scholarly journals A soft-bodied lophophorate from the Silurian of England

2010 ◽  
Vol 7 (1) ◽  
pp. 146-149 ◽  
Author(s):  
M. D. Sutton ◽  
D. E. G. Briggs ◽  
David J. Siveter ◽  
Derek J. Siveter
Keyword(s):  
The Body ◽  
Molecular Evidence ◽  
Ventral Valve ◽  
Dorsal Valve ◽  
Significant Element ◽  
Stem Group

Soft-bodied taxa comprise an important component of the extant lophophorate fauna, but convincing fossils of soft-bodied lophophorates are extremely rare. A small fossil lophophorate, attached to a brachiopod dorsal valve, is described from the Silurian (Wenlock Series) Herefordshire Lagerstätte of England. This unmineralized organism was bilaterally symmetrical and comprised a subconical body attached basally to the host and partially enclosed by a broad ‘hood’; the body bore a small, coiled lophophore. Where the hood attached laterally, there is a series of transverse ridges and furrows. The affinities of this organism probably lie with Brachiopoda; the hood is interpreted as the homologue of a dorsal valve/mantle lobe, and the attachment as the homologue of the ventral valve and/or pedicle. The ridges are arranged in a manner that suggests constructional serial repetition, indicating that they are unlikely to represent mantle canals. Extant brachiopods are not serially structured, but morphological and molecular evidence suggests that their ancestors were. The new organism may belong to the brachiopod stem group, and might also represent a significant element of the Palaeozoic lophophorate fauna.

Review of some Perinereis Kinberg, 1865 (Annelida: Nereididae) species of Group 2 sensu Hutchings, Reid & Wilson, 1991 from the Eastern and South-eastern Asian seas

2021 ◽  
pp. 1-29
Author(s):  
Tulio F. Villalobos-Guerrero ◽  
Taeseo Park ◽  
Izwandy Idris
Keyword(s):  
Morphological Analysis ◽  
Species Group ◽  
The Body ◽  
Valid Species ◽  
Molecular Evidence ◽  
South Eastern ◽  
Generic Position ◽  
Perinereis Aibuhitensis ◽  
Group 2 ◽  
Pharyngeal Area

Abstract The present study reviews Perinereis Group 2 species from the Eastern and South-eastern Asian seas based on morphological analysis of the types, non-types and original descriptions, and the use of molecular evidence (COI and 16S rDNA) from newly collected material. These species are characterized by having two bar-shaped paragnaths on pharyngeal area VI, which are often deemed conical when small and pointed, triggering misidentifications as to Neanthes species. New terminology and definition for this particular type of bars are proposed, and the generic position of some resembling Neanthes species is also re-assessed. Five species are transferred to Perinereis: Perinereis babuzai comb. nov., P. belawanensis comb. nov., P. kinmenensis comb. nov., P. shigungensis comb. nov. and P. vitabunda comb. nov. ‘Perinereis aibuhitensis’ species group is newly proposed by encompassing species having proximal dorsal ligule similar throughout the body, dorsal cirri short, and blades of heterogomph falcigers straight with long terminal tooth forming a distinct tendon. Perinereis belawanensis comb. nov., P. linea and P. vitabunda comb. nov. are redescribed. Perinereis linea is regarded as a senior synonym of Nereis (Neanthes) orientalis and Perinereis vancaurica tetradentata based on type material, whereas its exotic status in the Mediterranean Sea is questioned. An identification key to all currently valid species within Perinereis Group 2 is also provided.

scholarly journals Schizocrania (Brachiopoda, Discinoidea): taxonomy, occurrence, ecology and history of the earliest epizoan lingulate brachiopod

2016 ◽  
Vol 72 (3-4) ◽  
pp. 225-238 ◽  
Author(s):  
Michal Mergl ◽  
Lucie Nolčová
Keyword(s):  
Trophic Structure ◽  
Ventral Valve ◽  
Dorsal Valve ◽  
Early Devonian ◽  
Sea Floor ◽  
Open Sea ◽  
History Of ◽  
Barrandian Area ◽  
Floating Objects ◽  
First Time

The lingulate brachiopod Schizocrania (Trematidae, Discinoidea) is reviewed. Ptychopeltis is definitively synonymized with Schizocrania, because new data indicate that convexity of the shell, profile of the anterior margin commissure, density of the dorsal valve costellation, ornamentation of the ventral valve and shape of the pedicle notch are worthless for separation of these genera. Four Ordovician species of Schizocrania are reported from the Barrandian area: S. multistriata (Darriwilian), S. hornyi (Sandbian), S. incola (Sandbian) and the new species S. equestra sp. nov. (Katian). Occurrence of Schizocrania striata is confirmed for the first time around the S/D boundary in the Barrandian area. Schizocrania has a wide geographic range with mid-Ordovician to early Devonian occurrences in Laurentia, Avalonia, West Gondwana and the Silurian occurrence in Baltica. Schizocrania was the earliest lingulate brachiopod adhering to floating objects in an open sea (both living cephalopods and their empty drifting shells), but it was highly opportunistic, and used any vacant hard surface on the sea floor (conulariids, strophomenid brachiopods, trilobites) as a suitable substrate for settlement of the larva. Decline of the genus coincided with disappearance of planktic graptolites, and might have been caused by competition of rapidly evolving planktic dacryoconarids, increased predation pressure, and rebuilding of the trophic structure in the early Devonian seas.

Rare primitive deuterostomes from the Cambrian (Series 3) of Utah

2015 ◽  
Vol 89 (4) ◽  
pp. 631-636 ◽  
Author(s):  
Simon Conway Morris ◽  
Susan L. Halgedahl ◽  
Paul Selden ◽  
Richard D. Jarrard
Keyword(s):  
New Species ◽  
Fossil Record ◽  
Type Species ◽  
The Body ◽  
New Taxon ◽  
Burgess Shale ◽  
Anterior Section ◽  
Stem Group ◽  
Stratigraphic Range ◽  
New Discovery

AbstractThe fossil record of early deuterostome history largely depends on soft-bodied material that is generally rare and often of controversial status. Banffiids and vetulicystids exemplify these problems. From the Cambrian (Series 3) of Utah, we describe specimens of Banffia episoma n. sp. (from the Spence Shale) and Thylacocercus ignota n. gen. n. sp. (from the Wheeler Formation). The new species of Banffia Walcott, 1911 shows significant differences to the type species (B. constricta Walcott, 1911) from the Cambrian (Series 3, Stage 5) Burgess Shale, notably in possessing a prominent posterior unit but diminished anterior section. Not only does this point to a greater diversity of form among the banffiids, but also B. episoma indicates that the diagnostic median constriction and crossover of either side of the body are unlikely to be the result of taphonomic twisting but are original features. Comparisons extend also to the Cambrian (Series 2) Heteromorphus Luo and Hu in Luo et al., 1999 and, collectively, these observations support an assignment of the banffiids to the vetulicolians. The new taxon T. ignota represents the first discovery of a vetulicystid from beyond China and also significantly extends its stratigraphic range from Series 2 Cambrian into Series 3 Cambrian. Despite overall similarities in bodyplan, T. ignota differs from other vetulicystids in a number of respects, notably the possession of an anterior zone with broad tentacle-like structures. This new discovery is consistent with the vetulicystids representing stem-group ambulacrarians.

On New Brachiopoda, and on the Development of the Loop in Terebratella

The Geologist ◽  
1861 ◽  
Vol 4 (3) ◽  
pp. 96-99 ◽  
Author(s):  
Charles Moore
Keyword(s):  
Ventral Valve ◽  
Dorsal Valve ◽  
Longitudinal Groove ◽  
Considerable Portion ◽  
Longitudinal Septum

Shell inequivalve; punctuate, rather rugose, front deep, rounded; attached by a considerable portion of the ventral valve; beak slightly incurved; deltidium small and depressed. The ventral valve is flattened on its under side. Its interior is surrounded by an elevated, slightly granulated margin. Under the deltidium are seen two raised oval processes, separated by a longitudinal septum, which occupies the greater length of the shell. The exterior of the dorsal valve is rugose and flattened. The interior possesses a narrow, thin, punctuated margin, immediately succeeding which is a ridge of single granulations, which are stronger towards the frontal margin, gradually disappearing as the ridge passes upwards. Springing from the centre of this granulated ridge is a septum, slightly tapering from its base, on either side strongly serrated, between which is a central longitudinal groove. The septum occupies nearly the whole height allowed by the cavity of the shell, and divides it to nearly three-fourths of its length. From the top of the septum there are thrown off two extremely delicate lamellæ, forming a loop which curves downwards towards the front of the shell, where they bifurcate, and are then again united to the shell at its inner sides. Above the septum and attached lamellæ a band occurs, forming a bridge over the visceral cavity. This is united to the granulated ridge, which thus completely surrounds the inner portion of the valve.

A new species and southernmost record of Cestrus Townes (Hymenoptera, Ichneumonidae, Cryptinae)

Zootaxa ◽  
2020 ◽  
Vol 4822 (2) ◽  
pp. 277-284
Author(s):  
FERNANDA A. SUPELETO ◽  
BERNARDO F. SANTOS ◽  
ALEXANDRE P. AGUIAR
Keyword(s):  
New Species ◽  
Atlantic Forest ◽  
Rare Species ◽  
First Record ◽  
The Body ◽  
Dorsal Valve ◽  
Brazilian Atlantic Forest ◽  
Apical Margin ◽  
Yellow Stripe ◽  
A New Species

Cestrus itatiensis sp. nov., from the Brazilian Atlantic Forest, is described and illustrated. This is the southernmost record for the genus and the first record in Brazil. The new species is characterized by having the body reddish brown; a narrow yellow stripe along eye margin on supra-clypeal area, reaching briefly the supra-antennal area; transverse carina of propodeum complete and stout; postpetiole and T2–8 progressively dark brown towards apical margin in a somewhat triangular pattern; and apex of dorsal valve of ovipositor with nine distinct teeth. Extensive sampling suggest this is a rare species. 

scholarly journals Four new species of troglomorphic Coecobrya Yosii, 1956 (Collembola, Entomobryidae) from Thailand based on morphological and molecular evidence, with an updated key of Thai troglomorphic species

2021 ◽  
Vol 41 ◽  
pp. 1-42
Author(s):  
Areeruk Nilsai ◽  
Matsapume Detcharoen ◽  
Nerivania Nunes Godeiro ◽  
Sopark Jantarit
Keyword(s):  
New Species ◽  
Large Body ◽  
Nuclear Gene ◽  
The Body ◽  
Valid Species ◽  
Species Discrimination ◽  
Molecular Evidence ◽  
Orange Pigment ◽  
Unique Character ◽  
Dichotomous Key

Four new species of troglomorphic Coecobrya Yosii, 1956 are described from caves located in the central and northeastern regions of Thailand. Coecobrya whittenisp. nov. and C. troglobiasp. nov. are from Khon Kaen province, C. ellisisp. nov. is from Phetchabun province and C. phitsanulokensissp. nov. is from Phitsanulok province. They all exhibit remarkable troglobitic characters i.e. elongated antennae, legs and furca, slender claw complex and large body size. Coecobrya whittenisp. nov. is similar to C. troglobiasp. nov. and they were found a distance of only 3.4 km from each other. However, they are mainly different in the number of An mac on dorsal head and number of chaetae of Th. II. Likewise, C. ellisisp. nov. is similar to C. phitsanulokensissp. nov.. However, they differ in the number of An mac on the dorsal head, the number of central mac on Abd. II, central mac on Abd. IV, lateral mac on Abd. IV and the number of inner teeth of the claw. Moreover, C. ellisisp. nov. has orange pigment dots on the body, a unique character, considering that all other troglomorphic Coecobrya species in Thailand are devoid of pigmentation. The results of the molecular approach based on two partial mitochondrial markers (COI and 16S rDNA) and a nuclear gene fragment (28S rDNA) supported the results of morphological species discrimination in separating the four nominal populations as valid species. An updated dichotomous key of Thai troglomorphic Coecobrya species is also given.

scholarly journals A possible case of inverted lifestyle in a new bivalved arthropod from the Burgess Shale

2019 ◽  
Vol 6 (11) ◽  
pp. 191350 ◽  
Author(s):  
Alejandro Izquierdo-López ◽  
Jean-Bernard Caron
Keyword(s):  
Phylogenetic Analysis ◽  
National Park ◽  
Suspension Feeder ◽  
The Body ◽  
Burgess Shale ◽  
Middle Cambrian ◽  
Bayesian Phylogenetic Analysis ◽  
Stem Group ◽  
Potential Case ◽  
Caudal Rami

The origin of the arthropod carapace, an enlargement of cephalic tergites, can be traced back to the Cambrian period. However, its disparity and evolution are still not fully understood. Here, we describe a new ‘bivalved’ arthropod, Fibulacaris nereidis gen. et sp. nov., based on 102 specimens from the middle Cambrian (Wuliuan Stage) Burgess Shale, Marble Canyon area in British Columbia's Kootenay National Park, Canada. The laterally compressed carapace covers most of the body. It is fused dorsally and merges anteriorly into a conspicuous postero-ventrally recurved rostrum as long as the carapace and positioned between a pair of backwards-facing pedunculate eyes. The body is homonomous, with approximately 40 weakly sclerotized segments bearing biramous legs with elongate endopods, and ends in a pair of small flap-like caudal rami. Fibulacaris nereidis is interpreted as a suspension feeder possibly swimming inverted, in a potential case of convergence with some branchiopods. A Bayesian phylogenetic analysis places it within a group closely related to the extinct Hymenocarina. Fibulacaris nereidis is unique in its carapace morphology and overall widens the ecological disparity of Cambrian arthropods and suggests that the evolution of a ‘bivalved' carapace and an upside-down lifestyle may have occurred early in stem-group crustaceans.

Taxonomic revision of Aegla lata Bond-Buckup & Buckup, 1994 (Decapoda: Anomura: Aeglidae), with the description of a new species of Aegla Leach, 1820 from the Upper Paraná Ecoregion, Brazil

2020 ◽  
Vol 40 (4) ◽  
pp. 425-434
Author(s):  
Ingrid C Marçal ◽  
Fernanda P Páez ◽  
Lenice Souza-Shibatta ◽  
Silvia H Sofia ◽  
Gustavo M Teixeira
Keyword(s):  
New Species ◽  
River Basin ◽  
Taxonomic Revision ◽  
Morphological Characters ◽  
The Body ◽  
Type Locality ◽  
Morphological Data ◽  
Molecular Evidence ◽  
Coi Mtdna ◽  
A New Species

Abstract Aegla lata Bond-Buckup & Buckup, 1994 is considered extinct in the type locality. New populations of this species, however, have been found in northern Paraná state, Brazil. We revised the taxonomy of A. lata based on morphological data obtained from the type material and specimens recently obtained from streams of the Tibagi River sub-basin, Paranapanema River basin, Upper Paraná Ecoregion. Moreover, Aegla jacutingan. sp. is described and illustrated. The new species resembles A. lata in the shapes of the body and chelipeds. Both species are nevertheless separated by particular morphological characters of the carapace, chelipeds, and epimeron as well as by molecular (COI mtDNA) differences. Both species can be distinguished from their congeners based on morphological and molecular evidence.

scholarly journals V.—On the Denticulated Structure of the Hinge–line of Spirifera trigonalis, Martin

1884 ◽  
Vol 1 (1) ◽  
pp. 18-20 ◽  
Author(s):  
John Young
Keyword(s):  
Outer Edge ◽  
Ventral Valve ◽  
Dorsal Valve ◽  
Hinge Line ◽  
Lower Carboniferous ◽  
Fossiliferous Limestone ◽  
The Way

Recently, when examining some weathered fossiliferous limestone shale from the Lower Carboniferous strata of East Kilbride, Lanarkshire, my attention was attracted to some fragments of the valves of Spirifera trigonalis, Martin, in which I noticed, on the hinge-line of the dorsal valve, a row of small, round, hollow pits, and on the hinge-line of the ventral valve, a corresponding row of small, projecting, rounded denticles. These characters I had not noticed before, and on searching further, I found other fragments of the valves showing the same thing. This led to an examination of more perfect specimens of this Spirifera, contained in my own collection, and that of Dr. J. R. S. Hunter, of Braidwood, Carluke, and in one example, where the valves had slightly opened through pressure, on clearing away the shale, I found, on the outer edge of the ventral valve, a distinct row of small projecting denticles, that had evidently fitted into hollow pits or sockets in the dorsal valve, but from the way the valves had shifted in this specimen these were not seen. These denticles, when looked at externally, are nearly as numerous, and much of the same size, as those seen in many of the hinge-lines of shells of the genus Area, only in this genus, the teeth are the same in each valve, and lock into each other.

Molecular evidence for the role of a ferric reductase in iron transport

2002 ◽  
Vol 30 (4) ◽  
pp. 722-724 ◽  
Author(s):  
A. T. McKie ◽  
G. O. Latunde-Dada ◽  
S. Miret ◽  
J. A. McGregor ◽  
G. J. Anderson ◽  
...  
Keyword(s):  
Reductase Activity ◽  
The Body ◽  
Molecular Evidence ◽  
Ferric Reductase ◽  
Divalent Metal Transporter 1 ◽  
Divalent Metal Transporter ◽  
Metal Transporter ◽  
Cytochrome B561 ◽  
Haem Protein

Duodenal cytochrome b (Dcytb) is a haem protein similar to the cytochrome b561 protein family. Dcytb is highly expressed in duodenal brush-border membrane and is implicated in dietary iron absorption by reducing dietary ferric iron to the ferrous form for transport via Nramp2/DCT1 (divalent-cation transporter 1)/DMT1 (divalent metal-transporter 1). The protein is expressed in other tissues and may account for ferric reductase activity at other sites in the body.

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