Psammosteiforms (Agnatha,Heterostraci) from the Lower Frasnian of the Mikhailovskii Mine,Kursk Region,Russia

Psammosteiforms, including Tartuosteus (?) zheleznogorskensis, sp. nov. and Psammosteus cf. P. praecursor Obruchev, from the Lower Frasnian (Upper Devonian) of the Mikhailovskii Mine (Kursk Region) are described. Agnathans, placoderms, crossopterygians, and acanthodians from this locality are determined. The similarity of the Mikhailovskii Fish Assemblage to the assemblage of southern Timan suggests it be assigned to the Upper Timan Regional Stage.     

Origins of bone repair in the armour of fossil fish: response to a deep wound by cells depositing dentine instead of dermal bone

The outer armour of fossil jawless fishes (Heterostraci) is, predominantly, a bone with a superficial ornament of dentine tubercles surrounded by pores leading to flask-shaped crypts (ampullae). However, despite the extensive bone present in these early dermal skeletons, damage was repaired almost exclusively with dentine. Consolidation of bone, by dentine invading and filling the vascular spaces, was previously recognized in Psammolepis and other heterostracans but was associated with ageing and dermal shield wear (reparative). Here, we describe wound repair by deposition of dentine directly onto a bony scaffold of fragmented bone. An extensive wound response occurred from massive deposition of dentine (reactionary), traced from tubercle pulp cavities and surrounding ampullae. These structures may provide the cells to make reparative and reactionary dentine, as in mammalian teeth today in response to stimuli (functional wear or damage). We suggest in Psammolepis, repair involved mobilization of these cells in response to a local stimulatory mechanism, for example, predator damage. By comparison, almost no new bone is detected in repair of the Psammolepis shield. Dentine infilling bone vascular tissue spaces of both abraded dentine and wounded bone suggests that recruitment of this process has been evolutionarily conserved over 380 Myr and precedes osteogenic skeletal repair.     

云南文山大窗鱼(Macrothyraspis)属一新种

记述了产于云南文山古木早泥盆世坡松冲组华南鱼类大窗鱼一新种——长矛大窗鱼(Macrothyraspis longilanceus sp.nov.)。新种头甲呈头盔形,吻突与角均很发育,中背孔呈后缘前凹的桃形,头甲背面具一对蚕豆形的背窗,纹饰为细小的粒状瘤点,这些特征与属型种——长角大窗鱼(Macrothyraspis longicornis)相似。但新种吻突特别长,约为头甲中长的2 倍,眶孔背位,两个背窗之间脑腔和迷走腔区域相对较宽,两个侧向延伸的角向后倾斜,末端不前翘等,与属型种区别明显,应为该属的一新种。     

Description d'une nouvelle espèce et analyse morpho-fonctionnelle du genre Doryaspis White (Heterostraci) du Dévonien du Spitsberg

Doryaspis groenhorgensis nov. sp. is a new pteraspidiform from the lower devonian of Spitsbergen. The genus Doryaspis is now considered as the most abundant pteraspidiform of the Wood Bay formation, with five described species. Moreover, the pteraspidiform diversity of this formation has been under rated all along the XXth century. A morpho-functional analysis of the Doryaspis generic characters (e.g. flat dorsal shield, ventral pseudorostrum, long cornual plates) allows to consider two possible mode of life. However, none of the pelagic or benthic mode of life is better supported than the other. The same analysis introduce some interpretative hypothesis on histology and moving of the Pteraspidiformes. The Pteraspidiformes diversity of Spitsbergen is important for further Devonian circum-arctic comparisons (e.g. siberian platform).     

滇东南早泥盆世无颌类

文中记述了华南鱼类两个新属,即 Gantarostrataspis gengi gen. et sp. nov. 和 Gumuaspis rostrata gen. et sp. nov.,同时对含鱼层的时代进行了讨论.     

The first juvenile specimen of Eolacerta (Squamata: Eolacertidae) from the early–middle Eocene of the Messel Pit (Germany)

We describe the first juvenile specimen of an eolacertid lizard. The material comes from one of the most important Eocene localities, the Messel Pit in Germany. The new specimen provides unique information on the early ontogeny of Eolacerta, the largest known lizard from Messel, with a maximum snout-vent length greater than 30 cm and a mass approaching 1 kg. The specimen described here, with a SVL of 11.3 cm and an estimated mass of 21 g, can be allocated more precisely to Eolacerta robusta based on the co-occurrence and the combination of following features: (1) the nasal process of premaxilla is long; (2) position of lacrimal (being more anteriorly located in Stefanikia siderea); (3) the postorbital process of jugal is broad; (4) the ratio of the anterior and posterior region of the frontal between the sulcus interfacialis; (5) a mid-parietal constriction of the parietal table is present; (6) the interparietal shield broadens anteriorly; (7) the transverse sulcus is straight anteriorly. The incipient character of the parietal constriction and the slightly lower number of maxillary teeth (28 vs. 30–32 in adults) are consistent with a juvenile animal. Very important is evidence for the presence of pterygoid dentition (pointed teeth arranged in a single line) and the absence of palatine dentition. Ceratobranchial I is observed for the first time for this species, and its shape and length are very similar to those of Lacertidae. There are 27 presacral vertebrae in the juvenile, as in adults. In the juvenile specimen, ventral keel on the centrum is present in all vertebrae. The ventromedial portion of the ischium is well preserved here and gives information on the exact shape of this portion, at least in juvenile form. The scalation, as far as it is preserved, is similar to that of Stefanikia, except that the rectangular subdigital scales are longer in comparison with their width, and therefore have a broader appearance.     

Properties of an α-1,3-Glucanase from Streptomyces sp. KI-8

Srome properties were examined of purified α-l,3-glucanase isolated from the culture supernatant of the soil microorganism Streptomyces KI-8.

The optimum pH and temperature were pH 5.4 and 60°C, respectively. The α-1,3-glucanase was stable up to 50°C on heating for 10 min. This enzyme hydrolyzed the substrate α-l,3-glucan into glucose and nigerose by an endo-type of action. Nigerotriose, nigerotetraose and nigeropentaose were hydrolyzed into glucose and nigerose, whereas nigerose was not attacked. The degree of hydrolysis of pseudonigeran, Lentinus α-1,3-glucan, mutan IG-1 (less soluble fraction) and IG-2 (more soluble fraction) by the α-1,3-glucanase were 28.5%, 14.3%, 8.8% and 10.0%, respectively. Km values (mg/ml) for pseudonigeran, Lentinus α-l,3-glucan, mutan IG-1 and IG-2 were 1.12, 1.98, 8.00 and 5.00. The enzyme solubilized 50 to 80% of mutan by concerted action with dextranase.     

Somatic embryogenesis and regeneration of Cenchrus ciliaris genotypes from immature inflorescence explants

An efficient, highly reproducible system for plant regeneration via somatic embryogenesis was developed for Cenchrus ciliaris genotypes IG-3108 and IG-74. Explants such as seeds, shoot tip segments and immature inflorescences were cultured on Murashige and Skoog (MS) medium supplemented with 2.0–5.0 mg dm^?3 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.5 mg dm^?3 N⁶-benzyladenine (BA) for induction of callus. Callus could be successfully induced from all the three explants of both the genotypes. But the high frequency of embryogenic callus could be induced only from immature inflorescence explants. Somatic embryos were formed from nodular, hard and compact embryogenic calli when 2,4-D concentration was gradually reduced and BA concentration increased. Histological studies of somatic embryos indicated the presence of shoot apical meristem with leaf primordia. Ultrastructural details of globular and scutellar somatic embryos further validated successful induction and progression of somatic embryogenesis. Shoots were differentiated upon germination of somatic embryos on MS medium containing 2,4-D (0.25 mg dm^?3) and BA or kinetin (1–5 mg dm^?3). Roots were induced on ½ MS medium containing charcoal (0.8 %), and the regenerated plants transferred to pots and established in the soil showed normal growth and fertility.     

A new species of psammosteiform heterostracan (Agnatha) from the Givetian (Middle Devonian) of the Voronezh Region

A new pycnosteid species, Schizosteus shkurlatensis sp. nov. (Agnatha, Psammosteiformes), from the Staryi Oskol beds (Givetian, Middle Devonian) of the Voronezh Region is described. This is the first species of the genus Schizosteus Obruchev from the Central Devonian Field. The similarity between species of this genus and early species of Psammolepis is discussed.     

<Emphasis Type="Italic">Oredezhosteus</Emphasis>, a new psammosteid genus (Heterostraci,Psammosteiformes) from the Lower Frasnian (Upper Devonian) of the Main Devonian Field

A new psammosteid, Oredezhosteus kuleshovi gen. et sp. nov., from the Amata Regional Stage (Lower Frasnian) of the Leningrad Region is described. In addition, Psammosteus livonicus Obruchev from beds of the same age from Latvia is included in the new genus. The major diagnostic characters distinguishing Oredezhosteus gen. nov. from Psammosteus Agassiz are the large rounded striated tubercles, which cover more than half width of the branchials, and the long base of the branchial plates.     

多鳃鱼类一新属及该类鱼感觉沟系统的变异

本文记述了云南曲靖早泥盆世翠峰山组西山村段多鳃鱼类一新属种,变异坝鱼(Damaspis vartus gen.et sp.nov.)文中讨论了多鳃鱼类头甲背部感觉沟系统的基本模式,它的变化和变异。从这个基本模式出发笔者认为三岔鱼科和多鳃鱼科有许多重要的特征相近,似乎应把三岔鱼科和多鳃鱼科隶属于同一个高一级的分类单元即多鳃鱼目,而不应把三岔鱼科置于“华南鱼目”。“华南鱼目”是根据了解还不多的华南鱼属建立的,有些勉强,建议暂不采用。文中首次指出多鳃鱼类的感觉沟系统存在变异现象并认为在确立新类型时,变异是应该考虑的一个重要因素。     

盔甲鱼类Antiquisagittaspis cornuta(新属、新种)在广西六景下泥盆统的发现

本文记述了盔甲鱼类三岔鱼科 (sanchaspidae) —新属 Antiquisagittaspis 并对含鱼层时代作了对比;同时对中背孔和盔甲鱼类的生活环境作了评述.     

A new genus of quill mites of the family Syringophilidae (Acari: Cheyletoidea) associated with mousebirds (Aves: Coliiformes)

A new monotypic genus Colisyringophilus n. g. is established for C. tanzanicus n. sp., quill mites parasitising two mouse bird species from Tanzania, Colius striatus Gmelin and Urocolius macrourus (Linnaeus). This new genus is closely related to Neoaulobia Fain, Bochkov & Mironov, 2000, but differs from it by the following features: the stylophore is rounded posteriorly, the propodonotal shield is reduced to triangular sclerite bearing bases of setae vi and ve, the hysteronotal shield is absent, legs I are longer than legs II, and apodemes I are distinctly elongated. This is the first record of syringophilid mites from hosts of the order Coliiformes.     

Early Tithonian entactinarian Radiolaria from the Solnhofen area (southern Germany). Part I

The article describes part of the Entactinaria radiolarians from a very rich and well-preserved radiolarian assemblage extracted from a lower Tithonian sample (Mue 22) collected from the Mühlheim Member of the Mörnsheim Formation of southern Germany. With a single exception (genus Odoghertites nov. gen.), all other Entactinaria described are of primitive type, that is their initial spicules are not differentiated into an apical and a basal group and are not connected by arches to form a heteropolar “microsphere”. They have been assigned to five families, four of which are new (Isometractiniidae, Triumbraculidae, Hollandocachoniidae, Odoghertitidae), 10 new genera (Isometractinia, Triumbraculum, Tardentactinia, Lententactinia, Hollandocachonia, Sphaerentofurca, Stylentofurca, Zuegelifurca, Spongentofurca, Odoghertites), and 19 new species. One of the new species comes from the lower Bajocian of Oregon. A new skeletal structural term, support structure, is introduced as a special type of connection between the primary spines and the macrosphere or cortical shell.     

A new chinchilloid (Rodentia,Hystricognathi) from the early Miocene of the localities of Bryn Gwyn and Gran Barranca (Patagonia,Argentina)

A new genus and species of chinchilloid rodent is described here. It was found in Colhuehuapian levels (early Miocene) of the localities of Bryn Gwyn and Gran Barranca, Chubut Province, Argentina. The new taxon shows a unique combination of characters (e.g., protohypsodont teeth, upper molars trilophodont, m1 and m2 tri- or tetralophodont with the second crest in position of variable development, and m3 trilophodont, cement absent) that make it different from any other known chinchilloids. We performed a phylogenetic analysis to corroborate the relationships of the new taxon within the Chinchilloidea. Our results indicate that the new taxon is best classified as Chinchilloidea incertae sedis, together with Incamys, Garridomys, and Scotamys. These species form the basal stock that leads to the modern lineage Chinchillidae (chinchillas and viscachas). The presence of the new taxon in these localities increases the diversity of chinchilloids during the early Miocene and reduces the dissimilarity between the faunas found in Bryn Gwyn and Gran Barranca.     

First record of non-marine ostracods from the Paleogene “hamadian deposits” of Méridja area,west of Bechar (southwestern Algeria)

A new non-marine ostracod fauna from the Paleogene “hamadian deposits” outcropping west of Bechar (southwestern Algeria) has been recovered from lacustrine to fluvial deposits of the Oued Méridja section and fluvial deposits on the southern edge of the Hamada de Méridja section. Recently, these sections have been dated as late Thanetian – early Ypresian (latest Paleocene to earliest Eocene) and Ypresian – earliest Lutetian (early to earliest middle Eocene), respectively, based on charophytes. The associated ostracod fauna recovered consists of relatively mostly moderately to badly preserved specimens and comprises 14 taxa, none of which could be identified to species level in view of its poor state of preservation; we have nevertheless been able to identify and describe the following taxa: Herpetocypris sp., Cyprinotus? sp., Heterocypris? sp. 1 and sp. 2, Cypris? sp., Ilyocypris sp., Cytheroidea indet. sp. 1 and sp. 2, Limnocytheridae indet. sp. 1, Cypridoidea indet. sp. 1, Cyprididae indet. sp. 1, and Ostracoda indet. sp. 1, 2 and 3. Only Heterocypris sp. 1 occurs in both sections. Although the fauna can as yet not be related to the few other contemporaneous faunas reported from the wider palaeogeographic area, it adds important new information to our poor knowledge on Eocene non-marine ostracods in North Africa and southern Europe. The Méridja sections and area are promising regarding the discovery of more, better preserved material and further studies, and one main limitation to the correlation of the fauna is the hitherto insufficient taxonomic knowledge on many faunal elements of Eocene non-marine ostracods to which our section contributes considerably.     

The postparietal shield of the Pragian dipnomorph Arquatichthys and its implications for the rhipidistian cranial anatomy

Rhipidistians comprise dipnomorphs (the lungfish lineage) and tetrapodomorphs (the tetrapod lineage). Arquatichthys porosus Lu and Zhu, 2008 is a Pragian dipnomorph from the Posongchong Formation of Zhaotong, Yunnan, South China (∼409 million years ago, Early Devonian), previously represented by a lower jaw and few scattered scales. Here we describe a newly-discovered postparietal shield of Arquatichthys by means of high-resolution computed tomography. The cranial morphology of Arquatichthys resembles that of the basal dipnomorph Powichthys in having more than two supratemporal bones each side, more than one row of openings for sensory canals on the marginal bones, and a straight posterior margin of the shield. An intricate occipital artery system is present between the skull roof and neurocranium, as in Youngolepis and the tetrapodomorph Eusthenopteron. The discovery of the postparietal shield of Arquatichthys adds new evidence in the cranial evolution of rhipidistians, and helps to improve our understanding of the character transformations during the early diversification of rhipidistians.     

A new kogaionid multituberculate mammal from the Maastrichtian of the Transylvanian Basin,Romania

The Latest Cretaceous (Maastrichtian) terrestrial sedimentary sequences of the Haţeg Basin in Transylvania are well known for the so-called “Haţeg Island” vertebrate faunas, which evolved in endemic (insular?) conditions. In addition to frogs, lizards, turtles, crocodilians, birds and dinosaurs, peculiar multituberculate mammals have been recorded, all belonging to the family Kogaionidae. Here, a new species of the genus Barbatodon is reported from the Maastrichtian Şard Formation in the Transylvanian Basin (Alba County, Romania). Barbatodon oardaensis n. sp. is characterized by M1 cusp formula 3:4:2 and is much smaller than the two other Maastrichtian kogaionids from Transylvania, Barbatodon transylvanicus and Kogaionon ungureanui. The origin and paleobiogeography of kogaionids are discussed.     

Complete Genome Sequencing of Four Geographically Diverse Strains of Batai Virus

Batai virus (BATV) is a widely distributed but poorly studied member of the Orthobunyavirus genus in the family Bunyaviridae and is of particular interest as a known participant in natural reassortment events. Both research and surveillance efforts on this and other related viruses have been hampered by the lack of available full-length sequence data covering all three genomic segments. Here, we report the complete genome sequence of four BATV strains (MM2222, Chittoor/IG-20217, UgMP-6830, and MS50) isolated from various geographical locations. Based on these data, we have determined that strain MS50 is in fact unrelated to BATV and likely represents as a novel genotype in the genus Orthobunyavirus.