Search

Although species evolve in response to many intrinsic and extrinsic factors, frequently one factor has a dominating influence on a given organ system. In this context, mouthpart shape and function are thought to correlate strongly with dietary niche and this was advocated for decades, e.g. for insects. Orthoptera (grasshoppers, crickets, and allies) are a prominent case in this respect because mandible shape has been even used to predict feeding preferences. Here, we analyzed mandible shape, force transmission efficiency, and their potential correlation with dietary categories in a phylogenetic framework for 153 extant Orthoptera. The mechanical advantage profile was used as a descriptor of gnathal edge shape and bite force transmission efficiency in order to understand how mandible shape is linked to biting efficiency and diet, and how these traits are influenced by phylogeny and allometry. Results show that mandible shape, in fact, is a poor predictor of feeding ecology and phylogenetic history has a strong influence on gnathal edge shape. Being ancestrally phytophagous, Orthoptera evolved in an environment with food sources being always abundant so that selective pressures leading to more specialized mouthpart shapes and force transmission efficiencies were low. [ABSTRACT FROM AUTHOR]

Pre-Pleistocene fossils of Anolis lizards from the mainland of the Americas are exceedingly rare: only two specimens referred to a single species have been described previously. Here we report on a third specimen, preserved (as are the other two) in Miocene amber from Chiapas, Mexico, and consisting primarily of the anterior vertebrae of the caudal sequence. Despite the fragmentary nature of the fossil, it preserves key osteological characters that permit confident referral to the Anolis clade and further suggest placement within the Dactyloa subclade in a clade of three extant species within the Anolis aequatorialis series. The Chiapan provenance of the fossil indicates that the geographic distribution of the Dactyloa clade (and possibly that of the A. aequatorialis series) extended considerably farther north during the Miocene. Although the new fossil represents a different part of the body than the two fossils representing the fossil species Anolis electrum, its inferred phylogenetic relationships are the same as one of the several possible phylogenetic relationships of that species and thus allow for the possibility that all three specimens belong to the same species. [ABSTRACT FROM AUTHOR]

† Kryptovelona carstengroehni gen. et sp. nov. and † Orussus juttagroehnae sp. nov. are the first female members of the parasitoid wasp family Orussidae recorded from Baltic amber. We describe them, including relevant parts of the internal anatomy examined with synchrotron scanning. The fossils display a number of modifications in the antennae and foreleg correlated with the specialized host-detection mechanism, and in the ovipositor apparatus, as well as in the thorax and abdomen for accommodating the internalized ovipositor. The presence of these and other features places them as crown-group members of the Orussidae, as demonstrated by Bayesian phylogenetic analyses. The recently described stem-group orussoid fossils from Burmese amber, the probable female † Cretorussus vilhelmseni , and probable male † Burmorussus mirabilis (both placed in Burmorussidae), were also included in the dataset. By comparing the new Baltic amber taxa with † Cretorussus , it is possible to trace the progressive refinement of the echolocation mechanism through reductions in the number of antennomeres and foreleg tarsomeres. Unfortunately, † Cretorussus does not have the posterior part of the abdomen with the ovipositor preserved. Nevertheless, it is possible to infer that the putative echolocation mechanism for host detection evolved at least 100 Mya, whereas the concealed ovipositor apparatus has not been documented in fossils older than approx. 35 Mya. [ABSTRACT FROM AUTHOR]

Arthroleptidae are an ecologically diverse group of sub-Saharan frogs. Arthroleptid tadpoles predominately occur in slow flowing to torrent waters. Their musculoskeletal system and the relationship between tadpole morphology and lifestyle are poorly understood. Here, we investigated the cranial morphology of four arthroleptid tadpoles occurring in different microhabitats: Leptopelis parkeri , Astylosternus occidentalis , Trichobatrachus robustus , and Nyctibates corrugatus. The crania of the tadpoles of A. occidentalis , N. corrugatus , and T. robustus are highly modified relative to L. parkeri , with wide and partly or completely fused cornua trabeculae, a fused cartilago labialis superior, as well as several modifications of the palatoquadrate, such as a broad commissura quadratocranialis and a processus ventralis which expands the surface for the origin of the large m. orbitohyoideus. The processus hyoquadratis is an evolutionary novelty, forming a functional unit together with the ceratohyale in the cranium of N. corrugatus. Finally, we compared the cranial morphology of these arthroleptids to other lotic and non-lotic species. Although the processus ventralis is not a generalized feature of the cranium in lotic species, it is not present in lentic species. [ABSTRACT FROM AUTHOR]

Controlling the morphology of filamentous fungi is crucial to improve the performance of fungal bioprocesses. Microparticle‐enhanced cultivation (MPEC) increases productivity, most likely by changing the fungal morphology. However, due to a lack of appropriate methods, the exact impact of the added microparticles on the structural development of fungal pellets is mostly unexplored. In this study synchrotron radiation‐based microcomputed tomography and three‐dimensional (3D) image analysis were applied to unveil the detailed 3D incorporation of glass microparticles in nondestructed pellets of Aspergillus niger from MPEC. The developed method enabled the 3D analysis based on 375 pellets from various MPEC experiments. The total and locally resolved volume fractions of glass microparticles and hyphae were quantified for the first time. At increasing microparticle concentrations in the culture medium, pellets with lower hyphal fraction were obtained. However, the total volume of incorporated glass microparticles within the pellets did not necessarily increase. Furthermore, larger microparticles were less effective than smaller ones in reducing pellet density. However, the total volume of incorporated glass was larger for large microparticles. In addition, analysis of MPEC pellets from different times of cultivation indicated that spore agglomeration is decisive for the development of MPEC pellets. The developed 3D morphometric analysis method and the presented results will promote the general understanding and further development of MPEC for industrial application. [ABSTRACT FROM AUTHOR]

Burmese amber preserves a diverse assemblage of Cretaceous arachnids, and among pseudoscorpions (Arachnida: Pseudoscorpiones), ten species in five families have already been named. Here, we describe a new fossil species from Burmese amber in the pseudoscorpion family Hyidae, providing detailed measurements, photographs and 3D-models from synchrotron scanning. Based on morphology, the new fossil, Hya fynni sp. nov. is placed in the genus Hya, and is nearly identical to extant species in the genus, except for the position of trichobothrium est on the pedipalpal chela, thereby indicating extreme morphological stasis in this invertebrate lineage over the last 99 million years. Hya fynni represents the first described fossil species in Hyidae, and the third described Burmese fossil in the superfamily Neobisioidea. It also joins the garypinid, Amblyolpium burmiticum, in representing the oldest fossil records for extant pseudoscorpion genera. Considering proposed divergence dates, the newly described fossil species bolsters a Gondwanan origin for Hyidae, and provides evidence for the "Late Jurassic Rifting" hypothesis for the Burma Terrane, in which this landmass rifted from Gondwana in the Late Jurassic and collided with Eurasia by the Cretaceous/Eocene. Like Hya species today, H. fynni likely inhabited humicolous microhabitats in tropical forests on the Burma Terrane, supporting ecological niche stasis for this family since the Mesozoic. [ABSTRACT FROM AUTHOR]

Pre-Pleistocene fossils of Anolis lizards are rare, although 20 Miocene fossils preserved in amber from the island of Hispaniola have been reported on previously. Using light-microscopy and computed-tomography imaging, we studied a new amber fossil Anolis lizard from Hispaniola. The fossil is likely a juvenile and preserves a largely intact left forelimb, including both scales and skeletal elements, as well as some additional skin, skin impressions, and fragmentary skeletal elements from other parts of the body. Using measurements and lamella counts from the forelimb of the fossil and other juvenile anoles, discriminant function analysis and three Euclidean-distance criteria derived from a principal components analysis consistently support classification of the fossil as a member of the trunk ecomorph category, and those results, in combination with two scale characters preserved in the fossil, suggest that it is a member of the Anolis distichus series within the Ctenonotus clade. These results represent only the third case of a well-supported assignment of an Anolis fossil to the trunk ecomorph category and the first to the A. distichus series. They also highlight that such assignments can sometimes be inferred from highly incomplete fossils. [ABSTRACT FROM AUTHOR]