scholarly journals A revision of Prolimulus woodwardi Fritsch, 1899 with comparison to other highly paedomorphic belinurids

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10980
Author(s):  
Lorenzo Lustri ◽  
Lukáš Laibl ◽  
Russell D.C. Bicknell
Keyword(s):  
Horseshoe Crab ◽  
Phylogenetic Analyses ◽  
Type Specimens ◽  
Geometric Morphometric ◽  
Early Mesozoic ◽  
Late Palaeozoic ◽  
Living Fossils ◽  
Evolutionary Radiations

Xiphosurida is an ingroup of marine Euchelicerata often referred to as “living fossils”. However, this oxymoronic term is inapplicable for Paleozoic and early Mesozoic forms, as during these periods the group experienced notable evolutionary radiations; particularly the diverse late Palaeozoic clade Belinurina. Despite the iconic nature of the group, select species in this clade have been left undescribed in the light of recent geometric morphometric and phylogenetic considerations and methodologies. To this end, we re-describe Prolimulus woodwardi Fritsch, 1899 using new and type specimens to reveal more details on appendage anatomy and possible ecology. Furthermore, we present geometric morphometric and phylogenetic analyses that uncover relationships between P. woodwardi and other belinurids without genal spines. Both approaches highlight that a clade containing Prolimulus Fritsch, 1899, Liomesaspis Raymond, 1944, Alanops Racheboeuf, Vannier & Anderson, 2002 and Stilpnocephalus Selden, Simonetto & Marsiglio, 2019 may exist. While we do not erect a new group to contain these genera, we note that these genera exemplify the extreme limits of the Belinurina radiation and a peak in horseshoe crab diversity and disparity. This evidence also illustrates how changes in heterochronic timing are a key evolutionary phenomenon that can drive radiations among animals.

scholarly journals Taxonomic Re-Examination of Nine Rosellinia Types (Ascomycota, Xylariales) Stored in the Saccardo Mycological Collection

2021 ◽  
Vol 9 (3) ◽  
pp. 666
Author(s):  
Niccolò Forin ◽  
Alfredo Vizzini ◽  
Federico Fainelli ◽  
Enrico Ercole ◽  
Barbara Baldan
Keyword(s):  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Illumina Miseq ◽  
Botanical Garden ◽  
Molecular Study ◽  
Its2 Sequence ◽  
Type Specimens ◽  
Its1 Sequence ◽  
Dna Sequence Data ◽  
Nomen Novum

In a recent monograph on the genus Rosellinia, type specimens worldwide were revised and re-classified using a morphological approach. Among them, some came from Pier Andrea Saccardo’s fungarium stored in the Herbarium of the Padova Botanical Garden. In this work, we taxonomically re-examine via a morphological and molecular approach nine different Roselliniasensu Saccardo types. ITS1 and/or ITS2 sequences were successfully obtained applying Illumina MiSeq technology and phylogenetic analyses were carried out in order to elucidate their current taxonomic position. Only the ITS1 sequence was recovered for Rosellinia areolata, while for R. geophila, only the ITS2 sequence was recovered. We proposed here new combinations for Rosellinia chordicola, R. geophila and R. horridula, while for R. ambigua, R. areolata, R. australis, R. romana and R. somala, we did not suggest taxonomic changes compared to the current ones. The name Rosellinia subsimilis Sacc. is invalid, as it is a later homonym of R. subsimilis P. Karst. & Starbäck. Therefore, we introduced Coniochaeta dakotensis as a nomen novum for R. subsimilis Sacc. This is the first time that these types have been subjected to a molecular study. Our results demonstrate that old types are an important source of DNA sequence data for taxonomic re-examinations.

Reply: Evolution of central eastern Australia during the late Palaeozoic and early Mesozoic

1981 ◽  
Vol 28 (1-2) ◽  
pp. 96-97 ◽  
Author(s):  
P. R. Evans ◽  
J. Roberts
Keyword(s):  
Early Mesozoic ◽  
Late Palaeozoic ◽  
Eastern Australia ◽  
Central Eastern

Species relationships in the dasyurid marsupial genus Pseudantechinus (Marsupialia : Dasyuridae): a re-examination of the taxonomic status of Pseudantechinus roryi

2017 ◽  
Vol 65 (4) ◽  
pp. 240 ◽  
Author(s):  
L. S. Umbrello ◽  
P. A. Woolley ◽  
M. Westerman
Keyword(s):  
Dna Sequences ◽  
Isolation By Distance ◽  
Phylogenetic Analyses ◽  
Mitochondrial Gene ◽  
Taxonomic Status ◽  
Museum Collections ◽  
Species Relationships ◽  
Type Specimens ◽  
Network Analyses ◽  
The Status

The status of Pseudantechinus roryi relative to its congeners has been determined from DNA sequences obtained from both nuclear and mitochondrial gene loci. Although all other recognised species of Pseudantechinus form reciprocally monophyletic lineages in phylogenetic analyses, individuals identified in museum collections as Ps. roryi (including type specimens) were indistinguishable from those identified as Ps. macdonnellensis. Ps. roryi is thus considered to be a synonym of Ps. macdonnellensis. Neighbour-joining network analyses failed to reveal any clear biogeographic differences between populations of Ps. macdonnellensis other than some evidence of isolation by distance.

The Vietnamese population of Megophrys kuatunensis (Amphibia: Megophryidae) represents a new species of Asian horned frog from Vietnam and southern China

Zootaxa ◽  
2017 ◽  
Vol 4344 (3) ◽  
pp. 465 ◽  
Author(s):  
BENJAMIN TAPLEY ◽  
TIMOTHY CUTAJAR ◽  
STEPHEN MAHONY ◽  
CHUNG THANH NGUYEN ◽  
VINH QUANG DAU ◽  
...  
Keyword(s):  
New Species ◽  
Southern China ◽  
Phylogenetic Analyses ◽  
Eastern China ◽  
Taxonomic Status ◽  
Species Group ◽  
Type Specimens ◽  
Vietnamese Population ◽  
Group A ◽  
A New Species

The Asian frog genus Megophrys is a diverse group of morphologically conserved, forest-dwelling frogs. The genus harbours highly localised species diversification and new species continue to be described on a regular basis. We examined the taxonomic status of a population of Megophrys frogs from the Hoang Lien Range in northern Vietnam and southern China previously identified as M. kuatunensis (subgenus Panophrys). Preliminary phylogenetic analyses using a fragment of 16S rDNA places the species in question within the Megophrys (subgenus Panophrys) species group, a primarily Chinese radiation within the genus. On the basis of morphological, molecular and bioacoustic data, we conclude that this population does not represent M. kuatunensis, or any known species in the genus. We herein describe this species of Megophrys as new. Known only from Sa Pa District, Lao Cai Province in Vietnam and Jinping County, Yunnan Province in China, the new species is likely to be threatened by ongoing deforestation in the region. We provide an updated species description of M. kuatunensis based on type specimens, and suggest that M. kuatunensis is likely to be restricted to eastern China.  

Seismic imaging of Late Palaeozoic—Early Mesozoic extensional and contractional structures in the Bowen and Surat basins, eastern Australia

1992 ◽  
Vol 215 (3-4) ◽  
pp. 273-294 ◽  
Author(s):  
R.J. Korsch ◽  
K.D. Wake-Dyster ◽  
D.W. Johnstone
Keyword(s):  
Seismic Imaging ◽  
Early Mesozoic ◽  
Late Palaeozoic ◽  
Eastern Australia

scholarly journals Fungia fungites (Linnaeus, 1758) (Scleractinia, Fungiidae) is a species complex that conceals large phenotypic variation and a previously unrecognized genus

2020 ◽  
Vol 89 (2) ◽  
pp. 188-209
Author(s):  
Yutaro Oku ◽  
Kenji Iwao ◽  
Bert W. Hoeksema ◽  
Naoko Dewa ◽  
Hiroyuki Tachikawa ◽  
...  
Keyword(s):  
Species Complex ◽  
Phylogenetic Analyses ◽  
Molecular Data ◽  
Scleractinian Corals ◽  
Type Specimens ◽  
Mitochondrial Coi ◽  
Clade B ◽  
Unknown Species ◽  
Molecular Phylogenetic ◽  
Morphological Differences

Recent molecular phylogenetic analyses of scleractinian corals have resulted in the discovery of cryptic lineages. To understand species diversity in corals, these lineages need to be taxonomically defined. In the present study, we report the discovery of a distinct lineage obscured by the traditional morphological variation of Fungia fungites. This taxon exists as two distinct morphs: attached and unattached. Molecular phylogenetic analyses using mitochondrial COI and nuclear ITS markers as well as morphological comparisons were performed to clarify their phylogenetic relationships and taxonomic positions. Molecular data revealed that F. fungites consists of two genetically distinct clades (A and B). Clade A is sister to a lineage including Danafungia scruposa and Halomitra pileus, while clade B formed an independent lineage genetically distant from these three species. The two morphs were also found to be included in both clades, although the attached morph was predominantly found in clade A. Morphologically, both clades were statistically different in density of septal dentation, septal number, and septal teeth shape. These results indicate that F. fungites as presently recognized is actually a species complex including at least two species. After checking type specimens, we conclude that specimens in clade A represent true F. fungites with two morphs (unattached and attached) and that all of those in clade B represent an unknown species and genus comprising an unattached morph with only one exception. These findings suggest that more unrecognized taxa with hitherto unnoticed morphological differences can be present among scleractinian corals.

scholarly journals Completeness metrics and the quality of the sauropodomorph fossil record through geological and historical time

Paleobiology ◽  
2010 ◽  
Vol 36 (2) ◽  
pp. 283-302 ◽  
Author(s):  
Philip D. Mannion ◽  
Paul Upchurch
Keyword(s):  
Sea Level ◽  
Fossil Record ◽  
Quantitative Methods ◽  
Phylogenetic Analyses ◽  
Type Specimen ◽  
Time Interval ◽  
Historical Time ◽  
Rock Outcrop ◽  
Type Specimens ◽  
Fossil Remains

Despite increasing concerns about the effect of sampling biases on our reading of the fossil record, few studies have considered the completeness of the fossil remains themselves, and those that have tend to apply non-quantitative measures of preservation quality. Here we outline two new types of metric for quantifying the completeness of the fossil remains of taxa through time, using sauropodomorph dinosaurs as a case study. The “Skeletal Completeness Metric” divides the skeleton up into percentages based on the amount of bone for each region, whereas the “Character Completeness Metric” is based on the number of characters that can be scored for each skeletal element in phylogenetic analyses. For both metrics we calculated the completeness of the most complete individual and of the type specimen. We also calculated how well the taxon as a whole is known from its remains. We then plotted these results against both geological and historical time, and compared curves of the former with fluctuations in sauropodomorph diversity, sea level, and sedimentary rock outcrop area. Completeness through the Mesozoic shows a number of peaks and troughs; the Early Jurassic (Hettangian–Sinemurian) is the interval with highest completeness, whereas the mid-to-Late Cretaceous has completeness levels that are consistently lower than the rest of the Mesozoic. Completeness shows no relationship to rock outcrop area, but it is negatively correlated with sea level during the Jurassic–Early Cretaceous and correlated with diversity in the Cretaceous. Completeness of sauropodomorph type specimens has improved from 1830 to the present, supporting the conclusions of other recent studies. However, when this time interval is partitioned, we find no trend for an increase in completeness from the 1990s onward. Moreover, the 2000s represent one of the poorest decades in terms of average type specimen completeness. These results highlight the need for quantitative methods when assessing fossil record quality through geological time or when drawing conclusions about historical trends in the completeness of taxa. The new metrics may also prove useful as sampling proxies in diversity studies.

scholarly journals IGCP 272 - Late Palaeozoic and Early Mesozoic circum-Pacific events and their global correlation

1992 ◽  
Vol 6 ◽  
pp. 85-85
Author(s):  
J. M. Dickins
Keyword(s):  
North America ◽  
Western Europe ◽  
Important Change ◽  
Upper Permian ◽  
Triassic Boundary ◽  
Early Mesozoic ◽  
The Earth ◽  
Late Palaeozoic ◽  
Global Correlation ◽  
Harsh Climate

IGCP 203 - Permo-Triassic events of eastern Tethys and their intercontinental correlation - focussed on the Permian-Triassic boundary sequences and in particular there was a consensus that the distinctive biological changes were associated with strong sea-level and tectonic change, strong volcanic activity and a harsh climate. These factors were connected with an important change in the environment and with the exception perhaps of the climate, reflected deep-seated changes within the earth. The project also resulted in improving the physical understanding of the sequences and their biostratigraphy and correlation.IGCP 272 was developed, and was approved in 1988, to apply these results to understanding the Late Palaeozoic and Early Mesozoic and was focussed on the Pacific as integration around this region seemed to offer especially fruitful possibilities.Working group meetings up to the end of 1991 have been held in Australia (Newcastle and Hobart), New Zealand (Dunedin), South America (Sao Paulo and Buenos Aires) and North America (Washington). Meetings are planned in North America, Japan, Eastern Siberia or Thailand and western Europe (France-Spain-Austria).Special cooperation has developed with the Carboniferous, Permian and Triassic Subcommissions of IUGS and with IGCP 214 - Global Bio-events. Using the more exact time correlations developed it has now been possible to show that major geological and biological events (of different levels of significance) are associated with major boundaries already recognized in the World Standard Stratigraphical Time Scale. These comprise the Carboniferous-Permian, the mid-Permian (twofold subdivision, the Permian-Triassic (already recognized in earlier work), the Lower-Middle and Middle-Upper Triassic and the Triassic-Jurassic boundaries.A special achievement of the project has been to show the similar significance of the Midian-Dzhulfian boundary within the Upper Permian but corresponding closely to the traditional Lower-Upper Permian of China and the Middle-Upper Permian of Japan.Although there are also other events at levels which have not been investigated by the project, those outlined all seem to reflect important changes within the earth.

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