New cyclocystoid (Phylum Echinodermata) from Anticosti Island, Quebec, and its bearing on cyclocystoid life modes

2003 ◽  
Vol 77 (5) ◽  
pp. 949-957 ◽  
Author(s):  
Alexander Glass ◽  
William I. Ausich ◽  
Paul Copper
Keyword(s):  
New Genus ◽  
Trace Fossil ◽  
Suspension Feeding ◽  
New Genus And Species ◽  
Upper Ordovician ◽  
Feeding Mode ◽  
Fossil Evidence ◽  
Anticosti Island ◽  
Bedding Surface

Nicholsodiscus anticostiensisnew genus and species (Mill Bay Member, Vauréal Formation, Rawtheyan, Upper Ordovician) is described from Anticosti Island, Quebec, Canada.Nicholsodiscus anticostiensisn. gen. and sp. is known from two complete specimens preserved in situ with the cupule-bearing side facing toward the bedding surface. Sedimentological, petrographic, and trace fossil evidence suggest that this bedding surface had the consistency of a hardground during the lifetime of the cyclocystoids. This provides the first unequivocal evidence that cyclocystoids lived with their cupule-bearing side (ventral) toward the substratum. A cupules-down orientation results in the ambulacral grooves facing the substratum. Such an orientation excludes suspension-feeding from being a possible feeding mode of the Cyclocystoidea as discussed by Henderson and Shergold (1971).A third Anticosti Island cyclocystoid specimen of unknown affinities is described from the same locality. Furthermore, a re-examination of the holotype of“Cyclocystoides” raymondiFoerste for purposes of comparison withNicholsodiscus anticostiensisn. gen. and sp. provided evidence that it is a member ofZygocycloides, albeit with missing interseptal plates.

Spiracarneyella, a new carneyellid edrioasteroid from the Upper Ordovician (Katian) of Kentucky and Ohio and comments on carneyellid heterochrony

2020 ◽  
pp. 1-6
Author(s):  
Colin D. Sumrall ◽  
Daniel Phelps
Keyword(s):  
New Genus ◽  
New Genus And Species ◽  
Upper Ordovician ◽  
The Right ◽  
Oral Area

Abstract A new genus and species of carneyellid edrioasteroid, Spiracarneyella florencei n. gen. n. sp., is described from the Upper Ordovician (Kaitian) Point Pleasant Formation of northern Kentucky and southern Ohio. Spiracarneyella n. gen. is characterized by having all five ambulacra curving clockwise around the theca, having small node-bearing interambulacral plates in the distal interambulacra, and having the periproct placement slightly offset to the right side of the CD interambulacrum. The oral area of carneyellids evolved by paedomorphosis of the oral plates covering the mouth. The straight ambulacra of Cryptogoleus and the spiraling ambulacra of Spiracarneyella n. gen. evolved by paedomorphosis and peramorphosis, respectively. UUID: http://zoobank.org/79733c8f-0bc8-4e7e-8f77-8508f576755c

scholarly journals Polymorphy and extinction of the Late Cretaceous burrowing shrimp Protocallianassa faujasi and first record of the genera Corallianassa and Calliax (Crustacea, Decapoda, Thalassinoidea) from the Cretaceous

2001 ◽  
Vol 70 (2) ◽  
pp. 85-98 ◽  
Author(s):  
Krista Swen ◽  
René H.B. Fraaije ◽  
Gijsbert J. van der Zwaan
Keyword(s):  
New Species ◽  
First Record ◽  
Suspension Feeding ◽  
Feeding Mode ◽  
Male And Female ◽  
Immature Male ◽  
Type Area ◽  
Mode Of Life ◽  
Burrow Morphology

A biometric study of chelae of the burrowing shrimp Protocallianassa faujasi ( Desmarest, 1822), from the late Maastrichtian of the Maastrichtian type area, The Netherlands, has revealed three morphotypes. These types are interpreted as sexual dimorphs (male and female) and earliest ecdysis stages (immature male). Among the studied material are fifteen specimens of a new Cretaceous callianassid, Corallianassa acucurvata new species, one specimen provisionally assigned to the genus Calliax and a callianassid from the Danian. Burrows preserving callianassid chelae in situ are discussed. Based on burrow morphology a suspension feeding mode of life for P.faujasi is inferred, whereas C. acucurvata n. sp. probably was an active omnivorous analogue of its closest Recent relatives. The extinction of P. faujasi in the Meerssen Member appears to correspond to the increase in seagrass vegetation. The Protocallianassa-Corallianassa faunal changeover took place about 100,000 yrs before the K/T boundary in this region.

scholarly journals A new ankylosaurine dinosaur from the Judith River Formation of Montana, USA, based on an exceptional skeleton with soft tissue preservation

2017 ◽  
Vol 4 (5) ◽  
pp. 161086 ◽  
Author(s):  
Victoria M. Arbour ◽  
David C. Evans
Keyword(s):  
Soft Tissue ◽  
North America ◽  
New Genus ◽  
Rapid Evolution ◽  
Tissue Preservation ◽  
New Genus And Species ◽  
Soft Tissue Preservation ◽  
Judith River Formation ◽  
Stratigraphic Succession

The terrestrial Judith River Formation of northern Montana was deposited over an approximately 4 Myr interval during the Campanian (Late Cretaceous). Despite having been prospected and collected continuously by palaeontologists for over a century, few relatively complete dinosaur skeletons have been recovered from this unit to date. Here we describe a new genus and species of ankylosaurine dinosaur, Zuul crurivastator , from the Coal Ridge Member of the Judith River Formation, based on an exceptionally complete and well-preserved skeleton (ROM 75860). This is the first ankylosaurin skeleton known with a complete skull and tail club, and it is the most complete ankylosaurid ever found in North America. The presence of abundant soft tissue preservation across the skeleton, including in situ osteoderms, skin impressions and dark films that probably represent preserved keratin, make this exceptional skeleton an important reference for understanding the evolution of dermal and epidermal structures in this clade. Phylogenetic analysis recovers Zuul as an ankylosaurin ankylosaurid within a clade of Dyoplosaurus and Scolosaurus , with Euoplocephalus being more distantly related within Ankylosaurini. The occurrence of Z. crurivastator from the upper Judith River Formation fills a gap in the ankylosaurine stratigraphic and geographical record in North America, and further highlights that Campanian ankylosaurines were undergoing rapid evolution and stratigraphic succession of taxa as observed for Laramidian ceratopsids, hadrosaurids, pachycephalosaurids and tyrannosaurids.

Stoibocephalum n. gen. (Cestoda: Lecanicephalidea) from the sharkray, Rhina ancylostoma Bloch & Schneider (Elasmobranchii: Rhinopristiformes), from northern Australia

Zootaxa ◽  
2013 ◽  
Vol 3626 (4) ◽  
pp. 558-568 ◽  
Author(s):  
JOANNA J. CIELOCHA ◽  
KIRSTEN JENSEN
Keyword(s):  
Intestinal Mucosa ◽  
New Genus ◽  
Apical Organ ◽  
Northern Australia ◽  
New Genus And Species ◽  
The Third ◽  
Histological Sections ◽  
Egg Morphology

A new genus and species of lecanicephalidean cestode, Stoibocephalum arafurense n. gen., n. sp., is described from the sharkray, Rhina ancylostoma Bloch & Schneider, off northern Australia. Stoibocephalum arafurense n. gen., n. sp. Is apolytic, and possesses a large, muscular, retractable apical organ, 3 pairs of excretory vessels, and testes in several columns and layers. The presence of 3 pairs of excretory vessels distinguishes this new genus from all other valid lecanicephalidean genera, except Hexacanalis Perrenoud, 1931, from which it can be distinguished based on ovary shape and egg morphology. Stoibocephalum n. gen. most closely resembles Tylocephalum Linton, 1890 but differs from that genus in its ability to completely retract its apical organ into the scolex proper. Scolex microthrix pattern and histological sections of scoleces attached in situ suggest S. arafurense n. gen., n. sp. to attach to the host’s intestinal mucosa with apical organ and scolex proper surfaces, rather than just the apical organ surface. This is the third lecanicephalidean species described from the sharkray.

Solving the mystery of crinoid ancestry: new fossil evidence of arm origin and development

2009 ◽  
Vol 83 (3) ◽  
pp. 350-364 ◽  
Author(s):  
Thomas E. Guensburg ◽  
James Sprinkle
Keyword(s):  
New Genus ◽  
First Record ◽  
New Genus And Species ◽  
Early Ordovician ◽  
New Family ◽  
Fossil Evidence

Apektocrinus ubaghsinew genus and species is a monospecific taxon assigned to the new family Apektocrinidae based on additional preparation of a single previously studied specimen.Apektocrinusis among the oldest known crinoids (Early Tremadoc, Early Ordovician). Although expressing crinoid apomorphies, it is interpreted as retaining plesiomorphies in its arms reflecting early edrioasteroid rather than blastozoan (eocrinoid) ancestry. Apomorphies represent basal crinoid and cladid (crownward) levels of phylogeny.Restudy fortifies previous reports of the presence of a basal echinoderm plesiomorphy; floor plates above brachials in the arms ofApektocrinus, as well as in other approximately contemporary crinoids.Apektocrinusfurnishes the first record of podial basins in crinoid arms. Arms and calyx ofApektocrinusmerge gradually, facilitated by continuations of interbrachials (extraxial body plates) extending onto the arms and separating floor plates from brachials. These arm interbrachials, which diminish and pinch out distally as floor plates nestle into the brachial (adoral) groove, have not been recognized as such in crinoids.

scholarly journals Enigmatic amphibians in mid-Cretaceous amber were chameleon-like ballistic feeders

Science ◽  
2020 ◽  
Vol 370 (6517) ◽  
pp. 687-691 ◽  
Author(s):  
Juan D. Daza ◽  
Edward L. Stanley ◽  
Arnau Bolet ◽  
Aaron M. Bauer ◽  
J. Salvador Arias ◽  
...  
Keyword(s):  
New Genus ◽  
Soft Tissues ◽  
Three Dimensional ◽  
New Genus And Species ◽  
Feeding Mode

Albanerpetontids are tiny, enigmatic fossil amphibians with a distinctive suite of characteristics, including scales and specialized jaw and neck joints. Here we describe a new genus and species of albanerpetontid, represented by fully articulated and three-dimensional specimens preserved in amber. These specimens preserve skeletal and soft tissues, including an elongated median hyoid element, the tip of which remains embedded in a distal tongue pad. This arrangement is very similar to the long, rapidly projecting tongue of chameleons. Our results thus suggest that albanerpetontids were sit-and-wait ballistic tongue feeders, extending the record of this specialized feeding mode by around 100 million years.

Enigmatic fossil encrusting an Upper Ordovician rocky shore on Hudson Bay, Canada

1998 ◽  
Vol 72 (5) ◽  
pp. 927-932 ◽  
Author(s):  
Markes E. Johnson ◽  
Mu Xi-Nan ◽  
Rong Jia-Yu
Keyword(s):  
Green Algae ◽  
Colony Size ◽  
Rocky Shore ◽  
New Genus ◽  
Transverse Section ◽  
Longitudinal Section ◽  
Hudson Bay ◽  
New Genus And Species ◽  
Upper Ordovician ◽  
Maximum Thickness

Storeacolumnella hudsonensis is described as a new genus and species of encrusting, colonial organism that lived in an intertidal, rocky-shore environment. The fossil was discovered in the basal beds of the Upper Ordovician Port Nelson Formation at a coastal outcrop on Hudson Bay near Churchill, Manitoba. Showing some possible characteristics of sponges and other possible characteristics of calcaerous green algae, this matlike organism is considered nonetheless to have uncertain taxonomic affinities. It consists of cylinder-shaped columns, each with an internal system of star-shaped filaments or spicules as viewed in transverse section. The cylinders stand vertical in longitudinal section and are densely packed together to form a mat. The hard substrate to which the mat is attached consists of a boulder eroded from the Precambrian Churchill Quartzite. Maximum colony size observed in a single example exhibits a diameter of not less than 80 mm and maximum thickness of 5.85 mm.

Description and correlation of Late Ordovician conodonts from the D. ornatus and P. pacificus graptolite zones, Road River Group, northern Yukon Territory

1987 ◽  
Vol 24 (7) ◽  
pp. 1450-1464 ◽  
Author(s):  
Alexander D. McCracken
Keyword(s):  
New Species ◽  
New Genus ◽  
Late Ordovician ◽  
Yukon Territory ◽  
Upper Ordovician ◽  
The Road ◽  
Anticosti Island ◽  
Blackstone River ◽  
A New Species

Upper Ordovician carbonate beds within clastic strata of the Road River Group, northern Yukon Territory, have yielded 403 conodont elements representing 25 species; 19 of these are illustrated. Genera present are Amorphognathus, Belodina, Besselodus, Drepanoistodus, Eocarniodus?, Gamachignathus, Icriodella, Noixodontus, Oulodus, Panderodus s.l., Paroistodus?, Plectodina, Protopanderodus, Pseudobelodina s.l., Scabbardella, Strachanognathus, and Walliserodus. The apparatus of new genus A new species A includes a symmetrical and bifurrowed rastrate element.Sparse conodont faunas from Rock River occur in strata below a level bearing graptolites of the D. ornatus Zone and between this zone and the succeeding P. pacificus Zone. These conodonts have a range of "Trentonian" –Gamachian (upper Caradoc –Hirnantian).The fauna from Blackstone River is from a single bed that is 3 m below the G. persculptus Zone? and 13.7 m above the P. pacificus Zone. Although stratigraphically closer to the former, this fauna may be equivalent to a level within the P. pacificus Zone; the conodonts suggest correlation with the late Richmondian Fauna 12 and the lower G. ensifer Zone of Anticosti Island, Quebec. A similar fauna (G. ensifer Zone) occurs in one horizon within the P. pacificus Zone at upper Peel River. One metre above this is the informal D. cf. D. mirus graptolite biohorizon (P. pacificus Zone).The Blackstone and Peel faunas equate to a level within the Ordovician Anceps bands C and D of the Ordovician–Silurian boundary stratotype at Dob's Linn, Scotland. The interval of Fauna 13 and the Gamachian Stage may correspond to Anceps Band E and the C.? extraordinarius Band (and contiguous strata) at Dob's Linn. The base of the G. ensifer Zone and the higher base of the Gamachian are probably late Rawtheyan.

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