The Systematic Position ofPseudomicrothorax dubius, Ciliate with a Unique Combination of Anatomical Features*

Stegocoleus Jarzembowski & Wang is an enigmatic genus in the family Ommatidae, known to date only from Burmese amber. This genus possesses a unique combination of characters, including antennal grooves on the ventral side of head, well-developed epipleural rims, and presence of separated procoxae, which makes its systematic position unclear. Here we report two new species of Lepidomma from mid-Cretaceous Burmese amber, L. longisquama sp. nov. and L. jarzembowskii sp. nov. Based on these well-preserved specimens and new morphological details revealed by widefield fluorescence and confocal microscopy, we discuss the morphological similarities between Lepidomma and the enigmatic Stegocoleus. We suggest that Stegocoleus is not a basal ommatid, but a highly derived form of ommatid beetles.

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Stem anatomy in the spiny american palm Bactris (Arecaceae-Bactridinae)

Hoehnea ◽

10.1590/2236-8906-18/2015 ◽

2015 ◽

Vol 42 (3) ◽

pp. 567-579 ◽

Cited By ~ 1

Author(s):

Tracy Monique Magellan ◽

P. Barry Tomlinson ◽

Brett A. Huggett

Keyword(s):

Cell Expansion ◽

Systematic Position ◽

Small Sample ◽

Wall Thickening ◽

Stem Anatomy ◽

Anatomical Features ◽

Fiber Wall ◽

American Palm ◽

Generic Groups ◽

Developmental Features

ABSTRACT Bactris trunks are made entirely by long sustained primary growth so that mechanical properties develop progressively as the trunk matures. Anatomical features vary throughout the stem so that one small sample is a limited representation. This limits the use for stem histology with systematic purposes. We examined stem anatomy in 17 out of 73 species representing all major sub-generic groups. Stem features do not associate well with the subdivision of the genus. Distinctive structural and developmental features: are the presence of fiber strands independent of the vascular tissues, the modified ground parenchyma with a late formation of air-lacunae, and the early inception of the mechanically significant outer central cylinder. Cell expansion and fiber wall thickening develop as the stem ages, but vary in their expression in stems of different diameter. Our example thus provides an explanation for the difficulty of identifying the systematic position of fossil palm stems.

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Over-splitting destabilizes the taxonomy of hylaranine frogs: A response to Chandramouli et al. (2020)

Zootaxa ◽

10.11646/zootaxa.4877.3.11 ◽

2020 ◽

Vol 4877 (3) ◽

pp. 598-600

Author(s):

KIN ONN CHAN ◽

ROBIN K. ABRAHAM ◽

MARITES B. SANGUILA ◽

RAFE M. BROWN

Keyword(s):

16S Rrna ◽

Genetic Divergence ◽

Lithophyllum species from Brazilian coast: range extension of Lithophyllum margaritae and description of Lithophyllum atlanticum sp. nov. (Corallinales, Corallinophycidae, Rhodophyta)

Phytotaxa ◽

10.11646/phytotaxa.190.1.21 ◽

2014 ◽

Vol 190 (1) ◽

pp. 355 ◽

Cited By ~ 5

Author(s):

Talita Vieira-Pinto ◽

Mariana C. Oliveira ◽

Janayna Bouzon ◽

Marina Sissini ◽

Joseph L. Richards ◽

...

Keyword(s):

Dna Sequences ◽

Cell Walls ◽

Molecular Data ◽

Systematic Position ◽

Coralline Algae ◽

Brazilian Coast ◽

Coast Range ◽

Southern Brazil ◽

Anatomical Studies ◽

Anatomical Features

Coralline algae (Corallinophycidae, Rhodophyta) are primarily characterized by the impregnation of calcium carbonate (calcite) in their cell walls. To determine the systematic position of genera and species, researchers are increasingly combining anatomical studies with comparisons of DNA sequences. In the present study we have described the main representatives of the genus Lithophyllum in intertidal and subtidal habitats from the southern coast of Brazil based on anatomical studies, supported by molecular markers. Analyses were conducted on specimens collected from five sites along the coast of southern Brazil. Anatomical studies were carried out by light and scanning electron microscopy. Molecular studies were based on DNA barcoding markers (cox1; UPA) and SSU rDNA. Using comparative anatomical features, corroborated by the molecular data, we identified two taxonomic entities from the Brazilian coast: Lithophyllum margaritae, and we propose the new species Lithophyllum atlanticum.

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A new radiodontan oral cone with a unique combination of anatomical features from the early Cambrian Guanshan Lagerstätte, eastern Yunnan, South China

Journal of Paleontology ◽

10.1017/jpa.2017.77 ◽

2017 ◽

Vol 92 (1) ◽

pp. 40-48 ◽

Cited By ~ 6

Author(s):

Han Zeng ◽

Fangchen Zhao ◽

Zongjun Yin ◽

Maoyan Zhu

Keyword(s):

South China ◽

Mouth Opening ◽

Body Parts ◽

Unique Combination ◽

Feeding Behaviors ◽

Future Studies ◽

Anatomical Features ◽

Oral Cone ◽

Stage 4 ◽

New Knowledge

AbstractThe radiodontans, including anomalocaridids and their allies, are enigmatic stem-group euarthropods and are the most ancient apex giant predators known from the fossil record. Most studies on their feeding behaviors have emphasized their diverse and abundant raptorial frontal appendages, while the oral cone surrounding the mouth opening in these animals has attracted less attention. At present, three oral cone morphotypes are known, from Anomalocaris Whiteaves, 1892, Peytoia Walcott, 1911, and Hurdia Walcott, 1912, respectively. In this paper, we report on a novel form of radiodontan oral cone from the Guanshan Lagerstätte (Cambrian Series 2, Stage 4) in the Wulongqing Formation, eastern Yunnan, South China. This oral cone is unique in combining features seen in Peytoia/Hurdia and Anomalocaris. It possesses a Peytoia/Hurdia-type ‘tetraradial’ configuration comprising a 32-plate outer ring that consists of four perpendicularly arranged large plates and 28 small plates, in addition to furrowed folds and scale-like nodes on plate surfaces otherwise seen only in Anomalocaris. As an intermediate morphotype, the Guanshan oral cone improves our understanding of the occurrence and morphological disparity of radiodontan oral cones, illuminates future investigations on potentially variable radiodontan feeding mechanisms, and reveals possible evolutionary transformations of these peculiar feeding structures. The resolution of current radiodontan phylogeny would be potentially improved by new knowledge on other body parts apart from frontal appendages in future studies.

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Cones, needles and wood: Micraspis (Micraspidaceae, Micraspidales fam. et ord. nov.) speciation segregates by host plant tissues

Fungal Systematics and Evolution ◽

10.3114/fuse.2020.05.05 ◽

2020 ◽

Vol 5 (1) ◽

pp. 99-112 ◽

Cited By ~ 1

Author(s):

L. Quijada ◽

J.B. Tanney ◽

E. Popov ◽

P.R. Johnston ◽

D.H. Pfister

Keyword(s):

Host Plant ◽

Northern Hemisphere ◽

Picea Mariana ◽

Molecular Data ◽

Systematic Position ◽

Host Tissue ◽

Plant Tissues ◽

Unique Combination ◽

Unique Type ◽

New Family

Micraspis acicola was described more than 50 years ago to accommodate a phacidium-like fungus that caused a foliar disease of Picea mariana. After its publication, two more species were added, M. strobilina and M. tetraspora, all of them growing on Pinaceae in the Northern Hemisphere, but each species occupying a unique type of host tissue (needles, cones or wood). Micraspis is considered to be a member of class Leotiomycetes, but was originally placed in Phacidiaceae (Phacidiales), later transferred to Helotiaceae (Helotiales) and recently returned to Phacidiales but in a different family (Tympanidaceae). The genus remains poorly sampled, and hence poorly understood both taxonomically and ecologically. Here, we use morphology, cultures and sequences to provide insights into its systematic position in Leotiomycetes and its ecology. Our results show that the genus should not be included in Tympanidaceae or Phacidiaceae, and support the erection of a new family and order with a unique combination of morphological features supported by molecular data.

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Cranial Anatomical Integration and Disparity Among Bones Discriminate Between Primates and Non-primate Mammals

Evolutionary Biology ◽

10.1007/s11692-021-09555-9 ◽

2021 ◽

Author(s):

Borja Esteve-Altava

Keyword(s):

Network Analysis ◽

Brain Size ◽

Late Development ◽

Unique Combination ◽

Anatomical Features ◽

True Effect ◽

Open Question ◽

Anatomical Network Analysis

AbstractThe primate skull hosts a unique combination of anatomical features among mammals, such as a short face, wide orbits, and big braincase. Together with a trend to fuse bones in late development, these features define the anatomical organization of the skull of primates—which bones articulate to each other and the pattern this creates. Here, I quantified the anatomical organization of the skull of 17 primates and 15 non-primate mammals using anatomical network analysis to assess how the skulls of primates have diverged from those of other mammals, and whether their anatomical differences coevolved with brain size. Results show that primates have a greater anatomical integration of their skulls and a greater disparity among bones than other non-primate mammals. Brain size seems to contribute in part to this difference, but its true effect could not be conclusively proven. This supports the hypothesis that primates have a distinct anatomical organization of the skull, but whether this is related to their larger brains remains an open question.

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A remarkable new species of Hypogastrura (Collembola, Hypogastruridae) from the Romanian Carpathians

Zootaxa ◽

10.11646/zootaxa.5067.3.7 ◽

2021 ◽

Vol 5067 (3) ◽

pp. 439-446

Author(s):

GRZEGORZ PAŚNIK ◽

JAKUB STERNALSKI

Keyword(s):

New Species ◽

Antennal Segment ◽

Morphological Characters ◽

Systematic Position ◽

Morphological Features ◽

Present System ◽

Unique Combination ◽

Romanian Carpathians ◽

A New Species

A new species of Hypogastrura from the Romanian Carpathians is described and illustrated. The new species is characterised by unique combination of morphological characters: presence of seven ocelli, the antennal segment IV with 4 thin, cylindrical sensilla, the presence of 5 setae on ventral tube, the short anal spines situated on high papillae and distinct chaetotaxy. The species is not easy to classify in the present system of the generic subdivision. Considering the presence of only 7+7 ocelli, the new species can be compared only with H. pyrenaica (Cassagnau, 1959), while in other morphological features it is similar to H. aterrima Yosii, 1972 and H. tethyca Ellis, 1976. The similarity between these species and systematic position of the new species are discussed.

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The anatomy and systematic position of the theropod dinosaurChilantaisaurus tashuikouensisHu, 1964 from the Early Cretaceous of Alanshan, People's Republic of China

Geological Magazine ◽

10.1017/s0016756808005475 ◽

2008 ◽

Vol 145 (6) ◽

pp. 778-789 ◽

Cited By ~ 31

Author(s):

ROGER B. J. BENSON ◽

XU XING

Keyword(s):

Upper Cretaceous ◽

Phylogenetic Analyses ◽

Distal Humerus ◽

Systematic Position ◽

Theropod Dinosaur ◽

Anatomical Features ◽

Republic Of China ◽

Tibial Length ◽

Basal Position

AbstractThere is little consensus on the systematic position of the colossal theropod dinosaurChilantaisaurus tashuikouensisfrom the Cretaceous (Aptian–?Albian or Upper Cretaceous) Ulansuhai Formation of Inner Mongolia, which has been recovered as a derived member of both Allosauroidea and Spinosauroidea by numerical phylogenetic analyses. Redescription of the type material ofC. tashuikouensisreveals an unusual combination of morphological features that render determination of its systematic position problematic. It possesses anatomical features that have been proposed as synapomorphies of Neotetanurae: a preacetabular fossa on the ilium, and a wedge-shaped cross-section of the shaft of the third metatarsal. It also shares some features with specific allosauroid taxa: a pronounced ulnar epicondyle on the humerus, and a prominent medial shelf bounding the preacetabular fossa on the ilium (also present in tyrannosauroids). However, it lacks some features that are present in all other allosauroids: a marked depression on the anterior surface of the distal humerus adjacent to the ulnar condyle, and a humerus that is less than 0.4 times the length of the femur; it furthermore possesses a tibial astragalar facet that is approximately 10% of the tibial length, which suggests a more basal position within Tetanurae.Chilantaisaurusshares certain features with some spinosauroids: an enlarged and elongated first manual ungual, and a suprastragalar buttress that has been modified to a vertical ridge, but these characters are not unique to spinosauroids. A highly reduced fourth trochanter may be an autapomorphy ofChilantaisaurus, as has previously been suggested, or unite the taxon with Coelurosauria in an entirely novel grouping. On the basis of these observations it is likely thatChilantaisaurusis a neotetanuran, but unlikely that it is an allosauroid.Chilantaisaurusmay belong to an alternative lineage of very large theropods that continued into the Cretaceous from the diversification of basal neotetanurans during the Middle Jurassic.

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The systematic position of Pulchrinodus inflatus (Pterobryaceae, Bryopsida) based on molecular data. Studies in austral temperate rainforest bryophytes 21

Australian Systematic Botany ◽

10.1071/sb02022 ◽

2003 ◽

Vol 16 (5) ◽

pp. 561 ◽

Cited By ~ 14

Author(s):

M. Stech ◽

D. Quandt ◽

A. Lindlar ◽

J.-P. Frahm

Keyword(s):

Maximum Likelihood ◽

Molecular Level ◽

Molecular Data ◽

Systematic Position ◽

Unique Combination ◽

Sterile Condition ◽

Close Relationship ◽

Systematic Relationships ◽

First Time ◽

Molecular Trees

The systematic position of the rare moss Pulchrinodus inflatus (Hook. f. & Wils.) Allen, which is only known in sterile condition, has so far been dubious. The species has been transferred between very distant families of the Bryopsida, such as the haplolepideous Dicnemonaceae (Dicranales) or the diplolepideous Pterobryaceae (Leucodontales). To clarify the systematic relationships of Pulchrinodus at the molecular level, three DNA regions, the cpDNA trnL–F and psbT–H regions and the nrDNA ITS2, were sequenced. The psbT–H region is employed for the first time in the Bryopsida. In maximum parsimony and maximum likelihood trees, Pulchrinodus is clearly separated from the genera Dicnemon, Eucamptodon and Mesotus of Dicnemonaceae. Furthermore, a close relationship to genera of the Pterobryaceae (Hildebrandtiella, Pterobryon) is also not indicated. The molecular data, therefore, contradict a position of Pulchrinodus either in the haplolepideous mosses or in the Hypnales (today including the Leucodontales). Instead, the placement of Pulchrinodus in the molecular trees, near to species of the Rhizogoniaceae and Orthotrichaceae, together with its unique combination of gametophytic characters, indicates that Pulchrinodus occupies an isolated position in a grade diverging early within the diplolepideous mosses.

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