A new Peruvian species of Scybalocanthon Martínez, 1948 (Coleoptera, Scarabaeidae, Scarabaeinae, Deltochilini) and some remarkable intrapopulational variation in the endophallus of S. pinopterus (Kirsch, 1873)

Scybalocanthon asheisp. nov. from Madre de Dios, Peru, is described based on differences in external and male genital morphology. Its diagnostic characters and an updated identification key to the species of the genus are provided as well as new distributional data for the following species: S. acrianus Silva & Valois, 2019, S. aereus (Schmidt, 1922), S. kaestneri (Balthasar, 1939) and S. pinopterus (Kirsch, 1873).

A study on Ptyas doriae (Boulenger, 1888) with comments on the status of Ptyas hamptoni (Boulenger, 1900) (Squamata: Colubridae: Colubrinae)

Ptyas doriae is a rare snake in northeastern India, Myanmar and southern China. The original description and subsequent accounts of this species were all very brief. We studied most of the available specimens of this species and on this basis we provide a detailed redescription of the species. We give an account of intrapopulational variation in scalation characters and colouration and we also report on a previously undescribed colour morph from Manipur, India. We have examined the holotype of Ptyas hamptoni and found that characters used to distinguish it from P. doriae are inadequate and therefore we herein synonymize the former with the latter species. We also predict the potential distribution of P. doriae by using Maximum Entropy modeling.

Comparative Cytogenetics of Omophoita abbreviata and O. aequinoctialis (Coleoptera, Chrysomelidae, Alticini) from the Adolpho Ducke Forest Reserve in Brazilian Amazonia: Intrapopulation Variation in Karyotypes

The chromosomes of 2 flea beetle species from central Amazonia, Omophoita abbreviata and O. aequinoctialis (Alticini), were investigated through analysis of meiotic and mitotic cells. These species belong to the subtribe Oedionychina, a taxon that has unique cytogenetic features, such as giant sex chromosomes which are aligned at a distance during meiosis I (asynaptic). O. abbreviata and O. aequinoctialis have a meiotic formula of 10II + X + y, which is predominant in this subtribe. While the species of the genus Omophoita possess a relatively stable karyotype, a typical feature for Oedionychina, the present study identified inter- and intrapopulational variation in chromosome morphology, constitutive heterochromatin, and the presence and number of B chromosomes in O. aequinoctialis. In addition, FISH mapping of telomeric sequences revealed signals in the collochores, raising several questions on the chromosomal evolution in this group.

Implication of variable characters for the taxonomy of Altiphylax stoliczkai (Steindachner, 1867) and Altiphylax yarkandensis (Anderson, 1872) (Reptilia: Gekkonidae) with comments on the ZSI ‘syntype’ of the latter taxon’

We studied the available specimens of Altiphylax stoliczkai (Steindachner, 1867) collected during the Second Yarkand Expedition (1873–74) by Ferdinand Stoliczka. During our study we found some characters that exhibit intrapopulational variation which were not reported in previously published works on this species. We also examined ZSI 3792, said to be the ZSI syntype of Altiphylax yarkandensis (Anderson, 1872) and provide comments on its taxonomy and true status. Based on our study of specimens of A. stoliczkai and comparison with the published description and photographs of the Natural History Museum (NHM) syntype of A.yarkandensis, we regard the former to be a junior synonym of A. stoliczkai.

Intrapopulational variation in color pattern of Trichomycterus davisi (Haseman, 1911) (Siluriformes: Trichomycteridae) corroborated by morphometrics and molecular analysis

Color patterns of the body are commonly used to distinguish and identify species of Trichomycterus. Therefore, variation in color pattern in a population can cause doubt concerning species identification. With the purpose to test the hypothesis of high variation in color pattern of Trichomycterus davisi (Haseman, 1911), 118 specimens were collected in a stream of a private Ecological Park in southern Brazil, of which 88 were used in the morphological analysis and 30 for DNA barcoding analysis. Three phenotypic classes were determined analyzing the distribution, size and shape of dark brown spots and blotches. The results of morphometric analysis indicate a tendency of association of those pigmentation patterns with the standard length, evidencing ontogenetic variation of color pattern in the species. The results of K2P intraspecific genetic distance (<0.72%), haplotypes network and Bayesian phylogenetic tree corroborate the existence of only one species with a high variable color pattern.

A preliminary study of the taxane chemistry and natural history of the Mexican yew, Taxus globosa Schltdl.

This paper represents a preliminary study of the botany, natural history and taxane chemistry of the Mexican yew, Taxus globosa Schltdl. Taxonomic history, morphological comparison to other North American species and ecological habitat are discussed. Chemical study involved leaf and twig material from forty-nine plants from three localities in Mexico. Levels of taxol, cephalomannine and baccatin III were determined by HPLC analysis. Intrapopulational variation was found to be very high while mean taxane levels for each of the three populations were very similar. The average percentage of taxol in leaves of T. globosa is higher than in all other species of Taxus (0.0121% dry wt.).

Geographic and intrapopulational variation in colour and patterns of an aposematic toad, Melanophryniscus rubriventris (Amphibia, Anura, Bufonidae)

The aposematic toad genus Melanophryniscus is a polymorphic group with noticeable variation in colour and pattern. Here, we objectively evaluate variation in spectral reflectance and quantify variation in patterning within and among populations of the species M. rubriventris in NW Argentina. We conducted spectrophotometric analysis on 69 individuals and recorded dorsal and ventral pattern morphs of 727 individuals from six populations. We found high divergence in the reflectance spectra, the extent of brightly coloured areas, and the skin alkaloid profiles with no correlation among coloration varieties, alkaloid profiles, and the geographic distance between populations. Our analyses imply subdivision of sampled populations groupings based mostly on different dorsal colorations. Our results also reveal that populations with very similar patterns may differ markedly in colour and vice versa. It is striking that these aposematic toads show a pronounced variation in colour and patterning among and within populations showing individuals with a conspicuous bright dorsal colouration but also morphs with a rather cryptic black or drab colouration. However, the known presence of several alkaloids classes in all populations suggests that all morphs might be equally unpalatable.

Morphological variation of Juniperus oxycedrus subsp. macrocarpa (Cupressaceae) in three Italian localities

The intra- and interpopulational geographic variation of three distant populations of <em>J. oxycedrus </em>subsp. <em>macrocarpa </em>was examined biometrically on the basis of morphological key-characters of needles, seeds and cones. The shortest Euclidean distances were used in the agglomerative grouping of closest neighbourhood and discrimination analysis with principal component analysis (PCA) was performed to verify the south-north differentiation of the taxon in Italy. Most of the cone and seed dimensional characters are correlated. No significant correlations were found between cone and needle characters. The sampled populations differ only insignificantly from one another, while the intrapopulational variation is slightly higher. Cone length as well as seed number, width and thickness were significantly correlated with geographic latitude, while the other four characters are not. Differences in cone shape were observed between individuals, so that several morphotypes can be distinguished.