The two species of rock lizards, Darevsia raddei and D. portschinskii, belong to two different phylogenetic clades of the same genus. They are supposed ancestors for the hybrid parthenogenetic, D. rostombekowi. The present study aims to identify morphological features of these two species and the potential gene introgression between them in the area of sympatry. External morphological features provided

Molecular and morphological methods are used to describe Lernaeodiscus rybakovi, a new rhizocephalan species parasitizing the porcellanid crab Pachycheles stevensii Stimpson, 1858, collected in Russian waters of the Sea of Japan. Molecular analysis of three species, including the new one, confirms the monophyly of the genus Lernaeodicus Müller, 1862 and its recent transfer to the family Peltogastridae

A new species of Capbrya from Brazilian Caatinga is described and illustrated in detail. Capbrya brasiliensis sp. n. is the first record of the genus outside South Africa. We provide the first complete and labelled dorsal chaetotaxy description of the genus including the S-chaetotaxy of tergal segments, and the complete trunk dorsal chaetotaxy of the first instar, described for the first time for the

In a seminal study on elasmobranch systematics, Maisey proposed the monophyly of a large lineage of sharks based primarily on the sharing of an orbitostylic jaw suspension. This group was later redefined as the Squalomorphi, which included Squatinidae but not Batoidea. Subsequent morphological analyses, however, rejected Maisey’s scheme, which was left aside for nearly two decades until the first molecular

Two congeneric species of Japanese field mice, Apodemus speciosus and Apodemus argenteus, differ considerably in their feeding strategies and habitat utilizations. Although both species are omnivorous, previous studies demonstrated that A. argenteus typically eats a wide variety of food items than A. speciosus. Moreover, A. speciosus is a ground dweller, while A. argenteus commonly shows arboreal movements

Based on the unusual characteristics of the male pedipalp and male genital morphology, a new genus and new species of Gagrellinae harvestmen, Thunbergia gretae n. gen. n. sp. (male and female) from Shaanxi Province, China, is proposed. The tibia and tarsus of the pedipalp form elaborate palpal claws, resembling gaspipe pliers, probably used to grasp the legs or the pedipalps of the female during courtship

The Central Ryukyus, a group of islands in southwestern Japan, harbor many endemic reptiles and amphibians, and the geographic ranges of the endemics are limited to south of the Tokara Gap, an old sea strait. Ateuchosaurus pellopleurus is a lizard with an exceptionally wide geographic range that encompasses the Central Ryukyus and north of the Tokara Gap. The intraspecific geographic variation of this

The genus Coenosia Meigen, 1826 (Muscidae: Coenosiinae) is known from all biogeographic regions and is found at high altitudes and in different latitudinal zones. Adults and larvae are predaceous on other insects and some species exhibit sexual dimorphism which can hinder the identification and the association of conspecific specimens. Coenosia inaequalis Malloch, 1934 and Coenosia uniformis Malloch

Species of the genus Mesobiotus are some of the most often recorded eutardigrades throughout the world. The majority of Mesobiotus species have been described based on morphology of the eggs, which is the most important character in this genus, from the taxonomic point of view. In this paper, we analysed in detail the morphology of eggs, oral cavity armature and claws in all known Mesobiotus species

Hoverflies (Syrphidae) represent an insect group of great importance in ecosystems and indicators of ecosystem change. The genus Merodon Meigen, 1803 (tribe Merodontini) is one of the most species-rich hoverfly genera, distributed across the Palaearctic and Afrotropical regions. The genus Merodon Meigen, 1803 is less diverse in the Afrotropical Region than in the Palaearctic (11 versus 160 known species)

Sexual dimorphism in snakes has been mainly evaluated for size and number of some morphological traits, but few studies address on sexual shape dimorphism. Here we evaluated the existence of sexual size and shape dimorphism in the semi-fossorial snake Atractus reticulatus. We use linear and geometric morphometrics to evaluate differences between sexes and among different ontogenetic stages (neonates

The genus Paraba Carbayo et al., 2013 currently includes 16 species of land flatworms, with a distribution restricted to the Brazilian biomes Atlantic Forest and the Cerrado. However, recent ecological studies and inventories carried out in natural areas of southern Brazil and northeastern Argentina indicate the existence of species of the genus that are not yet described. In this study, we describe

Camouflaging with crypsis is a known strategy in several invertebrates such as sea urchins, gastropods, crabs, and immature stage of insects. In harvestmen, soil crypsis are used as a defense strategy. The soil particles are attached to their bodies using secretions. Here we investigate this kind of camouflage in the Malagasy endemic genus Ankaratrix. Members of this genus produce a glue layer (= solidifying

Based on a quantitative mathematical revolution, the study of morphology has had an important emphasis by developing statistical shape analysis. This made possible the combination of multivariate statistical methods and new ways to visualize a morphological structure. Patterns of allometry (shape influence on size) in sexual and non-sexual traits were examined in adults of Cicindelidia trifasciata

The nymphs of three species of Hemiptera: Heteroptera: Dipsocoromorpha, Ceratocombus (Ceratocombus) coleoptratus (Zetterstedt), Ceratocombus (Xylonannus) brevipennis Poppius (Ceratocombidae) and Pachycoleus pusillimus (J. Sahlberg) (Dipsocoridae) are described and illustrated. Keys to species and to nymphal instars are provided. Ontogeny of several morphological features, life cycle, habitats and food

Acanthiophilus and Tephritomyia are medium-sized genera in the family Tephritidae. Both exclusively infest plants of the tribe Cardueae and share several morphological characters. Although both were recently revised based on morphological characters, the phylogenetic relationships between these genera and between them and allied genera in the ‘Tephritis group’ remain unclear because no comprehensive

While the morphology of the adhesive system of geckos has been investigated predominantly in a single species, the tokay Gekko gecko (Linnaeus, 1758), compared to that, there is still the need to examine those traits in a broad diversity of gecko species. Here we focus on the Asian representatives of eublepharid geckos, as a closely related group within Gekkota, and study the anatomy of micro-ornamentation

The larvae of hymenopteran Symphyta are eruciform, with several pairs of abdominal prolegs in addition to three pairs of thoracic legs. However, it is still controversial whether these abdominal prolegs are serially homologous with the thoracic legs. Here we studied the embryonic development of the larval appendages of the large rose sawfly Arge pagana (Panzer, 1798) to investigate the origin and homologous

An interactive, continuously updated identification key to species of the large kinorhynch family Echinoderidae has been made available online. The key is based on the DELTA format (DEscription Language for TAxonomy), and provides, with a multiple entry approach, an intuitive and user friendly tool to identify more than 145 echinoderid species. The present short note describes software requirements

Whip spiders (Amblypygi) are a group of terrestrial arachnids that exhibit fascinating and unique behavioral habits. The genus Heterophrynus has a wide distribution in South America and since most of the species are morphologically (gross morphology) highly similar to each other there is a strong need of revision. To this purpose, we studied the spermatophore morphology, reproductive behavior and the

The Persian squirrel (Sciurus anomalus) is limited to the Irano-Anatolian region of western Asia. The evolutionary history and phylogenetic status of the Persian squirrel are ambiguous. Here, we present a molecular phylogeny using mitochondrial and nuclear genes (D-loop noncoding region, Cyt b, COI, Cmyc, and Rag1) for S. anomalus and other Sciurus species. Our analyses revealed three major clades

Within the Platyhelminthes, Temnocephalida is a clade of continental turbellarians that establish an ectocommensal relationship with their hosts. Many species live associated with decapod crustaceans. In the Neotropical region, two species of Temnocephala are commensals on species of the shrimp family Palaemonidae. Temnocephala digitata lives on Palaemon argentinus and was originally reported from

Spermatozoon morphology, spermatogenesis and reproductive system of Acanthodasys australis (Thaumastodermatidae) were studied at ultrastructural level. The spermatozoon is a filiform cell formed by a cork-screw-shaped acrosome, a helical nuclear–mitochondrial complex and a long flagellum. The acrosome contains an axial tubular structure composed of a pile of electron-dense rings. The helical nucleus

The present study describes the ultrastructural organization of the mature spermatozoon of the lepocreadioid digenean Prodistomum polonii (Lepocreadiidae) by means of transmission electron microscopy (TEM). Live digeneans were collected from the digestive tract of the Atlantic horse mackerel Trachurus trachurus (Teleostei, Carangidae) captured in the coastal zone of the Mediterranean Sea, off La Chebba

Almost all the territory of Poland (except for the Carpathians, Sudetes and Kraków-Częstochowa Upland) was glaciated several times. Nevertheless, based on literature data, over 80 stygobiontic invertebrate species have been found there. Three reasons for such a richness have been hypothesized: survival in refugia situated either in non-glaciated areas or in sub-glacial areas, and re-settling of previously

The hylid tribe Sphaenorhynchini is composed of the single genus Sphaenorhynchus. A recent total evidence phylogenetic analysis of all the 15 currently described species of Sphaenorhynchus recovered S. pauloalvini as the earliest diverging taxon of this genus. Sphaenorhynchus pauloalvini is diagnosed by molecular evidence and several phenotypic characters that differentiate it from the remaining species

The study of the functional anatomy of the female reproductive organs of Brachyura is often used in the classification and establishment of phylogenetic relationships. Besides, it allows us to draw inferences about the reproductive strategies and mating systems of crabs. Using histology and scanning electron microscopy we assessed the reproductive biology of Cyrtograpsus angulatus females by studying:

Platytyphlops sarahae n. sp. is described based on specimens collected in the Mar del Plata submarine canyon and on the slope of the Namuncurá-Burdwood Bank. P. sarahae n. sp. is closely related to the Antarctic species Platytyphlops asperus, from which it can be easily separated by the telson having a central distal seta distinctly shorter than the other two. The presence of a rudimentary squama (exopod)

The genus Minibiotus is morphologically diverse, which may suggest its polyphyletic character. However, scarce genetic data and often also the lack of detailed morphological data currently do not allow for the verification of the relationships within this genus. Here, for the very first time, we provide an integrative description of a new Minibiotus species. Minibiotus ioculator sp. nov. from the Republic