Results 11 to 20 of about 468 (168)

Xiphosura Lamsdell 2013

Palaeontology, 2012
XIPHOSURA The terminology for aspects of xiphosuran morphology largely follows Siveter & Selden (1987) and Selden & Siveter (1987). The prosoma comprises the entirety of the anterior tagma, including the dorsal carapace and the prosomal appendages. The prosomal appendages are denoted by roman numerals I–VI, appendage I being the chelicerae.
RACHEL A. MOORE, SCOTT C. McKENZIE, BRUCE S. LIEBERMAN   +2 more
core   +6 more sources

AN EFFACED HORSESHOE CRAB (ARTHROPODA: CHELICERATA: XIPHOSURA) FROM THE UPPER CARBONIFEROUS OF THE CARNIC ALPS (FRIULI, NE ITALY)

Rivista Italiana di Paleontologia e Stratigrafia, 2019
A carapace of a new horseshoe crab (Arthropoda: Chelicerata: Xiphosura) is described from the Upper Carboniferous (Kasimovian) Meledis Formation of the Carnic Alps, Friuli, Italy. It is named as Stilpnocephalus pontebbanus n. gen. & n.
PAUL A. SELDEN, LUCA SIMONETTO, GIORDANO MARSIGLIO   +2 more
doaj   +3 more sources

Wiring a periscope--ocelli, retinula axons, visual neuropils and the ancestrality of sea spiders. [PDF]

PLoS ONE, 2012
The Pycnogonida or sea spiders are cryptic, eight-legged arthropods with four median ocelli in a 'periscope' or eye tubercle. In older attempts at reconstructing phylogeny they were Arthropoda incertae sedis, but recent molecular trees placed them as the
Tobias Lehmann, Martin Hess, Roland R Melzer   +2 more
doaj   +3 more sources

Synziphosurines (Xiphosura: Chelicerata) from the Silurian of Iowa [PDF]

Journal of Paleontology, 2011
A new genus and species of synziphosurine (Chelicerata) is described from the Silurian (Wenlock) Scotch Grove Formation Konservat-Lagerstätte in Clinton County, Iowa.Camanchia grovensisn. gen. n. sp. is characterized by a sub-triangular carapace, ten opisthosomal segments divided into a preabdomen of seven and a postabdomen of three, and a tuberculate ...
Moore, R. A., Briggs, D.E.G, Braddy, SJ, Shultz, J.W   +3 more
core   +6 more sources

The diversity and evolution of chelicerate hemocyanins

BMC Evolutionary Biology, 2012
Background Oxygen transport in the hemolymph of many arthropod species is facilitated by large copper-proteins referred to as hemocyanins. Arthropod hemocyanins are hexamers or oligomers of hexamers, which are characterized by a high O2 transport ...
Rehm Peter, Pick Christian, Borner Janus, Markl Jürgen, Burmester Thorsten   +4 more
doaj   +2 more sources

Gene and Genome Duplication in Spiders. [PDF]

J Exp Zool B Mol Dev Evol
In chelicerates whole genome duplications (WGDs) were identified in distinct groups. While there is evidence that Xiphosurans/horseshoe crabs had three rounds of WGD and arachnopulmonates (e.g. spiders and scorpions) had one WGD, in many other arachnid groups no WGD was identified.
Munegowda C, Pechmann M, Prpic-Schäper NM, Turetzek N.   +3 more
europepmc   +2 more sources

Comparative studies in Chelicerata IV. Apatellata, Arachnida, Scorpionida, Xiphosura

, 1986
A comparative study is made of four chelicerate classes: Apatellata (Solifugae and Pseudoscorpionida), Arachnida s. str. (both groups of Uropygi, i.e. Holopeltida and Schizomida, Amblypygi and Araneida), Scorpionida and Xiphosura. Methods, principles and terminology, adopted in this paper, correspond with those of parts I -111 of the present series of ...
Hammen, L. van der
openaire   +2 more sources

Repeated convergent evolution of parthenogenesis in Acariformes (Acari). [PDF]

Ecol Evol, 2021
We investigated the radiation of Acariformes and reconstructed their ancestral mode of reproduction using 18S rDNA. We found that (a) Acariformes as well as Oribatida evolved from a sexual ancestor, (b) species‐rich parthenogenetic taxa radiated independently at least four times in Acariformes, (c) parthenogenesis additionally evolved frequently in ...
Pachl P, Uusitalo M, Scheu S, Schaefer I, Maraun M.   +4 more
europepmc   +2 more sources

DNA Metabarcoding Revealed Interspecific Dietary Difference and Prey Selectivity in Juvenile Horseshoe Crabs Carcinoscorpius rotundicauda and Tachypleus tridentatus From Hong Kong

Frontiers in Marine Science, 2021
Horseshoe crabs provide important ecological services including bioturbation and linking of food web in the shallow waters, but their populations are declining globally, leading to major concerns on conservation of these iconic animals.
Bo Yee Lee, Bo Yee Lee, Kaori Wakabayashi, Simon Yung Wa Sin, Susumu Ohtsuka, Ling Ming Tsang   +5 more
doaj   +1 more source

Advances in the reconstruction of the spider tree of life: A roadmap for spider systematics and comparative studies

Cladistics, Volume 39, Issue 6, Page 479-532, December 2023., 2023
Abstract In the last decade and a half, advances in genetic sequencing technologies have revolutionized systematics, transforming the field from studying morphological characters or a few genetic markers, to genomic datasets in the phylogenomic era. A plethora of molecular phylogenetic studies on many taxonomic groups have come about, converging on, or
Siddharth Kulkarni, Hannah M. Wood, Gustavo Hormiga   +2 more
wiley   +1 more source