which has a striated ventrum is found between the two. Comparative data for the four subspecies are provided in Table 1. Although Table 1 indicates that T. /. lineatus may only have a single supraciliary this is an irregular event, occurring only rarely (twice in 225, Broadley 1968). Similarly the number of ventrals in T. I. subtaeniatus ranges from 162-179, but the lowest count is that of an isolated individual (TM 59072, Farm Smithfield 456 MS, 2229CD), most others ranging from 167-173. Broadley (1968) discusses well marked evolutionary trends in the genus Typhlosaurus which include a reduction in the number of dorsal head shields, an increase in the number of ventrals, and progressive attenuation of the body. In only one of these respects, (a decrease in the number of head shields) does this new subspecies appear to be more advanced than the other three subspecies. The nominate form, however, does occasionally show head scalation reduction, Broadley 1968). T. I. richardi has the lowest number of ventra Is of the four subspecies and in this character is closer to Broadley's ancestral form. Both T. I. richardi and T. I. subtaeniatus are smaller than the nominate form and T. I. jappi. The former also has a longer tail than that of the other subspecies although approached in this respect by the nominate form. Recent anatomical studies (Rieppel 1982) indicate that different skull structures altered at different rates in different species independently of one another. He also pointed out that external features of squamation do not evolve in concert with internal characteristics of the skull. Rieppel (1982) therefore does not agree with Broadley's (1968) hypothesis and considers T. I. lineatus to be the most primitive typhlosaur he examined. How close T. I. richardi is to the nominate fonn is therefore difficult to assess. It is similar in respect of some external features, as is T I. jappi (Table 1). Broadley's hypothesis of the distribution of Typhlosaurus is that during interpluvial periods T. linealus was able to extend its range eastwards. During the following pluvial period the ranges shrank leaving isolated populations in northern Venda, north-western Transvaal and in western Zambia. This is substantiated by the presence of Mabuya homaloccphala deprcs.<a (Peters) at the same locality as T. I. richardi. The former ,being a coastal species, migrated inland along the dry Limpopo valley and remained separated from the nearest other population in the eastern Kruger National Park when the intervening sands were washed away during subsequent pluvial periods. T. I. richardi therefore represents an apparently relict population which, on account of distinct morphological differences, is considered a taxon distinct from other related taxa. Acknowledgements I am especially grateful to Richard Newbery for his support and assistance during the survey. Mr W.O. Haacke is thanked for assistance in preparing this paper. The Director of Nature Conservation is thanked for permission to publish this article. References BROADLEY. D.G. 1968. A revision of the African genus Typhlosaurus Wiegmann (Sauria:Scincidae). Arnoldia 3(36): 1-20. HAACKE, W.D. 1986. Description of a new species of Typhlosaurus Wiegmann. tR34 (Reptilia: Scincidac) from the west coast of Southern Africa, with new records of related species. Ann. Transvaal Mus. 34(9): 227-235. RIEPPEL, O. t982. The phylogenetic relationships of the genus Acontophiops Sternfeld (Sauria: Scincidae), with a note on mosaic evolution. Ann. Tran.svaal Mus. 33 (12): 241-257. Reproduced by Sabinet Gateway under licence granted by the Publisher (dated 2009).

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A new subspecies of Typhlosaurus lineatus Boulenger 1887 (Reptilia: Scincidae) from Venda, Southern Africa

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A new subspecies of Typhlosaurus lineatus Boulenger 1887 (Reptilia: Scincidae) from Venda, Southern Africa

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