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Bijdragen tot de Dierkunde, 63 (1) 3-14 (1993) SPB Academie Publishing bv, The Hague Morphological characterization, cytogenetic analysis, and geographical distribution of Marbled Newt Triturus the Pygmy marmoratus pygmaeus (Wolterstorff, 1905) (Caudata: Salamandridae) M. García-París P. Herrero C. Martín J. Dorda M. Esteban & B. Arano Museo Nacional de Ciencias Naturales, José Gutiérrez Abascal 2, E-28006 Madrid, Spain Keywords: Taxonomy, cytogenetics, Salamandridae, Triturus, Iberian Peninsula T. m. mar- T. Abstract moratus o a m. pygmaeus. Estos rasgos se aplican a series de individuos procedentes de colecciones científicas o bien observa- dos directamente sobre el terreno. Como consecuencia de la Triturus marmoratuspygmaeus, a problematicsubspecies of the aplicación de estos criterios, el área de distribución de T. m. pyg- Marbled Newt from the southern part of the Iberian Peninsula, maeus se extiende considerablemente hacia el norte. La distribu- is redescribed using specimens collected in the “typical” area. la ción de T. m. marmoratus incluye mitad septentrional de la external features Diagnostic morphological are provided to per- Península Ibérica y la mayor parte de Francia, mientras que T. mit the accurate determination ofthe specimens belonging either m. pygmaeus ocupa unaampliaporción en la región sudocciden- T. T. These to m. marmoratus or to m. pygmaeus. diagnostic tal de la Península Ibérica. La zona de contacto entre ambas features were applied to individuals both from the field and subespecies parece localizarse a lo largo del Sistema Central en from museum collections. The results indicate a larger distribu- Portugal y España. T. m. marmoratus sobrepasa hacia el sur el tional area for T. m. pygmaeus than was previously recognized. Sistema Central en tres áreas: Serra da Estrela (Portugal), Sierra The distribution of T. m. marmoratus ranges over the northern de Gata Sierra de Guadarrama El único (España) y (España). half of the Iberian Peninsula and most of France; T. m. pyg- punto en el que T. m. pygmaeus sobrepasa hacia el norte estas maeusoccupies the southwestern part of the Iberian Peninsula. montañas, se sitúa en las proximidades del Puerto de Malagón The contact areabetween the two subspecies seemsto be located (Madrid, España). No se han observado casos de simpatría es- alongthe Central Range Mountains (Sistema Central) in Portu- ni individuos tricta, con rasgos intermedios entre ambas gal and Spain. T. m. marmoratus extends southwards beyond subespecies. Los resultados de un extenso análisis citogenético this borderline in three areas: Serra da Estrela (Portugal), Sierra no muestran la existencia de diferencias entre T. m. marmoratus de Gata (Spain) and Sierra de Guadarrama (Spain). The only T. si bien y m. pygmaeus, la población de T. m. pygmaeus de point at which T. m. pygmaeus reaches northwards beyond the Doñana (Huelva, España) muestra un patrón particular, aunque Central System is near Puerto de Malagón (Madrid Province, de bandas poco diferenciado, C. of strict individuals Spain). No cases sympatry, nor with inter- mediate morphologicalfeatures have been observed. The results of an extensive cytogenetical analysis do not show any dif- Introduction ferences between T. m. pygmaeus and T. m. marmoratus. In- the T. from terestingly, however, m. pygmaeus populations Doñana (Huelva Province, Spain) showed an exclusive, though The marbled newt Triturus marmoratus (Latreille, little differentiated, C-banding pattern. 1800), occurs over a large part of western Europe, from northwestern and central France in the north to southern Portugal and southwestern Spain in Resumen the south. Most authors accept the existence of two subspecies, T. m. marmoratus, widely spread redescribe Se Triturus marmoratus pygmaeus, Una subespecie over most of the area described, and T. m. pyg- problemática de triton jaspeado del sur de la Península Ibérica, maeus (Wolterstorff, 1905), which is limited to the utilizando para ello especímenes procedentes de su área “típi- southern part of the Iberian Peninsula (Macgregor ca”. Se definen caracteres morfológicos externos que permiten la identificación de los individuos pertenecientes a et al., 1990). Downloaded from Brill.com09/23/2021 11:57:05AM via free access M. Gara'a-Paris et al. Triturus marmoratus 4 pygmaeus Table I. External of of T. from Cantabria and T. from Cádiz measurements (in mm) specimens m. marmoratus m. pygmaeus (Spain). are: = = = Variables measured TL = total length; SV snout-vent length; FHL distance between forelimbs and hindlimbs; FLL fore- HLL = 3HF HW HL limb length; 3FF = third finger length; hindlimb length; = third toe length; = head width; = head length. TL SV FHL FLL 3 FF HLL 3HF HW HL T. m. marmoratus Males mean 132.1 72.9 37.5 29.3 8.8 28.5 9.5 12.8 15.6 n = 20 SD 9.04 6.16 2.90 2.56 1.2 2.86 1.0 1.20 1.72 Females mean 148.4 81.5 47.2 29.7 7.9 29.2 8.0 14.3 17.9 n = 15 SD 10.45 5.47 3.69 2.82 0.9 1.83 0.7 1.22 1.48 T. m. pygmaeus Males mean 106.5 59.4 28.9 21.6 6.5 11.7 7.2 10.7 15.1 n = 15 SD 9.02 5.35 4.45 1.63 0.8 1.77 0.7 1.21 1.42 Females mean 116.5 61.1 33.7 21.0 5.8 20.9 6.0 11.8 15.9 n = 10 SD 5.01 3.17 2.15 1.28 0.8 1.35 0.4 0.85 1.58 The most recent studies on the morphology, im- Material and methods munology, and genetics of T. marmoratus and allied species (Dorda & Esteban, 1986; Busack et Twenty-five specimens, collected during their aquatic phase in San and Los Barrios Cádiz al., 1988; Macgregor et al., 1990) point to the com- Roque (Algeciras Bay, Province, used for the of Spain), were redescription T. m. pygmaeus. plexity of the group and suggest that a revision of These capture sites were selected by consideration of two facts: the taxonomie status of T. m. pygmaeus may be ap- firstly, the "terra typicarestricta" for T. m. pygmaeus as report- propriate. ed by Mertens & Miiller (1928) is Cádiz, and within the Cádiz One of the is the in problems difficulty correctly Province, Algeciras is one of the two sites mentioned by Wolterstorff the external features of the in- identifying individuals belonging to each subspe- (1905). Secondly, dividuals from these populations are similar to those indicated cies. This seems partly due to the lack of reliable by Wolterstorff in the original description. diagnostic features, as well as to an extended mis- Thirty-five T. m. marmoratus individuals from different sites interpretation of Wolterstorff's abbreviated (1905) in Cantabria (northern Spain) were used as specimens for com- of m. description T. pygmaeus. This misinterpreta- parison in order to establish the diagnosticfeatures of T. m. pyg- Some individuals of tion arises from the confusion of the extremely maeus. both groups were kept alive until the end ofthe breedingperiod in order to describe their colouration small size of specimens of the coastal populations during the terrestrial phase. Measurements and description of from southwestern Spain with that of the small external features and colouration were all made on live speci- individuals originally described Wolterstorff by mens. External measurements are indicated in Table I. Statisti- (1905). cal analysis is restricted here to the use ofthe /-test for compari- son of mean values (Zar, 1984). Once the diagnostic features were established, we proceeded In the present study the southern subspecies to revise the material available from some museum collections is (T. m. pygmaeus) redescribed using specimens and to conduct a field inspection of selected populations(cf. Ap- from the "typical" area. Some diagnostic morpho- pendix). After the subspecific assignation, 255 specimens from logical and features of T. cytogenetic m. pygmaeus diverse localities were measured preserved or alive. A two-group T. are proposed that allow its correct identification. comparison of the resultant T. m. marmoratus and m. pyg- conducted discriminant anal- The maeus samples was using stepwise diagnostic features are applied to individuals from the Discriminant ofBMDP ysis program package (Dixon, collected in the field and from museum collec- 1975). Total length was excluded from this analysis. tions and the resultant distributional limits are in- For use in cytogenetic analysis, 80 males and 73 females from dicated. 22 localities were injected with 0.05 ml of a Downloaded from Brill.com09/23/2021 11:57:05AM via free access Bijdragen tot de Dierkunde, 63 (I) - 1993 5 solution of 24 h before that of with an 0.1% colchicine per gram body weight, a light yellowish background orange they were sacrified. Testes and intestine were removed and hue which several and white on large blackish spots placed in 0.05 M KC1 for 5 minutes, subsequently fixed in a solu- dots may be found. These white dots usually show 48 tion of ethanol and acetic acid (3:1) for a minimum of h, and the flanks and a higher density on occasionally then stored in 70% ethanol at 4°C. Preparations of mitotic chro- the colouration. and cover background mosomes were made using the squash technique were air completely White dots also the base of the dried after immersion in liquid nitrogen. The slides were are present on C-banding method described by Sumner neck the processed followingthe flanks, spreading over the sides of the and (1972) with slight modification: incubation time in freshly satu- cheeks, here alternating with black spots. The ven- at rated Ba(OH) solution was 5 min. 60°C. They were then 2 tral dark and roundish in spots are usually large rinsed in 1% acetic acid solution for 5 min. The slides obtained males and small and more elliptically shaped in fe- were incubated in 2 x SSC at 60°C for 30 min.