Circumscription of Fulbrightiella gen. nov. and Sherwoodiella gen. nov., Two Novel Genera in the Calotrichaceae (Nostocales,Cyanobacteria)

Three novel strains in Calotrichaceae from tropical habitats were isolated and characterized with regard to their morphology, phylogenetic placement, and secondary structures of conserved domains in the 16S-23S internal transcribed spacer (ITS). The strains fell into two clades formerly identified as Calothrix from freshwater and brackish habitats. Based on both morphology and ecology, they differed from the type species of Calothrix, C. confervicola, which is marine, has wide trichomes with short cells, and narrows abruptly to a hyaline hair. The first clade grouped species with heteropolar filaments widened at the base and narrowed gradually toward the apex but not ending in a hair, with basal heterocytes that are formed in series as the apically placed heterocytes senesce; this clade is being named Fulbrightiella gen. nov., with two named species, F. bharadwajae sp. nov. and F. oahuensis sp. nov. The second clade was comprised of a single species with isopolar trichomes that are untapering as hormogonia, but which widen midfilament and taper toward both ends following growth. These trichomes develop pairs of heterocyte mid-filament, causing fragmentation into heteropolar trichomes with basal heterocytes and ends that taper, but not to a hair. This clade consists of a single species at present, Sherwoodiella mauiensis. With this action, four clades in the Calotrichaceae have been named: Macrochaete, Dulcicalothrix, Fulbrightiella, and Sherwoodiella. Calothrix sensu stricto is truly marine, morphologically distinct, and unsequenced; finding and sequencing the generitype for Calothrix remains as the most important and unfinished task in the revision of the Calotrichaceae.     

Cyanomargarita gen. nov. (Nostocales,Cyanobacteria): convergent evolution resulting in a cryptic genus

Two populations of Rivularia‐like cyanobacteria were isolated from ecologically distinct and biogeographically distant sites. One population was from an unpolluted stream in the Kola Peninsula of Russia, whereas the other was from a wet wall in the Grand Staircase‐Escalante National Monument, a desert park‐land in Utah. Though both were virtually indistinguishable from Rivularia in field and cultured material, they were both phylogenetically distant from Rivularia and the Rivulariaceae based on both 16S rRNA and rbcLX phylogenies. We here name the new cryptic genus Cyanomargarita gen. nov., with type species C. melechinii sp. nov., and additional species C. calcarea sp. nov. We also name a new family for these taxa, the Cyanomargaritaceae.     

Freshwater occurrence of the extinct dolphin Parapontoporia (Cetacea: Lipotidae) from the upper Pliocene nonmarine Tulare Formation of California

The diminutive, extinct longirostrine dolphin Parapontoporia is one of the most abundantly represented late Neogene odontocetes from the eastern North Pacific and is widely known from numerous marine strata of late Miocene and Pliocene age in California, Baja California and possibly Japan. Parapontoporia has been identified as the sister taxon of the recently extinct Chinese river dolphin (Lipotes vexillifer); unlike Lipotes, which exclusively inhabited freshwater, the depositional context of Parapontoporia suggests it was marine. A newly identified petrosal of Parapontoporia sp. was preserved alongside terrestrial vertebrates in the nonmarine Tulare Formation (upper Pliocene to Pleistocene, 2.2–0.6 Ma), California, which was deposited under lacustrine and fluviodeltaic conditions. Abundantly preserved freshwater molluscs and rare marine taxa suggest predominantly freshwater settings with intermittent periods of estuarine conditions. This occurrence of Parapontoporia indicates its presence in the San Joaquin basin after the retreat of the inland sea and suggests that this extinct odontocete may have been freshwater tolerant and an inhabitant of marine and freshwater settings, heralding the exclusively freshwater existence of its Recent sister taxon Lipotes vexillifer.     

Morphological and molecular characterization within 26 strains of the genus Cylindrospermum (Nostocaceae,Cyanobacteria), with descriptions of three new species

Twenty‐six strains morphologically identified as Cylindrospermum as well as the closely related taxon Cronbergia siamensis were examined microscopically as well as phylogenetically using sequence data for the 16S rRNA gene and the 16S‐23S internal transcribed spacer (ITS) region. Phylogenetic analysis of the 16S rRNA revealed three distinct clades. The clade we designate as Cylindrospermum sensu stricto contained all five of the foundational species, C. maius, C. stagnale, C. licheniforme, C. muscicola, and C. catenatum. In addition to these taxa, three species new to science in this clade were described: C. badium, C. moravicum, and C. pellucidum. Our evidence indicated that Cronbergia is a later synonym of Cylindrospermum. The phylogenetic position of Cylindrospermum within the Nostocaceae was not clearly resolved in our analyses. Cylindrospermum is unusual among cyanobacterial genera in that the morphological diversity appears to be more evident than sequence divergence. Taxa were clearly separable using morphology, but had very high percent similarity among ribosomal sequences. Given the high diversity we noted in this study, we conclude that there is likely much more diversity remaining to be described in this genus.     

The Miocene tortoise Testudo catalaunica Bataller, 1926, and a revised phylogeny of extinct species of genus Testudo (Testudines: Testudinidae)

We provide a taxonomic review of the extinct testudinid Testudo catalaunica, based on published and unpublished material from several Miocene (late Aragonian and early Vallesian) sites of the Vallès‐Penedès Basin (north‐east Iberian Peninsula). We show that Testudo catalaunica irregularis is a junior subjective synonym of T. catalaunica, and further provide an emended diagnosis of the latter based on newly reported material. Contrary to some recent suggestions, this emended diagnosis discounts an alternative attribution of T. catalaunica to Paleotestudo. The latter is merely recognized as a subgenus of Testudo, based on a cladistic analysis that assessed the phylogenetic position of all extant and most extinct species of Testudo currently recognized as valid (including T. catalaunica). Our phylogenetic analysis (which recovers the molecular phylogeny of extant Testudo s.l.) supports a taxonomic scheme in which the three extant subgenera of Testudo are represented in the fossil record. Testudo s.s. is retrieved as the sister taxon of Testudo (Agrionemys) + [Testudo (Paleotestudo) + Testudo (Chersine)]. The extinct Testudo (Paleotestudo) is therefore the sister taxon of the Testudo (Chersine) clade. The latter subgenus reveals as the most diverse clade of Testudo s.l. in the fossil record, with T. catalaunica + Testudo steinheimensis constituting a subclade distinct from that including Testudo hermanni.     

An investigation into the effects of increasing salinity on photosynthesis in freshwater unicellular cyanobacteria during the late Archaean

The oldest species of bacteria capable of oxygenic photosynthesis today are the freshwater Cyanobacteria Gloeobacter spp., belonging to the class Oxyphotobacteria. Several modern molecular evolutionary studies support the freshwater origin of cyanobacteria during the Archaean and their subsequent acquisition of salt tolerance mechanisms necessary for their expansion into the marine environment. This study investigated the effect of a sudden washout event from a freshwater location into either a brackish or marine environment on the photosynthetic efficiency of two unicellular freshwater cyanobacteria: the salt‐tolerant Chroococcidiopsis thermalis PCC7203 and the cyanobacterial phylogenetic root species, Gloeobacter violaceus PCC7421. Strains were cultured under present atmospheric levels (PAL) of CO₂ or an atmosphere containing elevated levels of CO₂ and reduced O₂ (eCO₂rO₂) in simulated shallow water or terrestrial environmental conditions. Both strains exhibited a reduction in growth rates and gross photosynthesis, accompanied by significant reductions in chlorophyll a content, in brackish water, with only C. thermalis able to grow at marine salinity levels. While the experimental atmosphere caused a significant increase in gross photosynthesis rates in both strains, it did not increase their growth rates, nor the amount of O₂ released. The differences in growth responses to increasing salinities could be attributed to genetic differences, with C. thermalis carrying additional genes for trehalose synthesis. This study demonstrates that, if cyanobacteria did evolve in a freshwater environment, they would have been capable of withstanding a sudden washout into increasingly saline environments. Both C. thermalis and G. violaceus continued to grow and photosynthesise, albeit at diminished rates, in brackish water, thereby providing a route for the evolution of open ocean‐dwelling strains, necessary for the oxygenation of the Earth's atmosphere.     

Pseudoparamoeba garorimi n. sp., with Notes on Species Distinctions within the Genus

A new marine species of naked lobose amoebae Pseudoparamoeba garorimi n. sp. (Amoebozoa, Dactylopodida) isolated from intertidal marine sediments of Garorim Bay, Korea was studied with light and transmission electron microscopy. This species has a typical set of morphological characters for a genus including the shape of the locomotive form, type of subpseudopodia and the tendency to form the single long waving pseudopodium in locomotion. Furthermore, it has the same cell surface structures as were described for the type species, Pseudoparamoeba pagei: blister‐like glycostyles with hexagonal base and dome‐shaped apex; besides, cell surface bears hair‐like outgrowths. The new species described here lacks clear morphological distinctions from the two other Pseudoparamoeba species, but has considerable differences in the 18S rDNA and COX1 gene sequences. Phylogenetic analysis based on 18S rDNA placed P. garorimi n. sp. at the base of the Pseudoparamoeba clade with high PP/BS support. The level of COX1 sequence divergence was 22% between P. garorimi n. sp. and P. pagei and 25% between P. garorimi n. sp. and P. microlepis. Pseudoparamoeba species are hardly distinguishable by morphology alone, but display clear differences in 18S rDNA and COX1 gene sequences.     

Odorella benthonica gen. & sp. nov. (Pleurocapsales,Cyanobacteria): an odor and prolific toxin producer isolated from a California aqueduct

Pleurocapsales are one of the least understood groups of cyanobacteria in terms of molecular systematics and biochemistry. Considering the high number of cryptic taxa within the Synechococcales and Oscillatoriales, it is likely that such taxa also occur in the Pleurocapsales. The new genus described in our research is the first known pleurocapsalean cryptic taxon. It produces off‐flavor and a large number of bioactive metabolites (n = 38) some of which can be toxic including four known microcystins. Using a polyphasic approach, we propose the establishment of the genus Odorella with the new species O. benthonica from material originally isolated from the California Aqueduct near Los Angeles.     

BRASILONEMA ANGUSTATUM SP. NOV. (NOSTOCALES), A NEW FILAMENTOUS CYANOBACTERIAL SPECIES FROM THE HAWAIIAN ISLANDS1

A new filamentous cyanobacterial species of the genus Brasilonema was isolated from the island of Oahu, Hawaii. The taxon is distinguished from the seven other species in the genus by attenuation of trichomes, and is here described as Brasilonema angustatum sp. nov. It possesses the cytoplasmic kerotimization and reddish‐brown coloration of several species in the genus. Phylogenetic analysis based on 16S rRNA gene sequence shows B. angustatum within a highly supported clade containing all sequenced Brasilonema species. We compared the secondary structure of the 16S–23S ITS regions for B. octagenarum and B. angustatum. The structurally conservative D1–D1′ and V3 helices show similar motifs between the two taxa, but differ structurally and in sequence, providing additional justification for erection of the new species. The Box‐B helix has identical secondary structure. The existence of tapering in a Brasilonema species is unique in this genus, and requires modification of the current concept of the genus Brasilonema, which was described as being unattenuated. Our phylogenetic evidence supports the hypothesis that tapering has developed repeatedly in separate cyanobacterial lineages and lacks the taxonomic significance once assumed by early workers.     

Phylogenetic relationships,song and distribution of the endangered Rufous‐headed Robin Larvivora ruficeps

The Rufous‐headed Robin Larvivora ruficeps is one of the world's rarest and least known birds. We summarize the known records since it was first described in 1905 from Shaanxi Province, central China. All subsequent Chinese records are from seven adjacent localities in nearby Sichuan Province. We studied its phylogenetic position for the first time using mitochondrial and nuclear markers for all species of Larvivora and a broad selection of other species in the family Muscicapidae. Our results confirmed that L. ruficeps is appropriately placed in the genus Larvivora, and suggested that it is sister to the Rufous‐tailed Robin Larvivora sibilans, with these two forming a sister clade to a clade comprising both the Japanese Robin Larvivora akahige and Ryukyu Robin Larvivora komadori. Siberian Blue Robin Larvivora cyane and Indian Blue Robin Larvivora brunnea form the sister clade to the other Larvivora species. In contrast, song analyses indicated that the song of L. ruficeps is most similar to that of L. komadori, whereas the song of L. sibilans is relatively more similar to that of L. akahige, and songs of L. cyane and L. brunnea closely resemble each other. We used ecological niche modelling to estimate the suitable habitats of L. ruficeps based on the records from breeding grounds, suggesting that north and central Sichuan, south Gansu, south Shaanxi and south‐east Tibet are likely to contain the most suitable habitats for this species.     

Glass in the water: Molecular phylogenetics and evolution of Indian glassy perchlets (Teleostei: Ambassidae)

Glassfishes of the family Ambassidae, comprising around 50 species, are distributed in the Indo‐West Pacific where they inhabit marine, estuarine, and freshwater ecosystems. We investigated for the first time the molecular phylogenetic and evolutionary relationships of this group using a combined dataset of mitochondrial and nuclear genes, particularly focusing on the taxa occurring in the Indian subcontinent. Results revealed that marine and freshwater genera of Ambassidae diverged during the Paleocene (~62 mya). The enigmatic monotypic genus Chanda is nested within the larger clade currently recognized as Parambassis, indicating its paraphyly. Based on cleared and stained osteological preparations and phylogenetic placement of Chanda nama, we hypothesize that the elongated and protruding lower jaw is an autapomorphic character that might have evolved for the lepidophagous habit of the species. The southern Indian species of Parambassis, Parambassis dayi, and Parambassis thomassi, which formed a monophyletic group, probably diverged from other species of Parambassis and Chanda nama around the Eocene (~42 mya) and can potentially be recognized as a distinct genus in view of the apomorphic characters such as the presence of serration on the ventral fringe of interopercle, densely serrated palatine and ectopterygoid, and the presence of more than 30 serrations along the lower preopercle and the posterior edge. Our analysis provides new insights into the evolution and phylogenetic relationships of glassy perchlets, including detailed relationships among the Indian species within this family.     

Potassium deficiency triggers the development of dormant cells (akinetes) in Aphanizomenon ovalisporum (Nostocales,Cyanoprokaryota)1

Akinetes are spore‐like nonmotile cells that differentiate from vegetative cells of filamentous cyanobacteria from the order Nostocales. They play a key role in the survival and distribution of these species and contribute to their perennial blooms. Various environmental factors were reported to trigger the differentiation of akinetes including light intensity and quality, temperature, and nutrient deficiency. Here, we report that deprivation of potassium ion (K⁺) triggers akinete development in the cyanobacterium Aphanizomenon ovalisporum. Akinetes formation is initiated 3 d–7 d after an induction by K⁺ depletion, followed by 2–3 weeks of a maturation process. Akinete formation occurs within a restricted matrix of environmental conditions such as temperature, light intensity or photon flux. Phosphate is essential for akinete maturation and P‐limitation restricts the number of mature akinetes. DNA replication is essential for akinete maturation and akinete development is limited in the presence of Nalidixic acid. While our results unequivocally demonstrated the effect of K⁺ deficiency on akinete formation in laboratory cultures of A. ovalisporum, this trigger did not cause Cylindrospermopsis raciborskii to produce akinetes. Anabaena crassa however, produced akinetes upon potassium deficiency, but the highest akinete concentration was achieved at conditions that supported vegetative growth. It is speculated that an unknown internal signal is associated with the cellular response to K⁺ deficiency to induce the differentiation of a certain vegetative cell in a trichome into an akinete. A universal stress protein that functions as mediator in K⁺ deficiency signal transduction cascade, may communicate between the lack of K⁺ and akinete induction.     

Mitogenomic phylogenetics of Diochus occultus n. sp., a palaeoendemic endogean species within the tribe Diochini (Coleoptera: Staphylinidae: Staphylininae)

The tribe Diochini has a worldwide distribution, with 2 and 74 epigean species within the genera Antarctothius and Diochus, respectively. Recent phylogenetic studies suggest a sister relationship of Diochini and a lineage formed by Xantholinini, Maorothiini, and Othiini, within the subfamily Staphylininae. Here, we describe the first known endogean representative of Diochini, Diochus occultus n. sp., and provide the first two complete mitogenomes for the tribe, corresponding to the two European Diochus species: Diochus occultus n. sp. and Diochus staudingeri. These sequences were combined with 40 additional mitogenomes from representatives within Staphylininae, Paederinae, Silphidae, and Aleocharinae, and COI sequences from 5 additional species of Diochus to conduct a series of mitogenomic phylogenetic and dating analyses. The estimated molecular phylogeny is fully consistent with previous studies based on morphology and molecular data, finding a sister relationship of Diochini with a clade formed by Xantholinini and Othiini (Maorothiini not sampled). Dating analyses inferred an early split of the tribe Diochini at 140–156 Mya. Morphology shows clear differences in the aedeagal and external morphology of D. occultus n. sp. and D. staudingeri, whereas a sister relationship of these taxa is found in the phylogenetic analyses, with the split dated at 48–61 Mya. Although the study of additional Palaearctic Diochus species will be required to conclusively establish that D. occultus n. sp. is a palaeoendemic taxon sister to D. staudingeri, associated with forests of Abies pinsapo in the south of the Iberian Peninsula, this conclusion is consistent with the ancient estimated age of speciation, endogean habitat specificity, low dispersal capacity (flightless species), and microendemicity of D. occultus. This is also consistent with the continued emersion of the Betic sub‐plate along its tectonic evolution. The estimated ages of diversification of the Paederinae‐Staphylininae lineage are also discussed.     

Do upstream migrating,juvenile amphidromous shrimps,provide a marine subsidy to river ecosystems?

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Relationship between the dinoflagellate cyst Spiniferites pachydermus and Gonyaulax ellegaardiae sp. nov. from Izmir Bay,Turkey, and molecular characterization

Here, we established the cyst‐motile stage relation‐ship for Spiniferites pachydermus through incubation of cysts with a characteristically microreticulate/perforate surface isolated from Izmir Bay in the eastern Aegean Sea of the eastern Mediterranean. The morphology of the motile stage was similar to Gonyaulax spinifera but had a different size, overhang, displacement and reticulations. Based on the distinct morphology of the cyst and morphological differences in motile cells, we assigned S. pachydermus from Izmir Bay to the new species Gonyaulax ellegaardiae. We elucidate the phylogenetic relationship of G. ellegaardiae through large and small subunit ribosomal DNA and show that it forms a clade with other species that belong to the G. spinifera complex.     

Reptodigitus Chapmanii (Nostocales,Hapalosiphonaceae) Gen. Nov.: A Unique Nostocalean (Cyanobacteria) Genus Based on a Polyphasic Approach1

The Nostocales is a monophyletic, heterocytous lineage of cyanobacteria capable of akinete production and division in multiple planes, depending upon family-level clade. While present in a variety of ecosystems, the diversity of the Nostocales has been poorly elucidated. Due to environmentally -induced phenotypic plasticity, morphology alone is often insufficient to determine the true phylogenetic placement of these taxa. In order to bridge this gap, taxonomists now employ the polyphasic approach, combining methods such as morphological analysis, phylogenetic analysis based on DNA sequence and genetic identity based on ribosomal genes, and secondary structure of the 16S-23S ITS and 16S rRNA gene sequences, as well as ecological characterization. Using this combined approach, a new genus and species (Reptodigitus chapmanii gen. et sp. nov.) isolated from the St. Johns River (Jacksonville, Florida, USA) within the Nostocales is herein described. Phylogenetic analyses place this taxon within the Hapalosiphonaceae, sister to the clade containing Fischerella, Hapalosiphon, and Westiellopsis. The 16S-23S ITS secondary folding structure analysis also supports the erection of this new genus.     

Systematics and phylogeny of Vasseuromys (Mammalia,Rodentia, Gliridae) with a description of a new species from the late Miocene of eastern Europe

Vasseuromys is a species‐rich genus of small‐ to medium‐sized glirids spanning the latest Oligocene to late Miocene of Europe and western Asia. Despite extensive discoveries over the past 50 years, little phylogenetic work has been done on Vasseuromys. This study presents the first phylogenetic analysis of the genus that includes all the described species and a new taxon Vasseuromys tectus sp. nov. from the late Miocene of eastern Europe, providing the first insights into the evolutionary relationships within the clade. Results suggest that the genus is clearly paraphyletic. Two strongly supported genus‐level clades are recognized within ‘Vasseuromys’: a restricted Vasseuromys clade (containing the three species, V. pannonicus, V. rugosus and V. tectus) and the Glirulus clade that includes ‘Vasseuromys’ duplex. The remaining ‘Vasseuromys’ species are found to constitute a set of paraphyletic taxa, with the polyphyletic ‘Ramys’ nested within it. The genus Gliruloides is synonymized with Glirulus. Vasseuromys tectus sp. nov. is the most derived member of the genus in having a greater number of cheek teeth ridges including constantly present anterotrope, centrotrope, second prototrope on M1–2, third metatrope on M2, two to three posterotropids on p4 and strong ectolophids on lower molars. The results of the study confirm a European origin for Vasseuromys while suggesting that the late Miocene species of the genus dispersed from the east in the early Turolian.