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Mantellid frogs present an extensive adaptive radiation endemic to Madagascar and Comoros, being the subfamily Mantellinae the most morphologically and ecologically diverse. The Mantellinae present key innovative evolutionary traits linked to their unique reproductive behavior, including the presence of femoral glands and a derived vomeronasal organ. In addition, previous studies pointed to size differentiation in playing an important role in species’ dispersal capacities and shaping of their geographic ranges. Despite the high phenotypic variation observed in this clade, to date an exhaustive morphological analysis of their anatomy has still not been performed, much less in relation to internal structures. Here, we present a comprehensive skeletal description of a mantellid species, Blommersia transmarina, from the island of Mayotte in the Indian Ocean, which has potentially undergone a process of moderate gigantism compared to other Blommersia species. We describe its intraspecific skeletal variation utilizing non-destructive volume renderings from μCT-scans, and characterize the presence of sexual dimorphism and size covariation in skeletal structures. Notably, we found numerous signs of hyperossification, a novel structure for mantellids: the clavicular process, and the presence of several appendicular sesamoids. Our findings suggest that skeletal phenotypic variation in this genus may be linked to biomechanical function for reproduction and locomotion.

In: Contributions to Zoology

The connectivity of groundwater aquifers is lower compared to surface waters. Consequently, groundwater species are expected to have smaller distributional ranges than their surface relatives. Molecular taxonomy, however, unveiled that many species comprise complexes of morphologically cryptic species, with geographically restricted distributional ranges in subterranean as well as in surface waters. Hence, the range sizes of surface and groundwater species might be more similar in size than hitherto thought. We tested this hypothesis by comparing the range size of surface amphipods of the genus Gammarus and subterranean amphipods of the genus Niphargus in Iran. We re-analyzed the taxonomic structure of both genera using two unilocus species delimitation methods applied to a fragment of the COI mitochondrial marker, to identify molecular operational taxonomic units (MOTUs), and assessed the maximum linear extent (MLE) of the ranges of MOTUs from both genera. Genus Gammarus comprised 44–58 MOTUs while genus Niphargus comprised 20–22 MOTUs. The MLEs of the two genera were not significantly different, regardless the delimitation method applied. The results remained unchanged also after exclusion of single site MOTUs. We tentatively conclude that in this case there is no evidence to consider that groundwater species are geographically more restricted than surface species.

In: Contributions to Zoology

The putative monophyly and systematic position of Merodon nigritarsis group was assessed based on morphological and molecular data of the mitochondrial COI and nuclear 28S rRNA genes. The previously reported concept of the group has been redefined, and M. crassifemoris Paramonov, 1925 is now excluded. The related M. avidus group is redefined here, including the Merodon avidus complex and M. femoratus Sack, 1913. Species delimitation of morphologically defined species of M. nigritarsis group was well supported by COI gene analysis, with the exception of M. alagoezicus Paramonov, 1925 and M. lucasi Hurkmans, 1993. Descriptions are given for three new species of the M. nigritarsis species group: Merodon cohurnus Vujić, Likov et Radenković sp. n., Merodon longisetus Vujić, Radenković et Likov sp. n. and Merodon obstipus Vujić, Radenković et Likov sp. n., and one new species from the M. avidus group: Merodon rutitarsis Likov, Vujić et Radenković sp. n. A lectotype is designated for M. femoratus Sack, 1913, and two new synonymies of this species were proposed: M. biarcuatus Curran, 1939 and M. elegans Hurkmans, 1993. Here we review 18 species from the M. nigritarsis group and six species from the M. avidus group and provide morphological diagnoses of the species groups. Additionally, diagnosis of 12 branches (groups or individual taxa) of M. avidus-nigritarsis lineage, an illustrated diagnostic key for the males, and distribution map are provided for the new species.

In: Contributions to Zoology
This book is the first comprehensive work on oriental Notodontidae (Lepidoptera) outside mainland Asia. The studied area includes also Borneo Island, the Malayan Peninsula, entire New Guinea with adjacent islands. All species are illustrated in both sexes with a total number of 1272 specimens on 51 colour plates. Genitalia photos of both sexes as well as detailed distribution maps are provided for each species.
The book deals in the first volume with 298 species and contains descriptions of 99 new notodontid taxa. A second volume will treat with the remaining 160 species and include also a comprehensive biogeographic analysis.
Authors: Un-Hyang Ho and Sam-Rang Song

Abstract

When a widely distributed species undergoes ecological or geological isolation, it tends to divide into subspecies. In general, subspecies differentiation is affected by environmental variance and genetic divergence. But the extent to which these two factors influence subspecies differentiation in species with different distribution ranges and modes of living, might be different. Despite having high breeding habitat fidelity, northern goshawk is a forest raptor that is widely dispersed. We investigated morphological traits in combination with the genetic background of northern goshawk individuals at a large global scale. We also collected genetic, palynological and climatic data to reveal what caused global subspecies differentiation in northern goshawk. Eurasian and North American subspecies populations are thought to have diverged approximately 660 000 years ago to undergo different evolutionary routes, which remarkably facilitated intercontinental subspecies differentiation through genetic lineage divergence. During the last glacial period (18 000 years ago) the different isolation levels of northern goshawk refugia on the continents caused genetic lineage divergences, which, however, are unlikely to have led to subspecies differentiation directly. Spatial environmental variance due to the wide distribution of northern goshawks made an important contribution to subspecies differentiation throughout continents.

In: Animal Biology

Abstract

Many social animals acquire social behaviours during development, and social experience during development can be vital for acquiring necessary social behaviours in adulthood. We investigated the development of a distinctive tactile interaction behaviour in Bronze Cory catfish, in which adults interact with one another tactilely during foraging and during group responses to threats. We found that larvae respond to applied tactile stimulation with a flight response significantly less often as larvae matured. This habituation to tactile stimulation is consistent with developing appropriate adult social behaviour. We also found that social exposure affects the larval response to tactile interactions with conspecifics, and that isolation in early life leads to a greater likelihood of responding to tactile interactions with conspecifics with a flight response. This suggests that social exposure is important for developing social tactile interaction behaviour and underscores the particular importance of early experience in social development.

In: Behaviour

Abstract

Two populations of the European pond turtle were studied employing capture, marking and recapture (CMR) techniques to determine population density and abundance in natural and protected areas within the Regional Natural park Migliarino San Rossore Massaciuccoli in north western Tuscany, Italy. The results indicated strong sexual size dimorphism in both populations, with males smaller than females. In one area Emys orbicularis was in general smaller in size with a very low reproductive rate (three out of 25 adult females were gravid), which contrasted with a second population where 20 out of 42 females were gravid. Population estimates indicated 79 turtles were present in the first area (0.34 ha) and 61 turtles in the second area (0.58 ha), giving an overall density estimate of 183.6 turtles/ha and 146.7 turtles/ha respectively. Whilst our results are similar to those found in other areas of Europe, they diverge from other regions, suggesting that sampling and monitoring techniques should be standardized to obtain comparable data that will enable conservation and protection measures to be recommended.

In: Amphibia-Reptilia

Abstract

We described the reproductive cycle, size-fecundity relationships, reproductive effort, and sexual maturity of Tomodon dorsatus in South Brazil. We examined 87 individuals (25 males and 62 females) from herpetological collections. The description of the reproductive cycle was based on the morpho-anatomical and histological changes in male testes, ductus deferens, and kidney and in female ovary and oviduct. The age at the onset of sexual maturity was estimated by skeletochronology of the caudal vertebra. The reproduction is seasonal semi-synchronous with most of the individuals showing a reproductive peak in the spring. Males and females have developed sperm storage strategies, increasing the reproductive success. Males store sperm in the ductus deferens during the autumn and winter, while females storage takes place in the utero-vaginal junction furrows during the autumn and early winter. Larger females produce a higher number of larger follicles and eggs. Females invest more in growth before reaching sexual maturity than males. Females reach sexual maturity earlier (4 years old) than males (5 years old) and have larger bodies but lower longevity. Reproductive strategies of Tachymenini specie are highly conserved.

In: Amphibia-Reptilia

Abstract

Quantifying and understanding group size distributions can be useful for understanding group behaviour in animal populations. We analysed group size data of the blackbuck, Antilope cervicapra, from six different field sites to estimate the group size distribution of this antelope. We used likelihood based methods (AICs and likelihood ratios) to show that an exponentially truncated power law is the distribution that best describes blackbuck group data, outperforming a simple power-law, an exponential distribution, and a lognormal distribution. Our results show that distribution parameters can be used to draw novel insights regarding group dynamics, and we demonstrate this by investigating how habitat openness affects group size distributions.

In: Behaviour

Abstract

The common wall lizard, Podarcis muralis, is a widely distributed European lizard which has been often introduced across the continent, including north of the continuous species range. Three such populations were recently discovered in the Strzelin Hills in Poland, but no information is available about their origin. We studied the morphological variation, demographic structure and ecology of these populations, as well as their possible origin based on cytochrome b mtDNA sequences. Between 2011 and 2019, the lizards were annually active from the first half of March to mid-October. Males attained significantly larger snout-vent length than females and had relatively larger heads. Almost half of all captured individuals exhibited at least one pileus scale anomaly. Analysis of colour polymorphism revealed the occurrence of three morphs: white, white-red and red. The oldest lizards reached the age of 8 years. These parameters of Polish populations do not deviate from those of other populations from similar latitudes. Molecular analysis revealed that they belong to the most common haplotype of Central European haplogroup I of the Central Balkan clade. This haplotype is widely distributed across the Czech Republic and Slovakia; however, genetic data do not allow determination of the exact origin of the Polish population. Human-mediated introduction from the closest localities, the Czech Republic or Slovakia, is probable but the relict status cannot at present be excluded.

In: Amphibia-Reptilia