Large Protuberances Research Articles

Recent Southern Hemisphere Lamprimine Stag Beetle in Cretaceous Burmese Amber and Its Biogeographic Implications (Coleoptera: Lucanidae).

A new stag beetle fossil, Prostreptocerus burmiticus Yu & Cai gen. et sp. nov., is described based on a single male specimen. This is the first representative of the subfamily Lampriminae (Coleoptera: Scarabaeoidea: Lucanidae) from mid-Cretaceous Burmese amber. The new species is distinctive among Lucanidae due to its well-developed, right-angled mandible, frons featuring a pair of large protuberances, a coarse and sparsely punctate elytral disc, and large tubercles on the humeri. Prostreptocerus Yu & Cai is placed within Lampriminae based on several key characteristics. Morphologically, it is most similar to the extant Streptocerus Fairmaire, 1850. The current distribution of Streptocerus and Lampriminae is primarily restricted to the Southern Hemisphere, suggesting that this lineage is ancient and existed on Gondwanaland, which has significant geographical implications. This discovery extends the fossil record of Lampriminae and provides additional evidence for the existence of sexual dimorphism and potential combat behavior in Mesozoic lucanids. Additionally, Electraesalopsis Bai, Zhang & Qiu, 2017, previously placed as Lucanidae incertae sedis, shares many characteristics with Prostreptocerus Yu & Cai and is also assigned to Lampriminae based on a suite of traits.

Physical evidence of direct antagonistic interactions between trematodes in the host gut: the kiss of death?

Although within-host competition among parasites if often assumed to occur based on statistical patterns, actual physical evidence of direct antagonistic interactions between parasites, either intraspecific or interspecific, is very rare. Here, we report such evidence between and within two species of hemiurid trematodes infecting the deep-sea grenadier fish Coryphaenoides subserrulatus. We found pairs of worms attached together, with one worm using its ventral sucker against another worm, and sucking out a large protuberance on the victim. We also found single worms showing clear signs of past attacks. There was no evidence that these interactions were more common at high intensities of infection, where the conditions would be expected to be more conducive to competitive interactions. Our findings provide evidence that trematodes may cause some harm to co-occurring individuals, suggesting a direct form of interference competition among intestinal helminths.

Austraplectana extranes sp. n. (Nematoda: Cosmocercoidea) from Australian amphibians Mixophyes carbinensis Mahony, Donnellan, Richards & McDonald (Anura: Myobatrachidae) and Rhinella marina (Linnaeus) (Anura: Bufonidae).

The genus Austraplectana Baker, 1981 is a poorly known group of cosmocercoid nematodes. In the present study, a new species of Austraplectana, A. extranes sp. n., was described using both light and scanning electron microscopy, based on specimens collected from the carbine barred frog Mixophyes carbinensis Mahony, Donnellan, Richards & McDonald (Anura: Myobatrachidae) and the cane toad Rhinella marina (Linnaeus) (Anura: Bufonidae) in Australia. Austraplectana extranes sp. n. can be easily distinguished from its congener by the much longer and different morphology of tails in both sexes, the different number and arrangement of caudal papillae, the presence of single precloacal median heart-shaped papilla and large posterior protuberance with cuticular comb-like fringe in male.

An interesting sexually dimorphic species, Chamobates callipygis Pavlichenko, 1991 (Acari, Oribatida, Chamobatidae), with remarks on sexual dimorphism in Ceratozetoidea.

Based on materials from the leaf litter of a mixed forest in Crimea, a new diagnosis for the sexually dimorphic species, Chamobates callipygis Pavlichenko, 1991, is presented to accommodate its previously unreported females. This is the only species in Chamobatidae showing a distinct sexual dimorphism, which is expressed by the posterior porose region on the notogaster, such that males only have a large protuberance on the posterior part of notogaster bearing a pair of fused porose areas A3, and a densely striated region behind them. The specific function of this structure is not yet known, but the sexual dimorphism is presumably involved in pheromonal communication facilitating sperm transfer. Also, the males of this species have a few transverse striations in the dorsomedial part of notogaster (at level of porose areas A1 and A2). Further, we discuss all cases of sexual dimorphism in the superfamily Ceratozetoidea, and the possible function of this dimorphism.

The cranial base and related internal anatomical features in Homo neanderthalensis and Homo sapiens.

The cranial anatomy of Homo neanderthalensis and Homo sapiens is well documented in the paleoanthropological and medical literature. However, there are few high-quality visual guides of their comparative morphology. We give here a detailed description of the anatomy of two important fossil specimens, La Chapelle-aux-Saints 1 and abri Pataud 1, based on high-resolution imaging data with each specimen representing the respective morphologies of H. neanderthalensis and H. sapiens. We describe the comparative morphology of external, endocranial, and internal characteristics of the cranium, with a focus on the petrous and tympanic portions of the temporal bone. This descriptive approach shows differences between our specimens, including in positions of cerebral components relative to cranial structures and patterns of dural sinus drainage. Numerous external and internal differences in the shape of the petrous temporal are also described, including its articulation with the tympanic bone and the orientation of the petrotympanic crest. The presence of a large protuberance between the osseous Eustachian tube orifice and carotid foramen in H. neanderthalensis suggests that the levator veli palatini muscle took origin more laterally than the dilator tubae arm of the tensor veli palatini muscle, a feature shared with H. sapiens. The overall pattern that emerges is one in which two species have undergone large-scale evolutionary changes in a functionally critical region. Such differences necessitate high-quality visualization and consideration of both internal and external morphology.

Zealandiscus gen. nov., a New Genus Erected in the Family Echiniscidae Thulin, 1928 (Heterotardigrada)

A new heterotardigrade genus, Zealandiscus gen. nov., is erected for the species Echiniscus palmai. Dorsal plates' sculpturing with sparsely distributed large hemispherical protuberances and very tiny granules distinguish this genus from all known members of the genus Echiniscus. The new genus is most similar to the genus Kristenseniscus by the shape of claws and some aspects of dorsal cuticle i.e. presence of sparsely distributed quite large hemispherical protuberances. However, in the newly erected genus dorsal plates' sculpture is “double-like” (i.e. it is composed of two types of granulation visible in different focal planes), hemispherical protuberances are larger and not so dense, dorsal plates are not subdivided into smaller subplates, median plate m3 and ventral subcephalic plates are present. Such autapomorphies fully justify erection of the new genus, even if the genetic data are at present unavailable.

†Laticephalana liuyani gen. et sp. nov., a new bizarre roachoid of †Umenocoleidae (Insecta, Dictyoptera) from mid-Cretaceous Kachin amber

A new genus and species of the extinct beetle-like dictyopteran family †Umenocoleidae, †Laticephalana liuyani gen. et sp. nov., is described based on a well-preserved adult female from mid-Cretaceous Kachin (Myanmar/Burmese) amber. The new genus is characterized by two conspicuous autapomorphies, a triangular posterior extension of the head capsule and four large protuberances of the pronotum. Both structures can be interpreted as mechanic protective devices, but alternative/additional interpretations are possible. The large female subgenital plate is an autapomorphy of Dictyoptera. The transverse pronotal furrow suggests a placement in a clade with †Alienopteridae and Mantodea. A close relationship between †Laticephalana and †Enervipraela is tentatively supported by a very narrow pronotum and relatively short antennae. The very broad head of †Laticephalana with widely separated large compound eyes indicates predaceous habits, and the slender body and well-developed hindwings good flying abilities. The specializations of the distal legs, very similar to the conditions found in †Alienopteridae, suggest a preference for the foliage of trees and shrubs.

Gariwerdichnus warreni igen. et isp. nov. — probable giant myriapod burrows from Late Silurian fluvial channels in the Grampians Group, Western Victoria, Australia

Large Late Silurian burrows are preserved in fluviatile trough cross-bedded sandstones at Mount Bepcha and Mount William in the Grampians in western Victoria (Australia). These burrows have ventral surfaces with two parallel grooves likely formed by the trace-makers’ paired legs as they burrowed through dunes on braided-river beds, probably after avulsion of sandy channels. The burrows are morphologically distinct from previously described burrows and a new ichnogenus Gariwerdichnus igen. nov. containing a single new ichnospecies G. warreni isp. nov. is erected. The size of the burrows, together with their ridged ventral surface, rounded dorsal surface with large dorsolateral protuberances, and meniscate backfill, point towards giant myriapods as the tracemakers. This conclusion is further supported by the presence of large Diplichnites isp. (including D. gouldi) trackways of comparable size in a stratigraphically higher unit at Mount Bepcha; large D. gouldi are typically attributed to giant myriapods. Early myriapod groups that could have formed G. warreni include eoarthropleurids, arthropleurids, or a Bennettarthra-like organism. Chris Gouramanis [ chris.gouramanis@anu.edu.au ], Research School of Earth Sciences, The Australian National University, Australian Capital Territory, 0200, Australia; Anthony, J. Martin [ geoam@emory.edu ], Department of Environmental Sciences, Emory University, Atlanta, Georgia, 30322, USA; John A. Webb [ john.webb@latrobe.edu.au ], Department of Ecology, Environment and Evolution, La Trobe University, Bundoora, Victoria, 3086, Australia.

A new ophthalmosaurid ichthyosaur from the Upper Jurassic (Early Tithonian) Kimmeridge Clay of Dorset, UK, with implications for Late Jurassic ichthyosaur diversity.

A new ophthalmosaurid ichthyosaur, Thalassodraco etchesi gen. et sp. nov., from the Upper Jurassic Kimmeridge Clay Formation of Dorset, UK is described. The specimen, a partial, articulated skull and anterior thorax in the Etches Collection of Kimmeridge, Dorset, is exceptionally well preserved on a slab of laminated coccolith limestone and has been expertly prepared. It comprises a near complete skull in articulation with associated anterior vertebral column and dorsal ribs, complete pectoral girdle, fully exposed left forelimb, and some elements of the right forelimb. Other elements present, including an ischiopubis are preserved on separate slabs. Presumed rapid burial of the anterior portion of the specimen in the coccolith substrate has preserved a number of ossified ligaments lying across the vertebral column and associated ribs as well as stomach contents and decayed internal organs. Aspects of the dentition, skull roof bones and the forelimb configuration distinguishes the new specimen from previously described Late Jurassic ichthyosaurs. Autopmorphies for T. etchesi include a large rounded protuberance on the supratemporal bone; a thin L-shaped lachrymal, with a steeply curved posterior border; ~ 70 teeth on the upper tooth row, and deep anterior dorsal ribs. A well resolved phylogenetic analysis shows T. etchesi as a member of a basal clade within Ophthalmosauridae comprising Nannopterygius, Gengasaurus, Paraophthalmosaurus and Thalassodraco. The new specimen adds to the diversity of the Ichthyopterygia of the Kimmeridge Clay Formation and emphasises the important contribution of amateur collectors in palaeontology.

Spheroidal graphite coalescence during thermal cycling in the ferritic domain of a high-silicon cast iron studied by optical microscopy and X-ray computed tomography

High-silicon cast irons remain ferritic at higher temperature than usual cast irons and present both better oxidation resistance and higher mechanical strength. Such a high-silicon spheroidal graphite cast iron was heat treated up to 50 h in total at 800 °C in two different manners: under isothermal and cyclic conditions. Under the isothermal condition, the distribution of graphite inclusions did not vary significantly. On the contrary, temperature cycling led to spectacular coalescence whose evolution was observed after 1000, 2000 and 3000 cycles. Quite unexpectedly, the largest graphite particles - that were growing because of coalescence - showed an irregular outer surface after 1000 cycles, which evolved in impressive dendritic instabilities and then large protuberances after 2000 and 3000 cycles. Optical microscopy and X-ray computed tomography (XCT) were used to quantitatively study these microstructural changes.

Design and fabrication of PVAc-based inverted core/shell (ICS) structured adhesives for improved water-resistant wood bonding performance: II. Influence of copolymerizing-grafting sequential reaction

PVAc-based inverted core/shell (ICS) structured latex adhesive with improved water- and heat-resistance was prepared by a copolymerizing-grafting sequential reaction approach. The sequential reaction process combines the function of a copolymer layer and an active grafting site to controllably achieve the thermodynamic non-equilibrium ICS morphology with hydrophilic poly(vinyl acetate) (PVAc) cores and hydrophobic polystyrene (PS) shells. The difference between the sequential reaction approach and the chemical grafting method was explored. Structured latex particle morphology, transferring from strawberry-like particles, over particles with large and irregular PS protuberances, to nearly spherical particles with a smooth surface, was microscopically visualized by changing the amount of butyl acrylate (BA) in the PVAc copolymer cores. The heat- and water-resistant bonding of PVAc-based adhesives on wood blocks were evaluated by shear strength at both dry and wet conditions, as well as the boiling water failure time. The results showed that a significant improvement of water- and heat-resistance, especially for boiling water resistance, was successfully obtained. This novel approach paves a way for controlled design and manufacture of high-performance emulsion adhesives through tailoring particle morphology.

Nanopatterned protein-polysaccharide thin films by humidity regulated phase separation

Greater sustainability in mass manufacturing is essential to alleviating anthropogenic climate change. High surface-area, micro- and nano-patterned films have become a fundamental tool in materials science, however these technologies are subject to a dwindling petrochemical supply, increasing costs and disposability concerns. This paper describes the production of patterned biopolymer films utilizing controlled phase separation of biopolymeric thin films into nanopatterns using easily transferable variables and methods. Similar morphologies to those commonly observed with synthetic block-copolymers (BCPs) were achieved across a large range of feature sizes, from 160 nm to >5 μm: Bicontinuous, porous, droplet-matrix, particulated and dimpled. Protein and polysaccharide type, protein to polysaccharide ratio, casting method and ambient humidity were primary conditions found to influence the pore morphology of the films. High protein concentrations (4:1 and 2:1 blends) generally resulted in porous structures whereas high polysaccharide concentrations (1:2 and 1:4 blends) resulted in spherical structures. High humidity conditions (60% + relative humidity) resulted in the growth of large protuberances up to 10 µm in diameter while lower humidity (10–30%) resulted in discrete features smaller than 200 nm.

Laccase production and pellet morphology of Coprinopsis cinerea transformants in liquid shake flask cultures.

Laccase production and pellet formation of transformants of Coprinopsis cinerea strain FA2222 of C. cinerea laccase gene lcc1 subcloned behind the gpdII-promoter from Agaricus bisporus were compared with a control transformant carrying no extra laccase gene. At the optimum growth temperature of 37°C, maximal laccase yields of 2.9U/ml were obtained by the best lcc1 transformant pYSK7-26 in liquid shake flask cultures. Reduction in temperature to 25°C increased laccase yields up to 9.2U/ml. The control transformant had no laccase activities at 37°C but native activity at 25°C (3.5U/ml). Changing the temperature had severe effects on the morphology of the mycelial pellets formed during cultivation, but links of distinct pellet morphologies to native or recombinant laccase production could not be established. Automated image analysis was used to characterise pellet formation and morphological parameters (pellet area, diameter, convexity and mycelial structure). Cross sections of selected pellets showed that they differentiated in an outer rind and an inner medulla of loosened hyphae. Pellets at 25°C had a small and dense outer zone and adopted with time a smooth surface. Pellets at 37°C had a broader outer zone and a fringy surface due to generation of more and larger protuberances in the rind that when released can serve for production of further pellets.

Experimental investigation of the shock-induced flow over a wall-mounted cylinder

The unsteady aerodynamic and aerothermal phenomena resulting from the interaction between a shock-induced supersonic boundary-layer flow and a wall-mounted cylinder are investigated. Experiments were conducted in a shock tube at three different post-shock unit Reynolds numbers and a single Mach number to investigate the effects of differing ratios of inviscid and viscous temporal scales on the flow development. Two cylinder heights were studied: ‘large’ and ‘small’ protuberances based on calculated boundary-layer thicknesses. Heat-flux measurements on the shock-tube wall were performed using an ultra-fast-response temperature sensitive paint and verified by independent thermocouple measurements. High-speed schlieren provided visualizations of the inviscid flow phenomena. The unsteady shock-wave/boundary-layer interaction ahead of the cylinder resulted in high transient heat loading on the wall and caused transition to turbulence of the incoming laminar boundary layer. Once this incoming boundary layer had naturally transitioned, the region of enhanced heat flux collapsed back towards the cylinder; during this process, heat transfer in the immediate wake increased significantly. The overall heat flux upstream of the cylinder was higher for the large protuberance, whereas the downstream heat flux was generally higher for the small protuberance. In the case of the large protuberance, the viscous scaling appeared to best collapse the upstream heat-flux development for the three different unit Reynolds numbers, though the agreement downstream was less satisfactory. Neither the viscous nor the inviscid scaling appeared to adequately collapse the development for the small protuberance.

Molecular phylogeny and morphology of Ophiocordyceps unituberculata sp. nov. (Ophiocordycipitaceae), a pathogen of caterpillars (Noctuidae, Lepidoptera) from Yunnan, China

Ophiocordyceps unituberculata, a new insect pathogenic fungus from southwestern China, is described using molecular phylogenetic and morphological data. This fungus differs from other Ophiocordyceps species by its enormously long monophialidic conidiogenous cells and a large periclinal protuberance often growing near the apex of conidiogenous cells, single conidia (lanceolate to fusiform) embedded in mucous sheath, and much larger conidial dimensions. Four-locus (nrSSU, nrLSU, tef-1α and rpb1) and ITS data phylogenetic analyses show that O. unituberculata belongs to the Hirsutella nodulosa clade within the genus Ophiocordyceps of Ophiocordycipitaceae and is a separate clade from other allied species. Molecular phylogeny and morphology both strongly support the distinctiveness of this taxon. The interspecific relationships in the H. nodulosa clade are discussed.

Morphology and molecular phylogeny of Paragorgia rubra sp. nov. (Cnidaria: Octocorallia), a new bubblegum coral species from a seamount in the tropical Western Pacific

A new species of bubblegum coral, Paragorgia rubra sp. nov., discovered from a seamount at a water depth of 373 m near the Yap Trench is studied using morphological and molecular approaches. Paragorgia rubra sp. nov. is the fourth species of the genus found in the tropical Western Pacific. The new gorgonian is red-colored, uniplanar, and measures approximately 530 mm high and 440 mm wide, with autozooids distributed only on one side of the colony. Paragorgia rubra sp. nov. is most similar to P. kaupeka Sanchez, 2005, but differs distinctly in the polyp ovals with large and compound protuberances (vs. small and simple conical protuberances) and the medullar spindles possessing simple conical protuberances (vs. compound protuberances). Moreover, P. rubra sp. nov. differs from P. kaupeka in the smaller length/width ratio of surface radiates (1.53 vs. 1.75). The genetic distance of the mtMutS gene between P. rubra sp. nov. and P. kaupeka is 0.66%, while the intraspecific distances within Paragorgia Milne-Edwards & Haime, 1857 except the species P. regalis complex are no more than 0.5%, further supporting the establishment of the new species. Furthermore, the ITS2 secondary structure of P. rubra sp. nov. is also different from those of congeners. Phylogenetic analyses indicate Paragorgia rubra sp. nov. and P. kaupeka form a clade, which branched early within Paragorgia and diversified approximately 15 Mya.

Comparative morphology of the distal segments of Malpighian tubules in cicadas and spittlebugs, with reference to their functions and evolutionary indications to Cicadomorpha (Hemiptera: Auchenorrhyncha)

Morphology of Malpighian tubules from fourteen representatives in Cicadoidea and Cercopoidea are investigated. Among which the distal segments that perform a modified glandular function during nymphal stages are investigated in particular using both scanning and transmission electron microscopies. The examined species show regional differentiation along the Malpighian tubules. The terminal parts end as separate rods in Cercopoidea, whereas they are united in pairs and enveloped by a peritoneal sheath shortly before reaching the rectum in Cicadoidea. Ultra-morphologically, the distal segments in Cercopoidea consist of numerous large protuberances containing a few small nodules, and the distal segments in Cicadinae of Cicadoidea comprise numerous large protuberances containing several small nodules. Species of subfamilies Cicadettinae (except Karenia caelatata) and Tettigadinae have undulated distal segments devoid of any protuberances and nodules. The Malpighian tubules of the Karenia cicadas, remarkably without timbals and with questionable systematic placement, morphologically resemble the Cicadinae more than the Cicadettinae (=Tibicininae auct.), indicating it is more reasonable to place this genus into Cicadinae instead of Cicadettinae. Ultrastructurally, numerous secretory granules, secretory vacuoles and rough endoplasmic reticula exist in the distal segments of nymphal spittlebugs, and abundant secretory vacuoles exist in the same region of nymphal cicadas. The secretory structures can secrete productions which may help to create favorable watery conditions for nymphal spittlebugs and cicadas (e.g., inhibiting the growth of certain soil fungi, buffering the pH conditions, and neutralizing the toxic ammonia). In contrast, the distal segments of adult spittlebugs and cicadas are devoid of secretory granules and secretory vacuoles. This suggests that nymphal Malpighian tubules in both cicadas and spittlebugs function to secondary secretion, and become mere excretive organs in adult stage. Analysis of the morphology, layout, and ultrastructure of the Malpighian tubules in Cicadomorpha support the major relationships within this infraorder as “Membracoidea+(Cicadoidea+Cercopoidea)”.

Ossification of the Posterior Petroclinoid Dural Fold: A Cadaveric Study with Neurosurgical Significance.

Objectives The roof of the porus trigeminus, composed of the posterior petroclinoid dural fold, is an important landmark to the skull base surgeon. Ossification of the posterior petroclinoid dural fold is an anatomical variation rarely mentioned in the literature. Such ossification results in the trigeminal nerve traversing a bony foramen as it enters Meckel cave. The authors performed this study to better elucidate this anatomical variation. Design Fifteen adult cadaveric head halves were subjected to dissection of the middle cranial fossa. Microdissection techniques were used to examine the posterior petroclinoid dural folds. Skull base osteology was also studied in 71 dry human skulls with attention paid to the attachment point of the posterior petroclinoid dural folds at the trigeminal protuberances. Setting Cadaver laboratory Main Outcome Measures Measurements were made using a microcaliper. Digital images were made of the dissections. Results Completely ossified posterior petroclinoid folds were present in 20% of the specimens. Of the 142 dry skull sides examined, 9% had large trigeminal protuberances. Conclusions Based on this study, the posterior petroclinoid dural fold may completely ossify in adults that may lead to narrowing of the porus trigeminus and potential compression of the trigeminal nerve at the entrance to Meckel cave.

Sexing Monomorphic Western Mountain Greenbuls on Mount Cameroon using Morphometric Measurements

The western mountain greenbul, Andropadus tephrolaemus, is a poorly-known monomorphic forest greenbul. We investigated whether morphological measurements could be used to discriminate between sexes of this species, with a sample of birds captured in two forest types on Mt Cameroon. We used discriminant function analysis based on a combination of traits to develop models to discriminate between sexes. The sex of birds predicted from these models was compared with molecular sexing of the same individuals. Discriminant analysis revealed that a discriminant function incorporating wing length, tail length and bill height allowed 74% of western mountain greenbuls to be sexed correctly based on morphometric measurements alone. Sex ratios varied between montane and lowland forests, with the former having a higher proportion of males (70.5 and 54.6%, respectively), but the difference was not statistically significant. Cloacal sizes did not differ between males and females, and males do not develop large cloacal protuberances while breeding. This is in agreement with low predicted levels of sperm competition in this species. We show that sexing based on morphology has its limitations, but can still provide some insight if DNA analysis is not available.

A potential contribution of achene micromorphology and phytolith analysis in describing the systematics of genus Bolboschoenus from India

Three entities of taxonomically difficult genus Bolboschoenus collected from India were subjected to micromorphological and phytolith studies. For micromorphological study, silica bodies in the outer cells of the achene epidermis were revealed by acetolysis and sonication and examined by scanning electron microscopy. A silica body consists of a basal platform, one or more large elevated protuberances, and sometimes smaller satellite protuberances. Significant differences have been found in the number of protuberances, the presence/absence of satellites, the texture of the platform, and the occurrence of nodules on the larger protuberances at individual species level. These features, combined with achene shape and characteristics of the anticlinal walls of the epidermal cells (undulate vs. straight, thick vs. thin, buttressed or not), are expressed in a unique combination for each entity. It is clearly evident from the study that micromorphological characters of the achene epidermis vary significantly between different species. Therefore, the micromorphology of the achene epidermis of Bolboschoenus is valuable in understanding the taxonomy at infraspecific, specific and supraspecific levels in the genus. Results provided by phytolith analysis are useful not only in taxonomic demarcation of Bolboschoenus, but they will be useful in future archaeobotanical and paleoecological investigations also. In conclusion, present study confirms the presence of B. affinis and B. glaucus in India, while suggests more investigation on presence of B. maritimus in India.