Anais da Academia Brasileira de Ciências ISSN: 0001-3765 [email protected] Academia Brasileira de Ciências Brasil Vanzolini, Paulo E.; Calleffo, Myriam E.V. A taxonomic bibliography of the South American snakes of the Crotalus durissus complex (Serpentes, Viperidae) Anais da Academia Brasileira de Ciências, vol. 74, núm. 1, março, 2002, pp. 37-83 Academia Brasileira de Ciências Rio de Janeiro, Brasil Available in: http://www.redalyc.org/articulo.oa?id=32774105 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Anais da Academia Brasileira de Ciências (2002) 74(1): 37–83 (Annals of the Brazilian Academy of Sciences) ISSN 0001-3765 www.scielo.br/aabc A taxonomic bibliography of the South American snakes of the Crotalus durissus complex (Serpentes, Viperidae) PAULO E. VANZOLINI and MYRIAM E.V. CALLEFFO 1Museu de Zoologia, Universidade de São Paulo, Cx. Postal 42694, 04299-970 São Paulo, SP, Brasil 2Instituto Butantan, Laboratório de Herpetologia, São Paulo, SP, Brasil Manuscript received on October 26, 2001; accepted for publication on November 9, 2001; contributed by Paulo E. Vanzolini ABSTRACT A survey is made of the taxonomic literature on South American rattlesnakes (genus Crotalus, family Viperi- dae). Two main areas are emphasized: the attribution of the names proposed in the eighteenth century by Linnaeus and Laurenti, and the current scheme of division in subspecies. The attribution of names is examined based on the original descriptions and on relevant previous and con- temporary literature. The presently adopted scheme, proposed by Klauber (1941, 1972) is found not entirely satisfactory, but reasonable enough – besides being hallowed by use. The scheme of geographical differentiation, intrinsically important and with broad practical implications (differentiation of the venom) is found to be the culmination of a long series of deficient analyses, and in urgent need of proper investigation. Key words: Crotalus durissus, Viperidae, geographical differentidation, differentiation of the venom. INTRODUCTION old literature is confused and confusing: it has been analyzed at several reprises by Klauber (q.v.i.), who The assemblage of forms currently known as the proposed a sensible, if rather uninspired scheme, subspecies of Crotalus durissus embodies some of generally adopted. Geographical differentiation, the most interesting problems in Neotropical her- obvious and intense, was deplorably dealt with by petology. They constitute a set of closely related Hoge (1966), whose cursory work has been accepted parapatric forms, whose mutual relations and mech- in the literature without evaluation, culminating in anisms of speciation, never yet properly studied, the thorough but uncritical compilation by McCranie are conceivably of great theoretical interest. Addi- (1993). tionally, on the practical side, geographical differ- The very extensive range of the group and the entiation has been demonstrated in the chemistry of relatively large size of the individual snakes raise the venom, a fact of far-reaching and urgent med- considerable logistic problems to a comprehensive ical as well as zoological implications. In contra- revision. We have undertaken a piecemeal review distinction with these attractive features, studies on of the Brasilian forms, using mostly the materials the group have been few and undistinguished. The at hand in our institutions and aiming initially at a formal traditional taxonomic treatment, to be fol- Correspondence to: P.E. Vanzolini E-mail: [email protected] lowed, if feasible, by investigations in more depth An. Acad. Bras. Cienc., (2002) 74 (1) 38 PAULO E. VANZOLINI and MYRIAM E.V. CALLEFFO of the evolutionary aspects. Thus the present review seum Regis, to Bradley (1721), and to Seba (1734- of papers of systematic or distributional importance. 1765). Additional notes referred to its venomous- We have organized the matter in four sections: ness, to its eating birds and squirrels on trees, to (i) a history of the systematic concepts in what they its being predated upon by hogs and to the exis- refer to South America; (ii) papers that contain pre- tence of a natural antidote (‘‘senega’’, or milkwort, cise geographic information, listed in Appendix 1; root, a Polygala). All these are well-known parts of and (iii) papers that, although mentioning South North American folklore, early reported in Europe American rattlers, contain no information useful in by Kalm (1752). the present context, so denoted in the References. 2. C. dryinas, 165 + 30 scales, from ‘‘America’’, There is one additional section on chromatism, and with a laconic note on color pattern, and a refer- a concise gazetteer. ence to Amoenitates Academicae 1: 217 (Linnaeus 1749). This is a mistaken reference: the page men- A HISTORY OF CONCEPTS AND NAMES tioned is part of a botanical dissertation on ‘‘Pe- Usually, the review of old literature is evocative and loria’’ . However, in the same Amoenitates, in the pleasant. Not here: the literature on South Ameri- chapter entitled Museum Principis, p. 578, n◦ 24, can Crotalus is very uneven and uncommonly unre- is described an ‘‘Anguis (Crotalophorus) scutis ab- warding. Rattlesnakes are charismatic animals, sur- dominalibus CLXV, caudalibus XXX’’, which is rounded by legend, and from early times attracted certainly C. dryinas. Eight references are made to the attention of travelers of diverse scientific com- the literature. Five are useless to us: Ray (1693), petence, who tended to write copiously on them. Seba (1734-1765), Jonstone (1650-1653), Nierem- These, mostly naive, travel reports constitute the raw berg (1635) and Olearius (1674). Three other ci- materials of practically all the early literature (Cur- tations are potentially useful, to Marcgrave (1648), ran 1935). Specimens, with or without locality data, Piso (1648) and Hernandez (1651) – but in fact they were surprisingly rare in collections, and sparingly are contradictory. The former two would point to reported upon. northeastern Brasil, the latter to Mexico. One juve- Linnaeus (1758: 214) diagnosed the genus nile (‘‘barely 2 feet long’’) was available, gray with Crotalus as snakes having (widened) ventral scales, yellowish dorsal spots; no doubt a faded specimen. small or large (actually divided or undivided) sub- 3. C. durissus, with 172 + 24 scales, was referred to caudals, and a terminal rattle, or crepitaculum. He Kalm (1752, 1753), to Gronovius (1763-1764) and included three species, all three marked with the to the Amoenitates 1: 500. This last citation is again ‘‘Mars sign’’, , that at the time already signified a mistake: the page mentioned (part of the thesis in the general literature ‘‘male’’, but that in the con- Surinamensia Grilliana) contains reference to one text of the Systema Naturae indicated instead that Amphisbaena and to Anilius scytale, not to Crotalus. the species had poison fangs (Linnaeus 1758: 194- Instead, on page 510 of the same Surinamensia Gril- 195). For each species Linnaeus gave scale counts liana there is a ‘‘Crotalophorus scutis abdominalibus (ventrals and subcaudals), country of origin (‘‘habi- CLXXII, scutis caudalibus XXI, paribusque squa- tat’’) and, in two cases, summary notes on color marum III’’, which is certainly C. durissus. Ref- pattern. He also included bibliographic references, erences in the Amoenitates are to Jonstone (1650- to his own pre-Systema work and to contemporary 1653), to Nieremberg (1635), to Olearius (1674) to authors. The species were: vol. 1, part 1, of the ‘‘Museum Imperiale Petropoli- 1. Crotalus horridus, 167 ventrals + 25 subcau- tanus’’ (1742), and toVincent (1726). None of them dals, from ‘‘America’’. References are given to Lin- is of any present use. Additionally, Swedish scien- naeus’s own ‘‘Mus. Ad. Fr.’’, better known as Mu- tists who reviewed surviving Linnean herpetologi- An. Acad. Bras. Cienc., (2002) 74 (1) A TAXONOMIC BIBLIOGRAPHY OF THE SOUTH AMERICAN SNAKES 39 cal types (Lönnberg 1896, Andersson 1900, Holm – three of them, he says, depicted by Seba (1735: 1957) make it clear that no rattlesnake type is extant. pl. 45, fig. 4). (Incidentally this, a precise and reli- able locality, is unusual for a Seba plate). Vosmaer It is evident that Linnaeus recognized three comments on the Linnaen device of characterizing species of rattlesnakes, based on actual specimens, snake species by counts of ventral and subcaudal but that his understanding of these was confused scales, and attempts to identify his own specimens and did not go beyond the generic level. It is a con- by this means. He finds them in agreement with Lin- spicuous fact in the history of the knowledge about naeus’s horridus. This was the beginning of the pre- rattlesnakes that their being large venomous snakes Klauberian tradition of applying horridus to South sporting a rattle did for a long time overshadow more American snakes. This was not such an unreason- systematic information. In the case of the Linnaean able construction, especially given the information names it is impossible to restore the original con- on Seba’s specimens. Klauber’s purely pragmatic cepts. Short of squarely dismissing them (to us the proposal (see below) was in fact motivated by the best alternative, but too late now), the solution is lack of positive data on the Linnaean types and on to find an acceptable