Vol. 6, 1-26 I June 1995 Asiatic Herpetological Research pp. Systematics of the Vipers of the Caucasus: Polymorphism or Sibling Species? 1 2 4 AND GORAN NILSON , BORIS S. TUNIYEV , NIKOLAI ORLOV^, MATS HOGGREN CLAES ANDREN 1 'Department of Zoology, Goteborg University, Sweden 2 Caucasian State Biosphere Reserve, Sochi, Russia ^Zoological Institute, Russian Academy of Sciences, St. Petersburg, Russia ^Department of Genetics, University of Uppsala, Russia Abstract. -Inter- and intramorphological variation were examined in sympatric and allopatric polymorphic and monomorphic populations of the Vipera ursinii and Vipera kaznakovi complexes. The alpine Vipera dinniki populations in upper Great Caucasus show a pronounced, and to a certain extent geographical, and 'ursinii' polymorphism. Color patterns include among others 'kaznakovi', 'tigrina', 'berus', 'bronze', litter in certain types. Several of these patterns can be represented within the same populations. Vipera This last dinniki is sympatric with the Caucasian representative of the Vipera ursinii complex in some areas. taxon shows a similar degree of polymorphism, which is unique for this complex, and due to morphological - and molecular distinction, we consider it to be a Caucasian evolutionary species within the ursinii complex Vipera lotievi sp.n. V. V. lotievi Key Words: Reptilia, Squamata, Viperidae, Vipera dinniki, V. kaznakovi, V. ursinii, renardi, sp.n., Caucasus, Russia, Georgia, taxonomy, morphology, polymorphism. Introduction synonym of V. kaznakovi until Vedmederja et al (1986) recognized it as a separate The taxonomy of the vipers of Caucasus species inhabiting alpine and subalpine has for a long time been confusing and meadows in the Caucasus, and thus contradictory. According to the traditional restricting V. kaznakovi to lower altitudes in moist view a single species, Vipera kaznakovi, is western Caucasus and adjacent distributed in the moist and warm lowlands lowland habitats along the eastern Black Sea of the western Caucasus as well as in the coast. Thereby the problem of the gradual in the mountain valleys towards the east. In the transformation from V. kaznakovi east the habitat is drier and along the range west of the Caucasus to V. ursinii in the east the Caucasus the vipers gradually change toward Vipera is restricted to high ursinii in appearance. In the east Caucasus populations, now including V. dinniki and is well defined only this last viper was supposed to occur. V. ursinii. Vipera kaznakovi Thus there seemed to be a somewhat clinal and restricted in distribution, and transformation from "pure" V. kaznakovi in geographically separated from all the other the west to "pure" V. ursinii in the east. viper species in the region. Vipers from the intermediate region could be difficult to determine. Within the same The complex history of nomenclature clarified to a locality some specimens look like V. and taxonomy has been great kaznakovi, other ones are more like V. part in some recent publications (see Orlov ursinii, while still some can be intermediate. & Tuniyev, 1986; 1990), together with hypotheses about the phylogeny of this Nikolsky (1913) separated the alpine group. Concurrently the need of genetic populations into the taxon Vipera berus studies was stressed, and this has led to the dinniki, which was based on alpine present work where we in a series of papers specimens of the conventional V. kaznakovi intend to clarify the taxonomy and evolution from high altitudes in the western Caucasus of the vipers of this region. The work is (Malaya Laba River- terra typica restricta planned to have a broad perspective and Svanetia) as well as from other places. including phenetic and phylogenetic The name dinniki was long considered as a analyses, habitat choice, niche-breadth, and © 1995 by Asiatic Herpetological Research Vol. 6, p. 2 Asiatic Herpetological Research June 1995 reproduction. Different methods take Altogether about 300 preserved or live different time and in this first paper the specimens of vipers from the Caucasus and morphology is reexamined, based on adjacent regions have been seen during the available material in Museum collections and study. Joint field trips were made in freshly collected material from a number of different parts of the Caucasus in 1990 and new places, as well as on inheritance of 1992, but two of us (Tuniyev and Orlov) color pattern. Genetic structures based on have performed extensive research in the phenetic analyses of allozyme data are also region prior to that. For morphometric presented. studies 183 preserved snakes within the ursinii and kaznakovi complexes have been The morphological distinction between examined more carefully, and for most of Vipera dinniki and V. kaznakovi has been these specimens 30 different items of data presented elsewhere (Orlov and Tuniyev, have been collected. This information was 1986; 1990) and will not be repeated in this used, down to population level, in study. In the present paper we are focusing morphological descriptions, taxonomical on patterns of morphological and molecular analyses and conclusions about variation within and between the different zoogeography and range overlap. populations in the Caucasus, and the Inheritance of color pattern was studied taxonomy of these populations. based on 23 pregnant females and their offspring. Material and Methods Data collected were: total length and tail The work has mainly been a study of length; number of preventrals, ventrals, variation in external morphology, allozymes subcaudals, anterior and mid-body dorsal and reproduction in order to reveal patterns scale rows, apical plates, supralabials, of sympatry and sibling species. Additional sublabials, circumocular scales, loreals, genetic studies will follow when material second chinshields, mentals, crown scales becomes available in suitable samples (=intercanthals + intersupraoculars), and (presently delayed due to political reasons). zig-zag windings in dorsal band. Further Thus live and preserved museum material rostral index (height/breadth) and head index has been examined concordantly with (breadth/length) were calculated. Division studies of reproduction in the laboratory. of parietals, frontal, and nasalia was noted, as was the color of dorsal and ventral sides, and iris (in live specimens). Further, upper Additional preserved material used in preocular size; and head, labial and lateral this study originates from the Natural body patterns, as well as distinctiveness of History Museum in Goteborg (GNM); canthus rostralis were examined. Details Dipl.-Biol. F. J. Obst, Staatliches Museum about these methods are found in Nilson and fur Naturkunde, Dresden (MTKD D); Aram Andren (1986). Agasian, Zoological Institute, Academy of Sciences, Eriwan, Armenia. Abbreviations for museums as used in the text are: CNR- Morphologylphenetics Caucasian State Biosphere Reserve, Standard errors accompanying mean Collection of Boris Tuniyev at Yew-box character ratios were used as relative Groove, Sochi; GNM- Goteborg Natural measurement of dispersion. For the History Museum, Goteborg; MTKD- of intra- and Staatliches Museum for Naturkunde, analysis interpopulational morphological variation (phenetic analysis) Dresden; ZIEr- Zoological Institute, the samples were divided into subsamples Academy of Sciences, Eriwan; ZIG- depending on questions raised. Thus Department of Zoology, University of besides an analysis of morphological Goteborg; Goteborg- (authors' collection, variation also a pattern confirming or which later will be incorporated in GNM); rejecting the present taxonomic pattern could ZIN- Zoological Institute, Academy of be achieved. This pattern could also be Sciences, St. Petersburg. June 1995 Asiatic Herpetological Research Vol. 6, p. 3 if else is TABLE 1 . Number of specimens used in the genetic analyses and localities (Russia nothing stated) for the examined taxa. kaznakovi: 1. Dagomys, north of Sochi. Six specimens. 2. Rudorova, inland locality, 900 m alt. Four specimens. dinniki: 3 . Fisht/Oshten, the westernmost locality of the main Caucasus range. Seven specimens. 4. Lake Impsi, 1,980 m. alt., at a tributary to the Little Laba River on the northern slope of the main range. Seven specimens. 5 . Aishkha-II on the southern slope of the main range. Three specimens. 6. Lake Kardyvach at upper Mzymta River on the southern slope of the main range Seventeen specimens. lotievii: 7. Armkhi, Checheno-Ingushetia. 2,000 m altitude. Seven specimens. berus: 8. Uppsala (terra typica), Sweden. Eleven specimens. eriwanensis: 9. pooled sample from Asbua and Cildir, Kars, east Turkey; and Sevan, Armenia. Six specimens. supported or rejected by the parallel among the eight Caucasus populations biochemical studies. Thereby it is possible studied (see Table 1, for locality data and to state or reject the occurrence of sample sizes). A potential risk of sampling convergent or parallel evolution, i.e. sibling error due to syntopic occurrence of two taxa species. may be avoided by testing observed genotype distribution within a locality Estimation of the different color pattern against Hardy-Weinberg expectations (see frequencies in local populations was based results). Fresh or frozen tissues (-75°C) on observations during the field work. from liver and skeletal muscle were Small museum samples collected by others homogenized in distilled water. The extracts were not included in this analysis due to were centrifuged for 10 min at 10,000 rpm uncertainty of randomness in sampling and 4°C and