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PhytoKeys ◽  
2021 ◽  
Vol 187 ◽  
pp. 77-92
Author(s):  
Dan-Hui Liu ◽  
Xue-Min Xu ◽  
Yi He ◽  
Quan-Ru Liu

Lappula sinaica was recently transferred to the monotypic genus Pseudolappula based on phylogenetic studies, while the related species, L. occultata, has remained in the genus Lappula. In this study, morphological, molecular, and palynological evidence supports that L. occultata should be transferred to the genus Pseudolappula. Both L. occultata and P. sinaica share a combination of nutlets features that distinguish them from Lappula: a longer adaxial keel and a linear attachment scar. Phylogenetic analysis based on ITS and trnL-F strongly supports L. occultata as the sister taxon of P. sinaica. In addition, pollen grains of these two species are 3-syncolporate with 3 alternating pseudocolpi, which is significantly different from the grains of Lappula taxa. Based on the above evidence, the new combination Pseudolappula occultata is proposed.


2021 ◽  
Vol 9 ◽  
Author(s):  
Juan C. Cisneros ◽  
Paula Dentzien-Dias ◽  
Heitor Francischini

Provelosaurus americanus is the only known representative of the Pareiasauria in the Americas. This mid-size pareiasaur from the Rio do Rasto Formation of southern Brazil has been traditionally considered to be related to smaller forms from the South African Karoo known as the “dwarf pareiasaurs” of Lopingian age. P. americanus, however, co-existed with dinocephalians, which indicates a Guadalupian age. New fossils provide a nearly complete osteological account that forms the basis for a revised diagnosis and a test of phylogenetic relationships of P. americanus. Our results offer further support to the hypothesis that the Brazilian pareiasaur is the sister taxon of the Karoo “dwarf pareiasaurs,” being the earliest member of this group and one of the oldest pareiasaurs known so far. This is reinforced by a radiometric dating of the Morro Pelado Member of the Rio do Rasto Formation. In addition, the association of four individuals of various ontogenetic stages at the type locality supports some degree of social behavior in P. americanus.


2021 ◽  
Author(s):  
Andrej Čerňanský ◽  
Edward L. Stanley ◽  
Juan D. Daza ◽  
Arnau Bolet ◽  
J. Salvador Arias ◽  
...  

Abstract We here report on a well-preserved juvenile lizard specimen in Albian amber (ca. 110 mya) from the Hkamti site in Myanmar. This new taxon, Retinosaurus hkamtiensis gen. et sp. nov., is represented by an articulated skull and the anterior portion of the trunk, including the pectoral girdle and forelimbs. The ocular skeleton (scleral ossicles) and eyelid are also visible, and the specimen exhibits pristine detail of the integument (of both head and body). In a combined molecular and morphological analysis, Retinosaurus was consistently recovered as a scincoid lizard (i.e. Scinciformata), as the sister taxon to the Mexican Cretaceous genus Tepexisaurus + Xantusiidae. However, the phylogenetic position of Retinosaurus should be interpreted with caution. We cannot not rule out the possibility that Retinosaurus represents a separate lineage of uncertain phylogenetic position, as it is the case for many Jurassic and Cretaceous taxa. Nonetheless, this fossil offers a rare opportunity to glimpse the external appearance of one group of lizards during the Early Cretaceous.


Zootaxa ◽  
2021 ◽  
Vol 5048 (4) ◽  
pp. 581-593
Author(s):  
SHRUTI SENGUPTA ◽  
JAYADITYA PURAKAYASTA ◽  
NITESH ANANDAN ◽  
MADHURIMA DAS ◽  
KIN ONN CHAN ◽  
...  

Herein we provide new information on Cnemaspis assamensis, the only species of Cnemaspis known from north-eastern India.  Based on five new samples, morphological parameters are described. The species was found to have pre-cloacal and femoral pores, not accounted for in the original description. Genetic assessment of the species was made using a 914 bp fragment of the ND2 mitochondrial gene and the species was recovered as the sister taxon of the C. podihuna clade from Sri Lanka.  


Author(s):  
Gerald Mayr

AbstractA partial skeleton of the putative stem group roller Septencoracias is described from the early Eocene London Clay of Walton-on-the-Naze (Essex, UK). With an age of about 55 million years, the bones represent one of the earliest fossil records of a coraciiform bird. The new fossil reveals that the proximal pedal phalanges of the three anterior toes of Septencoracias exhibit markedly widened distal ends. This distinctive trait is not found in other representatives of the Coracii, but occurs in the Meropidae (bee-eaters). The quadrate likewise exhibit a derived characteristic of the Meropidae, and the beak is narrower than in rollers. These previously unnoticed features are of particular interest, because the Meropidae result as the sister taxon of the Coracii in sequence-based analyses. Calibrated molecular data suggest that the divergence between the Coracii and the Meropidae occurred at 55.6 Ma, with the new fossil being only slightly younger than this date. However, phylogenetic analyses recovered Septencoracias within the Coracii, so that the derived features shared with the Meropidae most likely are either plesiomorphic and were lost in the Coracii, or they represent parallelisms that evolved convergently in Septencoracias and the Meropidae. In any case, these traits suggest that Septencoracias differed from extant rollers in its ecological preferences and foraging mode.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12094
Author(s):  
Jonathan P. Rio ◽  
Philip D. Mannion

First appearing in the latest Cretaceous, Crocodylia is a clade of semi-aquatic, predatory reptiles, defined by the last common ancestor of extant alligators, caimans, crocodiles, and gharials. Despite large strides in resolving crocodylian interrelationships over the last three decades, several outstanding problems persist in crocodylian systematics. Most notably, there has been persistent discordance between morphological and molecular datasets surrounding the affinities of the extant gharials, Gavialis gangeticus and Tomistoma schlegelii. Whereas molecular data consistently support a sister taxon relationship, in which they are more closely related to crocodylids than to alligatorids, morphological data indicate that Gavialis is the sister taxon to all other extant crocodylians. Here we present a new morphological dataset for Crocodylia based on a critical reappraisal of published crocodylian character data matrices and extensive firsthand observations of a global sample of crocodylians. This comprises the most taxonomically comprehensive crocodylian dataset to date (144 OTUs scored for 330 characters) and includes a new, illustrated character list with modifications to the construction and scoring of characters, and 46 novel characters. Under a maximum parsimony framework, our analyses robustly recover Gavialis as more closely related to Tomistoma than to other extant crocodylians for the first time based on morphology alone. This result is recovered regardless of the weighting strategy and treatment of quantitative characters. However, analyses using continuous characters and extended implied weighting (with high k-values) produced the most resolved, well-supported, and stratigraphically congruent topologies overall. Resolution of the gharial problem reveals that: (1) several gavialoids lack plesiomorphic features that formerly drew them towards the stem of Crocodylia; and (2) more widespread similarities occur between species traditionally divided into tomistomines and gavialoids, with these interpreted here as homology rather than homoplasy. There remains significant temporal incongruence regarding the inferred divergence timing of the extant gharials, indicating that several putative gavialids (‘thoracosaurs’) are incorrectly placed and require future re-appraisal. New alligatoroid interrelationships include: (1) support for a North American origin of Caimaninae in the latest Cretaceous; (2) the recovery of the early Paleogene South American taxon Eocaiman as a ‘basal’ alligatoroid; and (3) the paraphyly of the Cenozoic European taxon Diplocynodon. Among crocodyloids, notable results include modifications to the taxonomic content of Mekosuchinae, including biogeographic affinities of this clade with latest Cretaceous–early Paleogene Asian crocodyloids. In light of our new results, we provide a comprehensive review of the evolutionary and biogeographic history of Crocodylia, which included multiple instances of transoceanic and continental dispersal.


Zootaxa ◽  
2021 ◽  
Vol 5023 (1) ◽  
pp. 93-106
Author(s):  
QUYEN HANH DO ◽  
KHOI VU NGUYEN ◽  
MINH DUC LE ◽  
CUONG THE PHAM ◽  
THOMAS ZIEGLER ◽  
...  

We describe a new species of the genus Hemiphyllodactylus on the basis of four specimens from Bidoup - Nui Ba National Park, Da Lat Plateau, Lam Dong Province, Vietnam. The new species, Hemiphyllodactylus dalatensis sp. nov., is distinguished from the remaining congeners by a combination of the following characters: a bisexual taxon; maximum SVL of 45.9 mm; dorsal scale rows 16; ventral scale rows 8 or 9; chin scales 7–10; postmental scales enlarged; femoral and precloacal pores in a continuous series, 23–25 in total in males, absent in the female; digital lamellae formula 4-5-5/6-5 (forefoot) and 5-6-6-6/5 (hind foot); cloacal spurs 2 or 3 on each side in both males and female; subcaudal scales not enlarged; dorsal trunk pattern with two paravertebral stripes, formed by two rows of dark spots; dark lateral head stripe distinct; postsacral mark cream or orange and bearing anteriorly projecting arms. In phylogenetic analyses, the new species is recovered as the sister taxon to a clade including all species from India although support values are low from all analyses.  


Zootaxa ◽  
2021 ◽  
Vol 4995 (1) ◽  
pp. 147-160
Author(s):  
TAIKI ITO ◽  
KAZUO HOSHINO ◽  
KAZUMI HOSOYA

Hemigrammocypris neglecta is a small-sized cyprinid fish that is endemic to Japan and the sole member of the genus Hemigrammocypris. We examined the osteological features of the species, and its relationships with related genera are discussed. The present data suggest that H. neglecta is most likely the sister taxon of Metzia lineata. This relationship is supported by one possible synapomorphy: the presence of a postepiphysial fontanelle, which is absent in all other Xenocypridinae.  


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.


Zootaxa ◽  
2021 ◽  
Vol 4965 (2) ◽  
pp. 351-362
Author(s):  
THUONG HUYEN NGUYEN ◽  
VINH QUANG LUU ◽  
SALY SITTHIVONG ◽  
HANH THI NGO ◽  
TRUONG QUANG NGUYEN ◽  
...  

A new species of the gekkonid genus Dixonius is described from Huaysorn-Huaysua village, Nasaithong District, Vientiane Capital, Laos. The new species can be distinguished from all other species by a combination of the following characters: maximum SVL 47.1 mm; 19–21 longitudinal rows of dorsal tubercles at midbody; 23–26 longitudinal rows of ventrals across the abdomen; 7 or 8 supralabials, 6 in mid-orbital position; 5 or 6 infralabials; 5 or 6 precloacal pores in males, femoral pores lacking; precloacal and femoral pores absent in females; a canthal stripe running from rostrum through the eye and terminating at back of head; dorsum brown with irregular dark marks. In phylogenetic analyses, the species is recovered as the sister taxon to D. siamensis, which occurs in Laos, Thailand, and Vietnam. Genetically, the two species are approximately 9.4% divergent from each other based on the complete mitochondrial ND2 gene with six partial or complete adjacent tRNAs. It is the 12th species known in the genus Dixonius and the second Dixonius species described from Laos. 


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