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Crustaceana ◽  
2021 ◽  
Vol 94 (11-12) ◽  
pp. 1313-1325
Author(s):  
Elisabeth Mock ◽  
Christoph D. Schubart

Abstract The genus Metopograpsus H. Milne Edwards, 1853 is widespread throughout the Indo-West Pacific and currently consists of seven species that can only be separated by minor morphological differences. Therefore, it represents a good example for the usefulness of genetic analyses for identification and classification. In order to obtain phylogenetic information at both lower and higher evolutionary levels, it is best to use a combination of mitochondrial and nuclear molecular markers. Here we present for the first time a molecular phylogeny based on a relative long fragment of the 28S rRNA nuclear gene for the genus Metopograpsus, after application of newly developed primers. Our data suggest an alternative intrageneric speciation order, with M. thukuhar and M. cannicci holding a basal position and a monophyletic grouping of M. frontalis, M. oceanicus and M. quadridentatus, which differs from prior phylogenetic reconstructions. Previously recognized intraspecific phylogeographic patterns in M. latifrons and M. quadridentatus could not be confirmed, due to limited variability of this conserved nuclear gene and due to an incomplete geographic coverage of the corresponding species. In contrast, the previously indicated phylogenetic subdivision within the formerly widespread species M. thukuhar, which led to the recent description of M. cannicci, is here supported.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12465
Author(s):  
Nian Gong ◽  
Lin Yang ◽  
Xiangsheng Chen

Here, the complete mitochondrial genomes (mitogenomes) of 12 Caliscelidae species, Augilina tetraina, Augilina triaina, Symplana brevistrata, Symplana lii, Neosymplana vittatum, Pseudosymplanella nigrifasciata, Symplanella brevicephala, Symplanella unipuncta, Augilodes binghami, Cylindratus longicephalus, Caliscelis shandongensis, and Peltonotellus sp., were determined and comparatively analyzed. The genomes varied from 15,424 to 16,746 bp in size, comprising 37 mitochondrial genes and an A+T-rich region. The typical gene content and arrangement were similar to those of most Fulgoroidea species. The nucleotide compositions of the mitogenomes were biased toward A/T. All protein-coding genes (PCGs) started with a canonical ATN or GTG codon and ended with TAN or an incomplete stop codon, single T. Among 13 PCGs in 16 reported Caliscelidae mitogenomes, cox1 and atp8 showed the lowest and highest nucleotide diversity, respectively. All PCGs evolved under purifying selection, with atp8 considered a comparatively fast-evolving gene. Phylogenetic relationships were reconstructed based on 13 PCGs in 16 Caliscelidae species and five outgroups using maximum likelihood and Bayesian inference analyses. All species of Caliscelidae formed a steadily monophyletic group with high support. Peltonotellini was present at the basal position of the phylogenetic tree. Augilini was the sister group to Caliscelini and Peltonotellini.


Author(s):  
Simon J. Braddy ◽  
Jason A. Dunlop ◽  
Joseph A. Bonsor

The stylonurid eurypterid Leiopterella tetliei Lamsdell, Braddy, Loeffler, and Dineley, 2010 (Chelicerata: Eurypterida: Rhenopteridae) from the Early Devonian (Lochkovian) of Nunavut in Arctic Canada is redescribed. Restudy of the holotype under polarized light revealed a labrum, epistomal sutures, prosomal appendage III, and deltoid plates anterior to the genital appendage. An additional new specimen preserves the distal podomeres of appendage VI and gradually tapering opisthosomal tergites. The characters resolved here support the hypothesis that L. tetliei was relatively basal within the wider Stylonurina clade, with its tapering postabdomen supporting a more basal position within Rhenopteridae than previously suggested.


2021 ◽  
Vol 8 (8) ◽  
pp. 210643
Author(s):  
Ben Thuy ◽  
Lea D. Numberger-Thuy ◽  
Tania Pineda-Enríquez

Understanding of the evolutionary history of the ophiuroids, or brittle stars, is hampered by a patchy knowledge of the fossil record. Especially, the stem members of the living clades are poorly known, resulting in blurry concepts of the early clade evolution and imprecise estimates of divergence ages. Here, we describe new ophiuroid fossil from the Lower Jurassic of France, Luxembourg and Austria and introduce the new taxa Ophiogojira labadiei gen. et sp. nov. from lower Pliensbachian shallow sublittoral deposits, Ophiogojira andreui gen. et sp. nov. from lower Toarcian shallow sublittoral deposits and Ophioduplantiera noctiluca gen. et sp. nov. from late Sinemurian to lower Pliensbachian bathyal deposits. A Bayesian morphological phylogenetic analysis shows that Ophiogojira holds a basal position within the order Ophiurida, whereas Ophioduplantiera has a more crownward position within the ophiurid family Ophiuridae. The position of Ophioduplantiera in the evolutionary tree suggests that family-level divergences within the Ophiurida must have occurred before the late Sinemurian, and that ancient slope environments played an important role in fostering early clade evolution.


2021 ◽  
Vol 12 ◽  
Author(s):  
Atef Omar ◽  
Ji Hye Moon ◽  
Seung Won Nam ◽  
Jae-Ho Jung

Tunicothrix halophila n. sp. was discovered in a hypersaline marine sample from Jeju Island, Korea. It is characterized by the highly reduced number of dorsal bristles. In addition, the main character of the genus Tunicothrix (e.g., alveolar layer) is absent/indistinct. To figure out its identity and phylogenetic relationship, we examined the new species based on modern morphological methods and molecular phylogenetic analyses. Since the parabirojimids are of basal position to core hypotrichs and a smaller data set could show incorrect phylogenetic relationships among the hypotrichs, we used a huge data set composed of 1,460 DNA sequences to infer the phylogenetic tree. The reduction of dorsal bristles is very likely a secondarily evolved character in hypotrichs, resulting in the independent phenotypic adaptation in the hypersaline ecosystems as shown in other hypersaline hypotrichs. Furthermore, the so-called right marginal row 1 in other congeners is found to produce a pretransverse and transverse cirrus and thus we recommend using the term frontoventral row. Based on our data, we can justify Tunicothrix halophila n. sp. as a new species; however, despite the phenotypic distinctiveness, we refrain to establish a new genus because of the missing data and the non-monophyly of Tunicothrix.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jorgo Ristevski ◽  
Gilbert J. Price ◽  
Vera Weisbecker ◽  
Steven W. Salisbury

AbstractBased on the known fossil record, the majority of crocodylians from the Cenozoic Era of Australia are referred to the extinct clade Mekosuchinae. The only extant crocodylians in Australia are two species of Crocodylus. Hence, the viewpoint that Crocodylus and mekosuchines have been the only crocodylians inhabiting Australia during the Cenozoic has remained largely undisputed. Herein we describe Australia’s first tomistomine crocodylian, Gunggamarandu maunala gen. et sp. nov., thus challenging the notion of mekosuchine dominance during most of the Cenozoic. The holotype specimen of Gunggamarandu maunala derives from the Pliocene or Pleistocene of south-eastern Queensland, marking the southern-most global record for Tomistominae. Gunggamarandu maunala is known from a large, incomplete cranium that possesses a unique combination of features that distinguishes it from other crocodylians. Phylogenetic analyses place Gunggamarandu in a basal position within Tomistominae, specifically as a sister taxon to Dollosuchoides from the Eocene of Europe. These results hint at a potential ghost lineage between European and Australian tomistomines going back more than 50 million years. The cranial proportions of the Gunggamarandu maunala holotype specimen indicate it is the largest crocodyliform yet discovered from Australia.


2021 ◽  
Author(s):  
Ben Thuy ◽  
Lea D. Numberger-Thuy ◽  
Tania Pineda-Enriquez

Understanding of the evolutionary history of the ophiuroids, or brittle stars, is hampered by a patchy knowledge of the fossil record. Especially the stem members of the living clades are poorly known, resulting in blurry concepts of the early clade evolution and imprecise estimates of divergence ages. Here, we describe new ophiuroid fossil from the Lower Jurassic of France, Luxembourg, and Austria and introduce the new taxa Ophiogojira labadiei gen. et sp. nov. from lower Pliensbachian shallow sublittoral deposits, Ophiogojira andreui gen. et sp. nov. from lower Toarcian shallow sublittoral deposits, and Ophioduplantiera noctiluca gen. et sp. nov. from late Sinemurian to lower Pliensbachian bathyal deposits. A Bayesian morphological phylogenetic analysis shows that Ophiogojira holds a basal position within the order Ophiurida, whereas Ophioduplantiera has a more crownward position within the ophiurid family Ophiuridae. The position of Ophioduplantiera in the evolutionary tree suggests that family-level divergences within the Ophiurida must have occurred before the late Sinemurian, and that ancient slope environments played an important role in fostering early clade evolution.


Author(s):  
Aleksey V. Kachalkin ◽  
Dinakhanum A. Abdullabekova ◽  
Elena S. Magomedova ◽  
Andrey M. Yurkov

During an investigation of the yeast communities associated with wild fruit shrubs in Dagestan (Caucasus, Russia), four fermenting ascospore-producing yeast strains were isolated from leaves of the Georgian honeysuckle (Lonicera iberica M. Bieb.) and from soil underneath this plant. Phylogenetic analyses based on concatenated sequences of the ITS region and D1/D2 domains of the large subunit rRNA gene and concatenated sequences of the ribosomal DNA cystron, RPB2 and TEF1 genes showed that the isolated strains represented a new species of the genus Zygotorulaspora. The new species was placed in the basal position to other species of the clade and close to Zygotorulaspora mrakii. Based on the results of phylogenetic analyses and the phenotypic characteristics of the four studied strains, a novel species is described, for which the name Zygotorulaspora dagestanica sp. nov. is proposed. The holotype is KBP Y-4591T, three metabolically inactive cryopreserved isotype cultures are DSM 100088, VKM Y-3060 and VKPM Y-4318. The MycoBank number is MB 838285.


Zootaxa ◽  
2021 ◽  
Vol 4952 (2) ◽  
pp. 331-353
Author(s):  
CHAO YANG ◽  
LE ZHAO ◽  
QINGXIONG WANG ◽  
HAO YUAN ◽  
XUEJUAN LI ◽  
...  

To gain a better understanding of mitogenome features and phylogenetic relationships in Sylvioidea, a superfamily of Passerida, suborder Passeri, Passeriformes, the whole mitogenome of Alaudala cheleensis Swinhoe (Alaudidae) was sequenced, a comparative mitogenomic analysis of 18 Sylvioidea species was carried out, and finally, a phylogeny was reconstructed based on the mitochondrial dataset. Gene order of the A. cheleensis mitogenome was similar to that of other Sylvioidea species, including the gene rearrangement of cytb-trnT-CR1-trnP-nad6-trnE-remnant CR2-trnF-rrnS. There was slightly higher A+T content than that of G+C in the mitogenome, with an obvious C skew. The ATG codon initiated all protein-coding genes, while six terminating codons were used. The secondary structure of rrnS contained three domains and 47 helices, whereas rrnL included six domains and 60 helices. All tRNAs could be folded into a classic clover-leaf secondary structure except for trnS (AGY). The CR1 could be divided into three domains, including several conserved boxes (C-string, F, E, D, C and B-box, Bird similarity box, CSB1). Comparative analyses within Sylvioidea mitogenomes showed that most mitochondrial features were consistent with that of the A. cheleensis mitogenome. The basal position of the Alaudidae within the Sylvioidea in our phylogenetic analyses is consistent with other recent studies. 


2021 ◽  
Vol 72 (1) ◽  
Author(s):  
Takayuki Kohchi ◽  
Katsuyuki T. Yamato ◽  
Kimitsune Ishizaki ◽  
Shohei Yamaoka ◽  
Ryuichi Nishihama

Bryophytes occupy a basal position in the monophyletic evolution of land plants and have a life cycle in which the gametophyte generation dominates over the sporophyte generation, offering a significant advantage in conducting genetics. Owing to its low genetic redundancy and the availability of an array of versatile molecular tools, including efficient genome editing, the liverwort Marchantia polymorpha has become a model organism of choice that provides clues to the mechanisms underlying eco-evo-devo biology in plants. Recent analyses of developmental mutants have revealed that key genes in developmental processes are functionally well conserved in plants, despite their morphological differences, and that lineage-specific evolution occurred by neo/subfunctionalization of common ancestral genes. We suggest that M. polymorpha is an excellent platform to uncover the conserved and diversified mechanisms underlying land plant development. Expected final online publication date for the Annual Review of Plant Biology, Volume 72 is May 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


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