The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Bhart-anjan S. Bhullar - One of the best experts on this subject based on the ideXlab platform.
-
a tiny triassic saurian from connecticut and the early evolution of the diapsid Feeding Apparatus
Nature Communications, 2018Co-Authors: Adam C Pritchard, Gabriel S Bever, Jacques A Gauthier, Michael Hanson, Bhart-anjan S. BhullarAbstract:Following the Permo–Triassic Extinction, large-bodied diapsid reptiles—with a body length >1 m—rapidly expanded their ecological roles. This diversification is reflected in enormous disparity in the development of the rostrum and adductor chamber. However, it is unclear how marked the diversity of the Feeding Apparatus was in contemporary small-bodied diapsids. Here we describe the remarkably small skull (2.5 cm long) of a saurian reptile, Colobops noviportensis, gen. et sp. nov., from the Triassic New Haven Arkose of Connecticut, USA. The taxon possesses an exceptionally reinforced snout and strikingly expanded supratemporal fossae for adductor musculature relative to any known Mesozoic or Recent diapsid of similar size. Our phylogenetic analyses support C. noviportensis as an early diverging pan-archosaur. Colobops noviportensis reveals extraordinary disparity of the Feeding Apparatus in small-bodied early Mesozoic diapsids, and a suite of morphologies, functionally related to a powerful bite, unknown in any small-bodied diapsid. The Triassic fossil record is biased towards large species, obscuring the anatomical diversity of small species. Here, the authors describe a new species, Colobops noviportensis, based on a 2.5 cm-long skull with proportionally large attachments for jaw muscles, expanding the known diversity of early diapsids.
-
A tiny Triassic saurian from Connecticut and the early evolution of the diapsid Feeding Apparatus.
Nature Communications, 2018Co-Authors: Adam C Pritchard, Gabriel S Bever, Jacques A Gauthier, Michael Hanson, Bhart-anjan S. BhullarAbstract:Following the Permo-Triassic Extinction, large-bodied diapsid reptiles-with a body length >1 m-rapidly expanded their ecological roles. This diversification is reflected in enormous disparity in the development of the rostrum and adductor chamber. However, it is unclear how marked the diversity of the Feeding Apparatus was in contemporary small-bodied diapsids. Here we describe the remarkably small skull (2.5 cm long) of a saurian reptile, Colobops noviportensis, gen. et sp. nov., from the Triassic New Haven Arkose of Connecticut, USA. The taxon possesses an exceptionally reinforced snout and strikingly expanded supratemporal fossae for adductor musculature relative to any known Mesozoic or Recent diapsid of similar size. Our phylogenetic analyses support C. noviportensis as an early diverging pan-archosaur. Colobops noviportensis reveals extraordinary disparity of the Feeding Apparatus in small-bodied early Mesozoic diapsids, and a suite of morphologies, functionally related to a powerful bite, unknown in any small-bodied diapsid.
Richard E Triemer - One of the best experts on this subject based on the ideXlab platform.
-
Character evolution in heterotrophic euglenids
European Journal of Protistology, 2001Co-Authors: Brian S Leander, Richard E Triemer, Mark A FarmerAbstract:This article attempts to describe the key morphological innovations associated with the evolutionary transitions between bacteriotrophy, eukaryotrophy, phototrophy, and osmotrophy in euglenids. Attention was focused on heterotrophic euglenids in an effort to establish a robust phylogenetic hypothesis for the group as a whole. We present a cladistic analysis of a large morphological data set from the following taxa: Petalomonas, Entosiphon, Lentomonas, Ploeotia, Dinema, Distigma, Rhabdomonas, Menoidium, Peranema, Urceolus, Eutreptia, and Euglena. The majority of the 37 characters and 97 states recognized were associated with the pellicle, the Feeding Apparatus, and the flagellar Apparatus. In addition to having pellicle strips, Petalomonas cantuscygni possessed mitochondrial inclusions that were strikingly similar to the kinetoplasts found in kinetoplastids. Dinema sulcatum held a pivotal position in the phylogenetic tree and possessed many characters that bridged bacteriotrophic taxa with eukaryotrophic taxa. Distigmids and rhabdomonads formed a clade of osmotrophs that descended from eukaryotrophic ancestors, while Urceolus cyclostomus possessed a Feeding Apparatus, a putative photoreception Apparatus and cytoskeletal features that clearly linked the phototrophs to eukaryotrophic ancestors. Evolutionary implications that emerged from these results were discussed.
-
RECONSTRUCTION OF THE Feeding Apparatus IN PLOEOTIA COSTATA (EUGLENOPHYTA) AND ITS RELATIONSHIP TO OTHER EUGLENOID Feeding ApparatusES
Journal of Phycology, 1999Co-Authors: Eric W. Linton, Richard E TriemerAbstract:The ultrastructure of the Feeding Apparatus in Ploeotia costata Farmer and Triemer was determined and compared to other euglenoid Feeding Apparatuses. The Feeding Apparatus opened subapically onto the ventral surface and extended nearly the entire length of the cell. It consisted of four parts at the anterior surface: a comb, cytostome/pocket, vanes, and supporting rods. The comb was a multilayered structure of three horizontal microtubular rows encased in cement and formed the dorsal lip of the Apparatus. The cytostome/pocket was located between the comb and the supporting rods, tapered into the cell as the cytopharynx and was surrounded by five vanes. The electron-opaque vanes extended the entire length of the Feeding Apparatus and were lined with microtubules for most of their length. Finally, two cement supporting rods that were joined by a crosspiece at the anterior end formed the ventral lip. The rods separated briefly before merging with the vanes. As the merged rods and vanes descended into the cell, they gradually narrowed and terminated. Comparisons of the Feeding Apparatus with Ploeotia vitrea, Diplonema ambulator, Lentomonas applanatum, and other euglenoids have led to the conclusion that the Type II Feeding Apparatus is found only in Ploeotia species.
-
Feeding IN PERANEMA TRICHOPHORUM REVISITED (EUGLENOPHYTA)1
Journal of Phycology, 1997Co-Authors: Richard E TriemerAbstract:Feeding in Peranema trichophorum (Ehrenberg 1838) Stein 1878 was first observed over a century ago, yet there is still contention over how the Feeding Apparatus is used in Feeding. Using video microscopy and scanning microscopy, this study documents two types of Feeding. Peranema may engulf prey cells whole. Immotile cells are preferred, but moving cells occasionally are engulfed. Details of the early stages of engulfment are presented using scanning electron microscopy. A second method of Feeding begins with the attachment of Peranema to a prey cell. The rods of the Feeding Apparatus then are repeatedly scraped over the surface of the prey until a tear occurs in the cell. The Feeding Apparatus is inserted into the opening and the internal cell contents are sucked out. The anterior flagellum is inserted into the prey to help remove the cell's contents.
-
an ultrastructural study of lentomonas applanatum preisig n g euglenida
Journal of Eukaryotic Microbiology, 1994Co-Authors: Mark A Farmer, Richard E TriemerAbstract:. Lentomonas applanatum (syn. Entosiphon applanatum Preisig) is a biflagellate, phagotrophic euglenid found in intertidal salt marshes. Lentomonas applanatum bears a superficial similarity to Entosiphon sulcatum, however, an ultrastructural study of L. applanatum revealed many features that are atypical for other described species of the genus Entosiphon. These features include number and organization of pellicular strips, construction of the Feeding Apparatus, nature of the flagellar transition zone and flagellar Apparatus, and point of flagellar emergence. These differences show that L. applanatum is related more closely to phagotrophic genera such as Ploeotia than to E. sulcatum. The construction of the Feeding Apparatus and pellicle suggest that L. applanatum has retained many of the pleisiomorphic characters that were present in the earliest euglenids. The presence of similar structures in other related protists may provide important clues as to the evolution of the Euglenida.
-
An ultrastructural comparison of the mitotic Apparatus, Feeding Apparatus, flagellar Apparatus and cytoskeleton in euglenoids and kinetoplastids
Protoplasma, 1991Co-Authors: Richard E Triemer, M. A. FarmerAbstract:The euglenoids and kinetoplastids form a diverse assemblage of organisms which show no obvious phylogenetic relationship with other flagellates. An ultrastructural examination and comparison of the flagellar Apparatus, the Feeding Apparatus, and mitotic nucleus indicate a number of shared morphological features which support a common ancestry for the two groups. Of particular interest is the euglenoid,Petalomonas cantuscygni, which shares many of the ultrastructural features common to both groups. Based on the data presented, we hypothesize that a euglenoid with features similar to those now present inP. cantuscygni was ancestral to both the euglenoid and kinetoplastid lines.
Jacques A Gauthier - One of the best experts on this subject based on the ideXlab platform.
-
a tiny triassic saurian from connecticut and the early evolution of the diapsid Feeding Apparatus
Nature Communications, 2018Co-Authors: Adam C Pritchard, Gabriel S Bever, Jacques A Gauthier, Michael Hanson, Bhart-anjan S. BhullarAbstract:Following the Permo–Triassic Extinction, large-bodied diapsid reptiles—with a body length >1 m—rapidly expanded their ecological roles. This diversification is reflected in enormous disparity in the development of the rostrum and adductor chamber. However, it is unclear how marked the diversity of the Feeding Apparatus was in contemporary small-bodied diapsids. Here we describe the remarkably small skull (2.5 cm long) of a saurian reptile, Colobops noviportensis, gen. et sp. nov., from the Triassic New Haven Arkose of Connecticut, USA. The taxon possesses an exceptionally reinforced snout and strikingly expanded supratemporal fossae for adductor musculature relative to any known Mesozoic or Recent diapsid of similar size. Our phylogenetic analyses support C. noviportensis as an early diverging pan-archosaur. Colobops noviportensis reveals extraordinary disparity of the Feeding Apparatus in small-bodied early Mesozoic diapsids, and a suite of morphologies, functionally related to a powerful bite, unknown in any small-bodied diapsid. The Triassic fossil record is biased towards large species, obscuring the anatomical diversity of small species. Here, the authors describe a new species, Colobops noviportensis, based on a 2.5 cm-long skull with proportionally large attachments for jaw muscles, expanding the known diversity of early diapsids.
-
A tiny Triassic saurian from Connecticut and the early evolution of the diapsid Feeding Apparatus.
Nature Communications, 2018Co-Authors: Adam C Pritchard, Gabriel S Bever, Jacques A Gauthier, Michael Hanson, Bhart-anjan S. BhullarAbstract:Following the Permo-Triassic Extinction, large-bodied diapsid reptiles-with a body length >1 m-rapidly expanded their ecological roles. This diversification is reflected in enormous disparity in the development of the rostrum and adductor chamber. However, it is unclear how marked the diversity of the Feeding Apparatus was in contemporary small-bodied diapsids. Here we describe the remarkably small skull (2.5 cm long) of a saurian reptile, Colobops noviportensis, gen. et sp. nov., from the Triassic New Haven Arkose of Connecticut, USA. The taxon possesses an exceptionally reinforced snout and strikingly expanded supratemporal fossae for adductor musculature relative to any known Mesozoic or Recent diapsid of similar size. Our phylogenetic analyses support C. noviportensis as an early diverging pan-archosaur. Colobops noviportensis reveals extraordinary disparity of the Feeding Apparatus in small-bodied early Mesozoic diapsids, and a suite of morphologies, functionally related to a powerful bite, unknown in any small-bodied diapsid.
Adam C Pritchard - One of the best experts on this subject based on the ideXlab platform.
-
a tiny triassic saurian from connecticut and the early evolution of the diapsid Feeding Apparatus
Nature Communications, 2018Co-Authors: Adam C Pritchard, Gabriel S Bever, Jacques A Gauthier, Michael Hanson, Bhart-anjan S. BhullarAbstract:Following the Permo–Triassic Extinction, large-bodied diapsid reptiles—with a body length >1 m—rapidly expanded their ecological roles. This diversification is reflected in enormous disparity in the development of the rostrum and adductor chamber. However, it is unclear how marked the diversity of the Feeding Apparatus was in contemporary small-bodied diapsids. Here we describe the remarkably small skull (2.5 cm long) of a saurian reptile, Colobops noviportensis, gen. et sp. nov., from the Triassic New Haven Arkose of Connecticut, USA. The taxon possesses an exceptionally reinforced snout and strikingly expanded supratemporal fossae for adductor musculature relative to any known Mesozoic or Recent diapsid of similar size. Our phylogenetic analyses support C. noviportensis as an early diverging pan-archosaur. Colobops noviportensis reveals extraordinary disparity of the Feeding Apparatus in small-bodied early Mesozoic diapsids, and a suite of morphologies, functionally related to a powerful bite, unknown in any small-bodied diapsid. The Triassic fossil record is biased towards large species, obscuring the anatomical diversity of small species. Here, the authors describe a new species, Colobops noviportensis, based on a 2.5 cm-long skull with proportionally large attachments for jaw muscles, expanding the known diversity of early diapsids.
-
A tiny Triassic saurian from Connecticut and the early evolution of the diapsid Feeding Apparatus.
Nature Communications, 2018Co-Authors: Adam C Pritchard, Gabriel S Bever, Jacques A Gauthier, Michael Hanson, Bhart-anjan S. BhullarAbstract:Following the Permo-Triassic Extinction, large-bodied diapsid reptiles-with a body length >1 m-rapidly expanded their ecological roles. This diversification is reflected in enormous disparity in the development of the rostrum and adductor chamber. However, it is unclear how marked the diversity of the Feeding Apparatus was in contemporary small-bodied diapsids. Here we describe the remarkably small skull (2.5 cm long) of a saurian reptile, Colobops noviportensis, gen. et sp. nov., from the Triassic New Haven Arkose of Connecticut, USA. The taxon possesses an exceptionally reinforced snout and strikingly expanded supratemporal fossae for adductor musculature relative to any known Mesozoic or Recent diapsid of similar size. Our phylogenetic analyses support C. noviportensis as an early diverging pan-archosaur. Colobops noviportensis reveals extraordinary disparity of the Feeding Apparatus in small-bodied early Mesozoic diapsids, and a suite of morphologies, functionally related to a powerful bite, unknown in any small-bodied diapsid.
Gabriel S Bever - One of the best experts on this subject based on the ideXlab platform.
-
a tiny triassic saurian from connecticut and the early evolution of the diapsid Feeding Apparatus
Nature Communications, 2018Co-Authors: Adam C Pritchard, Gabriel S Bever, Jacques A Gauthier, Michael Hanson, Bhart-anjan S. BhullarAbstract:Following the Permo–Triassic Extinction, large-bodied diapsid reptiles—with a body length >1 m—rapidly expanded their ecological roles. This diversification is reflected in enormous disparity in the development of the rostrum and adductor chamber. However, it is unclear how marked the diversity of the Feeding Apparatus was in contemporary small-bodied diapsids. Here we describe the remarkably small skull (2.5 cm long) of a saurian reptile, Colobops noviportensis, gen. et sp. nov., from the Triassic New Haven Arkose of Connecticut, USA. The taxon possesses an exceptionally reinforced snout and strikingly expanded supratemporal fossae for adductor musculature relative to any known Mesozoic or Recent diapsid of similar size. Our phylogenetic analyses support C. noviportensis as an early diverging pan-archosaur. Colobops noviportensis reveals extraordinary disparity of the Feeding Apparatus in small-bodied early Mesozoic diapsids, and a suite of morphologies, functionally related to a powerful bite, unknown in any small-bodied diapsid. The Triassic fossil record is biased towards large species, obscuring the anatomical diversity of small species. Here, the authors describe a new species, Colobops noviportensis, based on a 2.5 cm-long skull with proportionally large attachments for jaw muscles, expanding the known diversity of early diapsids.
-
A tiny Triassic saurian from Connecticut and the early evolution of the diapsid Feeding Apparatus.
Nature Communications, 2018Co-Authors: Adam C Pritchard, Gabriel S Bever, Jacques A Gauthier, Michael Hanson, Bhart-anjan S. BhullarAbstract:Following the Permo-Triassic Extinction, large-bodied diapsid reptiles-with a body length >1 m-rapidly expanded their ecological roles. This diversification is reflected in enormous disparity in the development of the rostrum and adductor chamber. However, it is unclear how marked the diversity of the Feeding Apparatus was in contemporary small-bodied diapsids. Here we describe the remarkably small skull (2.5 cm long) of a saurian reptile, Colobops noviportensis, gen. et sp. nov., from the Triassic New Haven Arkose of Connecticut, USA. The taxon possesses an exceptionally reinforced snout and strikingly expanded supratemporal fossae for adductor musculature relative to any known Mesozoic or Recent diapsid of similar size. Our phylogenetic analyses support C. noviportensis as an early diverging pan-archosaur. Colobops noviportensis reveals extraordinary disparity of the Feeding Apparatus in small-bodied early Mesozoic diapsids, and a suite of morphologies, functionally related to a powerful bite, unknown in any small-bodied diapsid.
