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Caecilians of the genus Ichthyophis Fitzinger, 1826 are among the most poorly known amphibian taxa within Southeast Asia. Populations of Ichthyophis from the Indochina region (comprising Cambodia, Laos, and Vietnam) have been assigned to five taxa: Ichthyophis acuminatus, Ichthyophis bannanicus, Ichthyophis kohtaoensis, Ichthyophis laosensis, and Ichthyophis nguyenorum. Barcoding of recently collected specimens indicates that Indochinese congeners form a clade that includes several morphologically and genetically distinct but yet undescribed species. Although body coloration is supported by the molecular analyses as a diagnostic character at species level, unstriped forms are paraphyletic with respect to striped Ichthyophis. Based on our morphological and molecular analyses, three distinct unstriped ichthyophiid species, Ichthyophis cardamomensis sp. nov. from western Cambodia, Ichthyophis catlocensis sp. nov. from southern Vietnam, and Ichthyophis chaloensis sp. nov. from central Vietnam are described as new herein, almost doubling the number of Ichthyophis species known from the Indochinese region. All three new species differ from their unstriped congeners in a combination of morphological and molecular traits. In addition, redescriptions of three unstriped Ichthyophis species ( Ichthyophis acuminatus, I. laosensis, I. youngorum) from Indochina and adjacent Thailand are provided. [ABSTRACT FROM AUTHOR]

Snakes are a very speciose group of squamates that adapted to various habitats and ecological niches. Their ecological diversity is of particular interest and functional demands associated with their various styles of locomotion are expected to result in anatomical specializations. In order to explore the potential adaptation of snakes to their environment we here analyze variation in vertebral structure at the microanatomical level in species with different locomotor adaptations. Vertebrae, being a major element of the snake body, are expected to display adaptations to the physical constraints associated with the different locomotor modes and environments. Our results revealed a rather homogenous vertebral microanatomy in contrast to what has been observed for other squamates and amniotes more generally. We here suggest that the near-absence of microanatomical specializations in snake vertebrae might be correlated to their rather homogeneous overall morphology and reduced range of morphological diversity, as compared to lizards. Thus, snakes appear to retain a generalist inner morphology that allows them to move efficiently in different environments. Only a few ecologically highly specialized taxa appear to display some microanatomical specializations that remain to be studied in greater detail. [ABSTRACT FROM AUTHOR]

The ichneumonid wasp genus Pimpla Fabricius, 1804 is reviewed for the first time from Vietnam. Two new species are described: Pimpla lexuanhuei sp. nov. from Phu Tho Province and Pimpla chuyansinensis sp. nov. from Dak Lak Province. Five further species are recorded as new for Vietnam: P. bilineata (Cameron), P. cameronii Dalla Torre, P. ereba Cameron, P. flavipalpis Cameron, and P. laothoe Cameron. Pimpla instigator (Fabricius, 1793), a junior synonym of P. rufipes (Miller, 1759), previously recorded from Vietnam, was re-identified as P. laothoe and therefore is excluded from the ichneumonid fauna of Vietnam. A key to all ten species listed in this paper is also compiled. [ABSTRACT FROM AUTHOR]

Abstract: The shell of soft-shelled turtles (Cryptodira: Trionychidae) can be characterised by a flexible bridge region, the loss of peripherals and a flattened carapace that is covered not with keratinous shields but with a leathery dermis. Here, we give a detailed description of the bone histology of this natural body armour that is unique not only among turtles but also among all known vertebrates. The flat bone elements have a sandwich-like morphology, with an internal and external compact bone layer framing inner cancellous bone. The external cortex is subdivided into two separate zones. The outer zone of the external cortex, which encompasses the ornamentation pattern typical for trionychid turtle shell bones, is comprised of lamellar bone. Similarly, the whole of the internal cortex is comprised of lamellar bone. The inner zone of the external cortex, however, consists of a highly ordered, plywood-like arrangement of structural collagen fibre bundles within the bone and skin of the shell. The orientation of the collagenous fibres also prescribes the orientation of the mineral phase of the bone, the hydroxyl-apatite crystallites. Strikingly, this peculiar fibre bundle arrangement strongly resembles artificial reinforced fibre-strengthened polymeric materials that combine superior mechanical strength with low weight. We hypothesise that the evolutionary success of soft-shelled turtles is tied to this plywood-like structure of the skin and bone. It may have been the key adaptation that allowed trionychids to greatly reduce and flatten their protective shell, resulting in decreased mineral needs for hard tissues, improved camouflage and hunting performance, biomechanical stability of the shell, as well as overall increased agility and short-term swimming boosts. Significantly, it also may have enabled more efficient cutaneous breathing while still retaining effective armour in both the fossil and Recent trionychid turtles. [Copyright &y& Elsevier]

Abstract: Mesopneumonia of 28 and lungs of 44 species of scincomorph lizards are described, representing mesopneumonia in six of the seven scincomorph families and lungs of all seven families of this taxon. Except for gymnophthalmids and scincids, a family typical organization of mesopneumonia occurs. In cordylids, gerrhosaurids, xantusiids and lacertids the complete right ventral mesopneumonium (VMp) inserts cranially on the posterior vena cava and caudally on the dorsal surface of the right liver lobe. The left VMp is attached to the ventrolateral body wall in cordylids and lacertids; in gerrhosaurids the left VMp is short and inserts on the pericardium and the posterior vena cava; in xantusiids the left VMp is reduced and the lungs are fused cranially with the pericardium. In scincids the VMp of both sides vary in length and insert on the ventral mesentery, or may be lacking completely. The visceral topology of the gymnophthalmids Calyptommatus and Notobachia differs from the general scincomorph pattern, with the liver and stomach elongated and situated on the right and left side of the body cavity, respectively. The left and the right VMp extend over the entire length of the lungs and insert on the ventral mesentery. All lungs examined in the study are single-chambered and show no major structural variability of the inner surfaces, except in lacertids, some gerrhosaurids, Cordylus, and two genera of gymnophthalmids (Echinosaura and Neusticurus). In these groups, rows of dorsomedial niches are present. See also Electronic Supplement at: http://www.senckenberg.de/odes/05-06.htm [Copyright &y& Elsevier]