A New Triploid Hemidactylus (Gekkonidae: Sauria) from Taiwan, with Comments on Morphological and Karyological Variation in the H. garnotii-vietnamensis Complex

Abstract

The Taiwanese population of the Hemidactylus garnotii-vietnamensis complex is triploid, and is distinct from any known species belonging to this parthenogenetic group (H. garnotii, H. vietnamensis, and presumably H. karenorum). Therefore, we here describe it as a new species, Hemidactylus stejnegeri. This gecko is karyotypically distinct from H. garnotii and H. vietnamensis. In external characters, H. stejnegeri differs statistically from several other local populations of this parthenogenetic species complex. The process of divergence and the problem of taxonomy of the H. garnotii-vietnamensis complex are discussed. lo , ol. 23, No. 1, pp. 50-60, 1989 ciet for the Study of Amphibians and Reptiles i i act lus (Gekkonidae: Sauria) from Taiwan, orphological and Karyological Variation iiiet a ensis Co plex A gekkonid lizard of the parthenogenetic Hemidactylus garnotii-vietnamensis complex was recently recorded from Taiwan (Ota and Hikida, 1985), and shown to differ in several scale characters from the other species assigned to this complex (H. garnotii, H. vietnamensis, and presumably H. karenorum), as well as other unidentified Chinese populations (Ota and Hikida, 1985; Ota et al., 1986). Additional specimens have enabled us to conduct a karyological study upon this gecko, which proves to be triploid and differs from H. garnotii and H. vietnamensis in possessing more biarmed and fewer unirmed chromosomes. Detailed morphological analyses statistically differentiated the Taiwan population from a number of others in H. garnotii-vietnamensis complex. Thus, we here describe this gekkonid lizard as a new species. MATERIALS AND METHODS Fifteen specimens, all females, were collected from Hongye, Hualien Prefecture, Taiwan (Fig. 1), on 11 August 1976, 27 April 1977, and 5 July 1986, by T. Hikida and H. Ota. Of these, five i e a d fe er uni. aile orphological ll i e e tiated the Taiwan e o ot ers in H. gari le . us, e here dei li a as a e species. 50 This content downloaded from 207.46.13.159 on Sun, 23 Oct 2016 05:07:57 UTC All use subject to http://about.jstor.org/terms NEW TRIPLOID HEMIDACTYLUS FIG. 1. Localities of samples used in the present study, including the type locality of Hemidactylus stejnegeri (numbered as 1). Numbers refer to those listed in Table 1. Triangular marking indicates the location of Tahiti, the type locality of H. garnotii. were returned to the laboratory and karyotyped. Animals were intraperitoneally injected with 0.1 ml of colchicine solution (2 mg/ml) per gram body weight, 20 hr before sacrifice. Cells from femur bone marrow were treated with 0.06 M hypotonic KC1 for approximately 30 min, followed by fixation in 1:3 glacial acetic acid: absolute methyl alcohol. Mitotic chromosome preparations were made by an air-dry method and stained in 2% Giemsa solution. The karyotype was determined from 42 well-spread metaphase cells and described using the terminology of Green et al. (1980). We examined all specimens morphologically after preservation in 70% ethanol. Twenty-eight characters (13 meristic and 15 morphometric, as listed in Appendix 1) were counted or measured and used for statistical comparison. Data for Taiwanese specimens were compared with those for other local samples (Table 1). Of these, specimens from Hawaii and Florida were identified as H. garnotii by Kluge and Eckardt (1969), based on karyological data (3n = 70). Four specimens from Vietnam, including two paratypes of H. vietnamensis, were characterized by 3n = 60 (Darevsky et al., 1984). The remaining material was not allocated to species in the absence of karyological data, and because no morphological characters distinguish H. garnotii from H. vietnamensis (Darevsky et al., 1984). We also compared the present species with the descriptions of H. karenorum from southern Asia in Boulenger (1885) and Smith (1935), but no specimens were available for study. Comparisons were made for each meristic charac r by Wilcoxon's 2-sample test. The morphometric characters were analyzed by principal component analysis (PCA) by the PRINCOMP procedure of SAS (1985) using correlation matrix. Differences among sample means in PCA were tested with the ANOVA procedure of SAS (1985). Hemidactylus stejnegeri sp. nov. Fig. 2 Cosymbotus platyurus: Maki, 1923, p. 193. Hemidactylus garnotii-vietnamensis complex: Ota TABLE 1. Specimens of Hemidactylus stejnegeri, and other species and unidentified populations belonging to H. garnotii-vietnamensis complex, used for statistical comparison. Sample number Species Locality N 1 H. stejnegeri Hongye, Taiwan 15 2 H. garnotii Hawaii 10 3 H. vietnamensis Vietnam 4 4 unidentified Fiji 6 5 unidentified New Caledonia 5 6 unidentified Philippines 4 7 H. garnotii Florida 2 8 unidentified Burma 1 9 unidentified India 1 10 unidentified Cook Islands 1 11 unidentified Marquesas Islands 1 12 unidentified Rapa Island 1 51 This content downloaded from 207.46.13.159 on Sun, 23 Oct 2016 05:07:57 UTC All use subject to http://about.jstor.org/terms H. OTA AND T. HIKIDA