[Paleontology • 2024] Akrophyllas gen. nov. • Elongate Ediacaran fronds from the Flinders Ranges, South Australia

 Akrophyllas longa (Glaessner & Wade, 1966)

in Grimes, Narbonne, Gehling, Trusler et Dececchi, 2024

DOI: doi.org/10.1017/jpa.2023.45

Abstract

Decimeter-scale, elongate, fossil fronds from the Ediacara Range in South Australia were formally described as Rangea longa Glaessner and Wade, 1966, but the disparate nature of documented specimens has hindered their inclusion in global syntheses and has resulted in these fossils being assigned to at least five different genera in two different clades since their discovery. Detailed study of the type material from the Ediacara Range and the few specimens subsequently collected elsewhere in the Flinders Ranges reaffirms that these specimens represent a single species, with the apparent morphological variation between specimens entirely taphonomic and reflecting the obverse and reverse surfaces of these fronds coupled with the orientation of the frond axis and petaloids at different angles relative to the sea bottom on which they were preserved. The preserved architecture of these fronds constitutes three orders of branching microstructure that are strictly orthogonal to immediately higher and lower orders. This implies affinities with the arboreomorphs, but representing a new frond genus herein named Akrophyllas. Akrophyllas n. gen. differs from all other Ediacaran fronds in exhibiting a stalk that is visible only on one side of the frond and is internal to the other side where the first-order branches instead meet at a zigzag axial trace. Akrophyllas n. gen. was attached to a bulbous holdfast on the sea bottom, and evidence for current scours that formed in the lee of the fronds and for a strong current alignment of felled fronds with depositional overlap of adjacent fronds imply an upright, epibenthic lifestyle for Akrophyllas longa new combination.

Taphonomic variation in preservation of  Akrophyllas longa n., comb. on bedding surfaces.
 (1) SAM P24593, the largest-known specimen of Akrophyllas n. gen., preserved in part and counterpart as a cleavage relief within a thick bed of laminated sandstone from Nilpena, with preservation of the marginal rim (mr), central stalk (cs), and two orders of branching (br) through composite molding.
(2) SAM P12716 showing preservation of current-aligned and locally overlapping specimens of Akrophyllas n. gen. on an epirelief (top) surface in the Mincham-Flounders collection from Ediacara Range. Fronds (A) and (B) preserved in reverse view; frond (D) preserved in obverse view. Frond (B) partly overlies (A); frond (D) partly overlies (C), which may represent a separate frond, ...

Systematic paleontology

Clade Arboreomorpha

Genus Akrophyllas new genus

Type species: Rangea longa Glaessner and Wade, 1966 

Diagnosis: New. Elongate, gently tapering, bifoliate petalodium attached to a discoid to spheroidal holdfast via a short stem or a naked stalk. Petalodium architecture consisting of three orders of strictly orthogonal branching, with mm-scale, second-order rectangular branches at right angles to the first-order branches and submillimetric third-order rectangular branches at right ...

Etymology: Akros meaning “at the top” in Greek, in reference to its unusual preservation on the tops of sandstone beds. Phyllas meaning “leaf” in Greek, in reference to the overall lanceolate to linear, leaf-like shape of its petalodium. In combination with its original species name “longa”, it is the “long leaf at the top”.

Remarks: This material previously has been referred to at least five different genera in two different major groupings of Ediacaran fronds. Its architecture indicates that it is an arboreomorph whose construction differs from all previously described fronds.

  Morphological reconstruction of Akrophyllas longa n., comb. (1) Complete erect frond attached to the sea bottom. The twist midway through the frond is diagrammatic to show both sides of the frond. (2) Close-up of the obverse side of the frond, which shows the first-order branches passing off a prominent central stalk. (3) Close-up of the reverse side of the frond, which shows the first-order branches meeting at a zigzag axial trace running the length of the frond.

 

Kelsey F. Grimes, Guy M. Narbonne, James G. Gehling, Peter W. Trusler and T. Alexander Dececchi. 2024. Elongate Ediacaran fronds from the Flinders Ranges, South Australia. Journal of Paleontology. 98(2); 249 - 265. DOI: doi.org/10.1017/jpa.2023.45

[Paleontology • 2024] Douglassarachne acanthopoda • A remarkable Spiny Arachnid (Arachnida: Pantetrapulmonata) from the Pennsylvanian Mazon Creek Lagerstätte, Illinois

 Douglassarachne acanthopoda 

 Selden & Dunlop, 2024

 

DOI: 10.1017/jpa.2024.13 

 

Abstract

A new genus and species of arachnid (Chelicerata: Arachnida), Douglassarachne acanthopoda n. gen. n. sp., is described from the late Carboniferous (Moscovian) Coal Measures of the Mazon Creek Lagerstätte, Illinois, USA. This is a unique animal with distinctive large spines on the legs. It has a subovate body, a segmented opisthosoma, and a terminal anal tubercle. The legs are robust and appear to have been similar in construction throughout the limb series, with heavy spination of the preserved proximal podomeres. The mouthparts and coxo-sternal region are equivocal. The preserved character combination does not permit easy referral to any known arachnid order, living or extinct, thus the new fossil in placed as Arachnida/Pantetrapulmonata incertae sedis. It contributes to an emerging pattern of disparate body plans among late Carboniferous arachnids, ranging from anatomically modern members of living orders through to extinct taxa, such as the present fossil, whose phylogenetic position remains unresolved.

 Douglassarachne acanthopoda n. gen. n. sp., holotype and only known specimen FMNH PE 91366.
 (1) Photograph of part; (2) explanatory drawing of part; (3) photograph of counterpart; (4) explanatory drawing of counterpart; 1–4 = leg numbers; a t = anal tubercle; e t = eye tubercle; fe = femur; t = tergite. Scale bars = 5 mm.

 Douglassarachne acanthopoda n. gen. n. sp., reconstruction of the possible appearance of the animal in life.

Systematic paleontology

Class Arachnida Lamarck, Reference Lamarck, 1801

Pantetrapulmonata incertae sedis

Genus Douglassarachne new genus

Type species: Douglassarachne acanthopoda new species, by monotypy.

 

The genus is named for the Douglass family who kindly donated the specimen to the Field Museum for study.

 

Douglassarachne acanthopoda new species

Diagnosis: Relatively large arachnid (body length >15 mm) with median dorsal ocular tubercle on carapace, abdominal tergites, anal tubercle, legs bearing many long, curved macrospines.

Etymology: From the Greek αγκάθι, a thorn or prickle, and πόδι, leg, with reference to the very spiny legs of this animal.

Paul A. Selden and Jason A. Dunlop. 2024. A remarkable Spiny Arachnid from the Pennsylvanian Mazon Creek Lagerstätte, Illinois. Journal of Paleontology. DOI: doi.org/10.1017/jpa.2024.13 

Non-technical Summary: The forests of the late Carboniferous period (about 300–320 million years ago) harbored a great variety of arachnids. In addition to the familiar spiders, harvestmen, and scorpions, there were other, stranger kinds of spider-like animals. Here, we describe a large spider-like arachnid with very spiny legs (presumably to deter predators), from the world-famous Mazon Creek fossil localities of Illinois, USA.

[Paleontology • 2024] Stenokranio boldi • A New eryopid temnospondyl (Temnospondyli: Eryopidae) from the Carboniferous–Permian Boundary of Germany

  

Stenokranio boldi

 Werneburg, Witzmann, Rinehart, Fischer & Voigt, 2024

DOI: 10.1017/jpa.2023.58

Abstract

A new eryopid temnospondyl, Stenokranio boldi n. gen. n. sp. is described based on well-preserved cranial and postcranial material from fluvio-lacustrine deposits of the Permo-Carboniferous (Gzhelian/Asselian) Remigiusberg Formation at the Remigiusberg quarry near Kusel, Saar–Nahe Basin, southwest Germany. The new taxon is characterized by three autapomorphies within the Eryopidae: (1) the relatively narrow posterior skull table, therefore nearly parallel lateral margins of the skull; (2) the short postparietals and tabulars; and (3) the wide ectopterygoid. Phylogenetic analysis reveals a monophyletic Eryopidae with the basal taxa Osteophorus, Glaukerpeton, and Onchiodon labyrinthicus forming a polytomy. Actinodon may be either a basal eryopid or a stereospondylomorph, and the genus Onchiodon is not monophyletic. Stenokranio n. gen. is found as a more derived eryopid forming the sister taxon to Eryops. Stenokranio n. gen. was among the largest predators of the Saar–Nahe Basin. Its semiaquatic lifestyle enabled Stenokranio n. gen. to browse riverbanks and lake shorelines for prey, but most likely it fed on aquatic vertebrates. Stenokranio n. gen. was part of a faunal assemblage of aquatic, semiaquatic, and fully terrestrial vertebrates, such as sarcopterygian and actinopterygian fishes, xenacanthid sharks, a dvinosaurian temnospondyl, different “lepospondyls”, diadectomorphs, and synapsids. This is in general accordance with the vertebrate community from the Permo-Carboniferous of North America and from the early Permian localities of Manebach (Thuringian Forest Basin) and Niederhäslich (Döhlen Basin). It is notable that the occurrence of Stenokranio n. gen. and other eryopids in these localities excluded the presence of other large temnospondyls such as Sclerocephalus. However, a previously described isolated eryopid mandible from the Remigiusberg locality differs from that of Stenokranio n. gen. in several characters, implying that probably two different eryopid taxa lived at the same locality.

 

Stenokranio boldi n. gen. n. sp., skull with mandibles and anterior postcranial skeleton, paratype NHMMZ/LS PW 2019/5022.
Dorsal skull roof with left mandible, shoulder girdle, and anterior axial skeleton

Systematic paleontology

Tetrapoda Jaekel, 1909

Amphibia Linneaus, 1758

Temnospondyli von Zittel, 1888

Eryopidae Cope, 1882

Stenokranio new genus

 

Etymology: Greek στενός (stenos) for narrow, κρανίο (kranio) for skull.

Stenokranio boldi new species

Etymology: The species name honors the late Rudolf Bold from Rammelsbach near Kusel who found the holotype and only known specimen of the Remigiusberg sphenacodontid Cryptovenator hirschbergeri Fröbisch et al., 2011, in 2002.

 

Ralf Werneburg, Florian Witzmann, Larry Rinehart, Jan Fischer and Sebastian Voigt. 2024. A New eryopid temnospondyl from the Carboniferous–Permian Boundary of Germany. Journal of Paleontology. FirstView. pp. 1 - 31. DOI: 10.1017/jpa.2023.58

[Paleontology • 2023] Mobulavermis adustus • A large pelagic lobopodian from the Cambrian Pioche Shale of Nevada, USA

Mobulavermis adustus

 McCall, 2023

DOI: 10.1017/jpa.2023.63 

 twitter.com/Prehistorica_CM

Abstract

Lobopodians are an iconic and diverse group of animals from the Cambrian, which alongside radiodonts, present an important window into the evolution of arthropods and the development of Paleozoic ecosystems. Of these, a rare few species outside of Radiodonta possess lateral swimming flaps. The recent discovery of Utahnax provided much-needed insight into the evolution of swimming flaps, suggesting that the ventrolateral flaps of Kerygmachela evolved independently from other flap-bearing lobopodians and radiodonts. Here a new pelagic lobopodian species is described, Mobulavermis adustus new genus new species, the first lobopodian to be reported from the Cambrian-age Pioche Shale of Nevada. Mobulavermis adustus was large and possessed more ventrolateral flap pairs than any other known lobopodian or radiodont. It is found to be a close relative of both Kerygmachela and Utahnax, allowing the establishment of the new lobopodian family Kerygmachelidae new family. In addition, an indeterminate euarthropod fossil from the Pioche Formation is described in brief, and the recently described Chengjiang species Parvibellus avatus Liu et al., 2022, thought to have been related to the “gilled lobopodians,” is reinterpreted as a juvenile siberiid lobopodian.

 

Mobulavermis adustus KUMIP 298510 (holotype) from the Pioche Shale, middle Cambrian, Nevada:
(1) KUMIP 298510a (part), immersed, showing curving body and caudal spine preserved in negative relief; (2) KUMIP 298510b (counterpart), immersed, with caudal spine in strong positive relief; (3) KUMIP 298510b (counterpart), dry, closeup of caudal spine in positive relief and some reduced terminal flaps; (4) KUMIP 298510a (part), immersed, closeup of trunk interior, showing digestive tract, possible gut gland, and possible evidence of strong trunk annulation; (5) KUMIP 298510b (counterpart), dry, closeup of flap surfaces near anterior of specimen.

Scale bars = 10 mm. afm = anterior flap margin; an = annulations; bw = body wall; cs = caudal spine; dt = digestive tract; fo = flap ornamentation; mg = midgut gland; pfm = posterior flap margin; tf = terminal reduced flaps.

Systematic paleontology

Superphylum Panarthropoda Nielsen, Reference Nielsen1995

Family Kerygmachelidae new family

Type genus: Kerygmachela Budd, 1993.

Other taxa included: Utahnax Lerosey-Aubril and Ortega-Hernández, 2022, Mobulavermis n. gen.

Diagnosis: Lobopodians with lobopod-derived ventrolateral swimming flaps and lacking dorsal flaps or setal blades; trunk elongate, roughly cylindrical, and annulated; paired frontal appendages large and raptorial.

Genus Mobulavermis new genus

Type species: Mobulavermis adustus, by monotypy.

Etymology: From Mobula, the genus name of extant manta rays and devil rays, drawing comparison to the elongate flexible caudal spines and broad swimming flaps of Mobula rays, which resemble the outline of the new taxon, combined with the Latin vermis, meaning “worm.”

Mobulavermis adustus new species 

Anomalocaridid gen. indet. sp. indet.; Lieberman, 2003; p. 683, fig. 6.4.

indeterminate anomalocaridid; Lerosey-Aubril and Ortega-Hernández, 2022; p. 15.

 

Diagnosis: Lobopodian with vermiform body terminating in an elongate, flexible caudal spine; numerous broad, densely packed, lobopod-derived ventrolateral body flaps strongly overlapping successively; posterior ventrolateral body flaps decreasing in size linearly toward base of caudal spine until becoming flush with trunk; ventrolateral body flap posterior margins convex, anterior margin begins perpendicular to body wall before gradually curving posteriorly.

Occurrence: Pioche Formation, Combined Metals Member (Cambrian Series 2, Stage 4, Nephrolenellus multinodus Biozone), Lincoln County, Nevada; ....

Etymology: From the Latin adustus, meaning “burnt,” “singed,” or “sun-burnt,” in reference to the dramatic yellow, red, and black coloration of the two known specimens and to the arid conditions of the type locality.

Digital life reconstruction of Mobulavermis adustus, shown swimming in a Cambrian ocean alongside small bivalved arthropods and early chordates (speculative anterior morphology based on Kerygmachela kierkegaardi).

 twitter.com/Prehistorica_CM

Christian R.A. McCall. 2023. A large pelagic lobopodian from the Cambrian Pioche Shale of Nevada. Journal of Paleontology. First View. DOI: 10.1017/jpa.2023.63 

 twitter.com/Prehistorica_CM/status/1735015486272749775

 Non-technical Summary: Lobopodians are an iconic group of animals from the Paleozoic that includes Hallucigenia and Opabinia, as well as living animals such as tardigrades and velvet worms. They would also eventually give rise to the first arthropods by developing a hard, sclerotized exoskeleton. During the Cambrian, a rare subset of lobopodians possessed large swimming flaps, sometimes alongside ventral walking limbs. A new, large-bodied pelagic lobopodian from the Cambrian of Nevada is described, possessing more swimming flaps than any other lobopodian or radiodont.

[Paleontology • 2022] Needmorella simoni • A New Trilobite Genus (Dalmanitidae: Synphoriinae) from the Lower–Middle Devonian of West Virginia

Needmorella simoni 

Holloway & Scott, 2022

DOI: 10.1017/jpa.2022.96 

 twitter.com/scottforteacher 

Abstract 

The trilobite Needmorella new genus, with type species Needmorella simoni new genus new species from the late Emsian to mid-Eifelian Needmore Shale of West Virginia, is a distinctive member of the subfamily Synphoriinae. It also occurs in the same formation in Pennsylvania and Virginia. It is not very similar to other Devonian representatives of the subfamily and is considered to have its origins in a morphologically less-derived ancestor because it shares certain similarities with Silurian genera, including the very short anterior cephalic border unmodified by crenulations or spines, S2 that is not largely reduced to a deep pit adaxially, the relatively low inflation of L3, and the well-defined interpleural furrows on the pygidium. Other particularly distinctive characters of the genus include the very long genal spines and the abaxially inflated and expanded posterior pleural bands on the thorax and pygidium that project slightly distally. The conventional concept of the Devonian synphoriine Anchiopsis Delo, 1935 appears to be incompatible with the holotype of the type species, judging from the early illustrations of the specimen, and the genus could be a synonym of Synphoria Clarke, 1894.

 

David J. Holloway and Brian M. Scott. 2022. Needmorella, A New Trilobite Genus of the Synphoriinae (Dalmanitidae) from the Lower–Middle Devonian of West Virginia. Journal of Paleontology. DOI: 10.1017/jpa.2022.96

  twitter.com/scottforteacher/status/1600246058730524673

[PaleoOrnithology • 2023] Eudyptula wilsonae • Pliocene Fossils support A New Zealand Origin for the Smallest Extant Penguins (Sphenisciformes: Spheniscidae)

Eudyptula wilsonae

Thomas, Tennyson, Marx & Ksepka, 2023

DOI: 10.1017/jpa.2023.30

 twitter.com/KsepkaLab

Artwork by Simone Giovanardi twitter.com/GiovaFavazzi

massey.ac.nz

 

Abstract

A late Pliocene (3.36–3.06 Ma) exposure of the Tangahoe Formation on the North Island of New Zealand preserves close fossil relatives of many extant seabird clades. Here, we report an extinct member of the little penguin (Eudyptula Bonaparte, 1856) lineage from the Tangahoe Formation—the smallest extinct crown penguin yet known. Eudyptula wilsonae n. sp. is based on the nearly complete skulls of an adult and a fledged but immature individual. Both skulls show more slender proportions than modern little penguins and precede genome-derived estimates for the divergence between Eudyptula minor minor Forster, 1781 (endemic to New Zealand) and Eudyptula m. novaehollandiae Stephens, 1826 (native to Australia and recently established in New Zealand). This raises the possibility that the fossil taxon represents a lineage directly ancestral to extant little penguins. Our results support a Zealandian origin for little penguins, with subsequent Pleistocene dispersal to Australia and a more recent Holocene range expansion of Eudyptula m. novaehollandiae back into New Zealand.

Eudyptula wilsonae n. sp. 

 

Daniel B. Thomas, Alan J.D. Tennyson, Felix G. Marx and Daniel T. Ksepka. 2023. Pliocene Fossils support A New Zealand Origin for the Smallest Extant Penguins. Journal of Paleontology. First View, 1 - 11. DOI: 10.1017/jpa.2023.30

 twitter.com/KsepkaLab/status/1673396370432991245

  twitter.com/GiovaFavazzi/status/1673403728437583876

massey.ac.nz/about/news/little-fossil-penguin-species-discovered-with-possible-connection-to-korora/

[Paleontology • 2023] Archopterus anjiensis • The First Documentation of An Ordovician eurypterid (Chelicerata) from China

Archopterus anjiensis

Wang, Braddy, Botting & Zhang, 2023

 DOI: 10.1017/jpa.2023.21

Artwork: Dinghua Yang.

Abstract

An early form of eurypterids (Chelicerata), Archopterus anjiensis n. gen. n. sp., is described from the uppermost Ordovician Wenchang Formation of Anji County, Zhejiang Province, South China. It is the earliest record of eurypterids in China and likely the oldest representative of the Adelophthalmidae. The species, represented by a single specimen, is diagnosed by a ventrally preserved prosoma with a parabolic carapace, Hughmilleria-type prosomal appendages, a short vase-shaped metastoma, and a three-segmented type A (female) genital appendage. The specimen is preserved, together with diverse sponges, graptolites and occasional nautiloids, in a 10 m thick shale of marine deep-water setting. This finding extends the stratigraphic range of adelophthalmids from the previously recorded early Silurian into the Late Ordovician (some 10 million years older) and supports an earlier cryptic phase of eurypterid evolution in Gondwana.

Systematic paleontology

Subphylum Chelicerata Heymons, Reference Heymons1901

Order Eurypterida Burmeister, Reference Burmeister1843

Suborder Eurypterina Burmeister, Reference Burmeister1843

Family Adelophthalmidae Tollerton, Reference Tollerton1989

Genus Archopterus new genus

 

Etymology: Genus name from the Latin prefix arch-, meaning “ancient,” and -opterus, a common suffix for eurypterids, meaning “wing.”

Archopterus anjiensis n. gen. n. sp.

Holotype: NIGP 164906, Nanjing Institute of Geology and Palaeontology, CAS, China.

Diagnosis: Adelophthalmid with a parabolic carapace, Hughmilleria-type prosomal appendages, vase-shaped metastoma, and three-segmented type A (female) genital appendage.

Occurrence: Hirnantian (Metabolograptus persculptus Biozone) of the Wenchang Formation of Tianfucun, Anji County, Zhejiang Province, South China.

Etymology: The species is named after Anji County, where the type specimen was discovered.

 

Han Wang, Simon J. Braddy, Joseph Botting and Yuandong Zhang. 2023. The First Documentation of An Ordovician eurypterid (Chelicerata) from China. Journal of Paleontology. First View. DOI: 10.1017/jpa.2023.21

[PaleoOrnithology • 2023] Kumimanu fordycei & Petradyptes stonehousei • Largest-known Fossil Penguin provides insight into the early Evolution of sphenisciform Body Size and Flipper Anatomy

 

 Kumimanu fordycei & Petradyptes stonehousei

 Ksepka, Field, Heath, Pett, Thomas, Giovanardi & Tennyson, 2023

DOI: 10.1017/jpa.2022.88

otago.ac.nz

Life reconstructions by Simone Giovanardi.

 twitter.com/GiovaFavazzi

Abstract

Recent fossil discoveries from New Zealand have revealed a remarkably diverse assemblage of Paleocene stem group penguins. Here, we add to this growing record by describing nine new penguin specimens from the late Paleocene (upper Teurian local stage; 55.5–59.5 Ma) Moeraki Formation of the South Island, New Zealand. The largest specimen is assigned to a new species, Kumimanu fordycei n. sp., which may have been the largest penguin ever to have lived. Allometric regressions based on humerus length and humerus proximal width of extant penguins yield mean estimates of a live body mass in the range of 148.0 kg (95% CI: 132.5 kg–165.3 kg) and 159.7 kg (95% CI: 142.6 kg–178.8 kg), respectively, for Kumimanu fordycei. A second new species, Petradyptes stonehousei n. gen. n. sp., is represented by five specimens and was slightly larger than the extant emperor penguin Aptenodytes forsteri. Two small humeri represent an additional smaller unnamed penguin species. Parsimony and Bayesian phylogenetic analyses recover Kumimanu and Petradyptes crownward of the early Paleocene mainland NZ taxa Waimanu and Muriwaimanu, but stemward of the Chatham Island taxon Kupoupou. These analyses differ, however, in the placement of these two taxa relative to Sequiwaimanu, Crossvallia, and Kaiika. The massive size and placement of Kumimanu fordycei close to the root of the penguin tree provide additional support for a scenario in which penguins reached the upper limit of sphenisciform body size very early in their evolutionary history, while still retaining numerous plesiomorphic features of the flipper.

 

Life reconstructions of Kumimanu fordycei and Petradyptes stonehousei,

by Simone Giovanardi. twitter.com/GiovaFavazzi

Skeletal reconstructions of (left to right) Kumimanu fordycei, Petradyptes stonehousei, and Aptenodytes forsteri a modern emperor penguin.

Daniel T. Ksepka, Daniel J. Field, Tracy A. Heath, Walker Pett, Daniel B. Thomas, Simone Giovanardi and Alan J.D. Tennyson. 2023. Largest-known Fossil Penguin provides insight into the early Evolution of sphenisciform Body Size and Flipper Anatomy. Journal of Paleontology. First View , pp. 1 - 20

DOI: 10.1017/jpa.2022.88

UUID: zoobank.org/15b1d5b2-a5a0-4aa5-ba0a-8ef3b8461730

 www.otago.ac.nz/otagobulletin/news/otago0241045.html 

 twitter.com/GiovaFavazzi/status/1623393800134754304

[Paleontology • 2022] Lunataspis borealis • A New Species of the Ordovician (Late Sandbian) Horseshoe Crab Lunataspis from Kingston, Ontario, Canada

 

  Lunataspis borealis

Lamsdell, Isotalo, Rudkin & Martin, 2022

DOI: 10.1017/S0016756822000875

  twitter.com/FossilDetective

 

Abstract

Horseshoe crabs as a group are renowned for their morphological conservatism punctuated by marked shifts in morphology associated with the occupation of non-marine environments and have been suggested to exhibit a consistent developmental trajectory throughout their evolutionary history. Here, we report a new species of horseshoe crab from the Ordovician (Late Sandbian) of Kingston, Ontario, Canada, from juvenile and adult material. This new species provides critical insight into the ontogeny and morphology of the earliest horseshoe crabs, indicating that at least some Palaeozoic forms had freely articulating tergites anterior to the fused thoracetron and an opisthosoma comprising 13 segments.

Keywords: Xiphosura, Lunataspis borealis, development, ontogeny, Sandbian

    Lunataspis borealis sp. nov. specimens and interpretive drawings.
 (a) ROM IP 64616. (b) ROM IP 64617. (c) ROM IP 64618. (d) Interpretive drawing of ROM IP 64616. (e) Interpretive drawing of ROM IP 64617. (f) ROM IP 64618. Grey indicates preservation of organic cuticular material.

 All scale bars = 1 mm. Abbreviations: AN, axial node; CL, cardiac lobe; CN, cardiac node; FT, free tergites; LE, lateral eye; MR, marginal rim; OR, ophthalmic ridge; PT, pretelson.

 Systematic palaeontology

Chelicerata Heymons, Reference Heymons, 1901

Xiphosura Latreille, Reference Latreille, 1802

Xiphosurida Latreille, Reference Latreille, 1802

Lunataspis Rudkin, Young and Nowlan, Reference Rudkin, Young and Nowlan, 2008

Lunataspis borealis sp. nov.

Holotype. ROM IP 64616 (Fig. 1a, d), complete adult specimen in dorsal view preserving the dorsal prosomal carapace, thoracetron, postabdomen and telson.

Localities and horizon. Upper Member of the Gull River Formation, Simcoe Group, Upper Ordovician (Late Sandbian), in Kingston, Ontario, Canada (44° 15′ 52.7″ N, 76° 29′ 46.3″ W).

Diagnosis. Lunataspis with cardiac node positioned at base of cardiac lobe; lateral eyes located along middle of prosomal carapace length.

Etymology. The species name borealis is Latin for ‘northern’ and refers to the northerly latitude from which the species is known.

James C. Lamsdell, Phillip A. Isotalo, David M. Rudkin and Markus J. Martin. 2022. A New Species of the Ordovician Horseshoe Crab Lunataspis. Geological Magazine. First View, 1-5. DOI: 10.1017/S0016756822000875 

 twitter.com/FossilDetective/status/1577342449046921216

[PaleoMammalogy • 2022] Sivatupaia ramnagarensis • A New Genus of Treeshrew and Other Micromammals from the middle Miocene Hominoid Locality of Ramnagar, Udhampur District, Jammu and Kashmir, India

Sivatupaia ramnagarensis

Sehgal, Singh, Gilbert, Patel, Campisano, ... & Singh, 2022

DOI: 10.1017/jpa.2022.41 

twitter.com/APSGeo002 

Abstract

The fossil record of treeshrews, hedgehogs, and other micromammals from the Lower Siwaliks of India is sparse. Here, we report on a new genus and species of fossil treeshrew, specimens of the hedgehog Galerix, and other micromammals from the middle Miocene (Lower Siwalik) deposits surrounding Ramnagar (Udhampur District, Jammu and Kashmir), at a fossil locality known as Dehari. The treeshrew from Dehari (Sivatupaia ramnagarensis n. gen. n. sp.) currently represents the oldest record of fossil tupaiids in the Siwaliks, extending their time range by ca. 2.5–4.0 Myr in the region. Dietary analyses suggest that the new tupaiid was likely adapted for a less mechanically challenging or more frugivorous diet compared to other extant and fossil tupaiids. The occurrence of Galerix has only been recently documented from the Indian Siwaliks and the Dehari specimens help establish the likely presence of a relatively large Siwalik Galerix species in the Ramnagar region. In addition to the new treeshrew and hedgehogs, new specimens of the rodents Kanisamys indicus, Sayimys sivalensis, and Murinae indet. from Dehari help confirm that age estimates for the Ramnagar region are equivalent to the Chinji Formation in Pakistan, most likely corresponding to the middle to upper part of the Chinji Formation.

Sivatupaia ramnagarensis n. gen. n. sp.

 

Ramesh Kumar Sehgal, Abhishek Pratap Singh, Christopher C. Gilbert, Biren A. Patel, Christopher J. Campisano, Keegan R. Selig, Rajeev Patnaik and Ningthoujam Premjit Singh. 2022. A New Genus of Treeshrew and Other Micromammals from the middle Miocene Hominoid Locality of Ramnagar, Udhampur District, Jammu and Kashmir, India. Journal of Paleontology.  First View. DOI: 10.1017/jpa.2022.41

 twitter.com/APSGeo002/status/1530355738010263552

[Paleontology • 2022] Tomlinsonus dimitrii • A New Marrellomorph Arthropod from southern Ontario: A Rare Case of Soft-tissue Preservation on A Late Ordovician Open Marine Shelf

 Tomlinsonus dimitrii

Moysiuk, Izquierdo-López, Kampouris & Caron, 2022  

 

DOI: 10.1017/jpa.2022.11 

  twitter.com/CambroJoe

Abstract

Ordovician open marine Lagerstätten are relatively rare and widely dispersed, producing a patchy picture of the diversity and biogeography of nonmineralized marine organisms and challenging our understanding of the fate of Cambrian groups. Here, for the first time, we report soft-bodied fossils, including a well-preserved marrellomorph arthropod, fragmentary carapaces, and macroalgae, from the Late Ordovician (Katian) Upper Member of the Kirkfield Formation near Brechin, Ontario. The unmineralized elements and associated exceptionally preserved shelly biota were entombed rapidly in storm deposits that smothered the shallow, carbonate-dominated shelf. The marrellomorph, Tomlinsonus dimitrii n. gen. n. sp., is remarkable for its ornate, curving cephalic spines and pair of hypertrophied appendages, suggesting a slow-moving, benthic lifestyle. Reevaluation of marrellomorph phylogeny using new data favors an arachnomorph affinity, although internal relationships are robust to differing outgroup selection. Clades Marrellida and Acercostraca are recovered, but the monophyly of Marrellomorpha is uncertain. The new taxon is recovered as sister to the Devonian Mimetaster and, as the second-youngest known marrellid, bridges an important gap in the evolution of this clade. More generally, the Brechin biota represents a rare window into Ordovician open marine shelf environments in Laurentia, representing an important point of comparison with contemporaneous Lagerstätten from other paleocontinents, with great potential for further discoveries.

Tomlinsonus dimitrii n. gen. n. sp.

Joseph Moysiuk, Alejandro Izquierdo-López, George E. Kampouris and Jean-Bernard Caron. 2022.  

A New Marrellomorph Arthropod from southern Ontario: A Rare Case of Soft-tissue Preservation on A Late Ordovician Open Marine Shelf. Journal of Paleontology.  First View, 1 - 16. DOI: 10.1017/jpa.2022.11

  twitter.com/CambroJoe/status/1506995901583273984

[Paleontology • 2021] Description of the Metoposaurid Anaschisma browni (Temnospondyli: Metoposauridae) from the New Oxford Formation of Pennsylvania

Anaschisma browni Branson, 1905

in Gee & Jasinski, 2021. 

DOI: 10.1017/jpa.2021.30 

 twitter.com/StevenJasinski 

Illustration: Sergey Krasovskiy

Abstract

Metoposaurids are a widespread and ubiquitous constituent of Late Triassic non-marine paleoenvironments. In North America, this group is practically the only large-bodied temnospondyl clade, and is particularly well documented from the American southwest and south-central regions (Arizona, New Mexico, Texas). However, metoposaurids are poorly documented from eastern North America, with fragmentary, doubtfully diagnostic historical material such as “Dictyocephalus elegans” Leidy, 1856 and “Eupelor durus” Cope, 1866. The Zions View (early Norian?) locality in Pennsylvania preserves more-complete material, which previous workers noted as belonging to “Buettneria perfecta” Case, 1922 (=Anaschisma browni Branson, 1905). However, the material has never been described in a fashion that characterizes the anatomy or that justifies the taxonomic assignment, yet it would represent the most complete material in eastern North America and a substantial expansion of this taxon's geographic range. Here we redescribe the Zions View metoposaurid material in detail, differentiating it from Calamops paludosus Sinclair, 1917, the only other Late Triassic temnospondyl from the eastern seaboard, and demonstrating confident affinities with A. browni. Our study is the first to properly justify the taxonomic referral, underscoring the broader importance of proper documentation of voucher specimens, especially for potential geographic outliers. Anaschisma browni is thus the most widely dispersed metoposaurid. Its easternmost documentation underscores the importance of the undersampled and understudied metoposaurid record on the eastern seaboard for understanding the development of a metoposaurid zone of exclusivity in North America and demonstrates the need for further exploration to refine conceptualizations of Late Triassic tetrapod evolution.

Anaschisma browni Branson, 1905

 Bryan M. Gee and Steven E. Jasinski. 2021. Description of the Metoposaurid Anaschisma browni from the New Oxford Formation of Pennsylvania. Journal of Paleontology. 95(5); 1061-1078.  DOI: 10.1017/jpa.2021.30

  twitter.com/StevenJasinski/status/1390697374415208448

[Paleontology • 2020] New Rhenopyrgid Edrioasteroids (Echinodermata) and Their Implications for Taxonomy, Functional Morphology, and Paleoecology

Rhenopyrgus viviani Ewin, Martin, Isotalo & Zamora, 2020 

Silurian (lower Telychian), Jupiter Formation, Anticosti Island, Canada.

 (1, 2) Rhenopyrgus grayae (Bather, 1915), Upper Ordovician, Ayrshire, Scotland
(holotype E23470);  (6–7) Rhenopyrgus indet. 3; (9) Rhenopyrgus coronaeformis Rievers, 1961, Lower Devonian, Bavaria, Germany
(holotype SNSB-BSPG 1958 XV 50)

DOI: 10.1017/jpa.2019.65 

Illustration: Virgil Tanasa NHM.ac.uk

Abstract 

Rhenopyrgids are rare, turreted edrioasterid edrioasteroids from the lower Paleozoic with a distinctive and apparently conservative morphology. However, new, well-preserved rhenopyrgid edrioasteroid material from Canada, along with a review of described taxa, has revealed broader structural diversity in the oral surface and enabled a re-evaluation of rhenopyrgid functional morphology and paleoecology.

The floor plates in Rhenopyrgus viviani n. sp., R. coronaeformis Rievers, 1961 and, R. flos Klug et al., 2008 are well fused to each other and the interradial oral plate and lack obvious sutures, thereby forming a single compound interradial plate. This differs from other rhenopyrgids where sutures are more apparent. Such fused oral surface construction is only otherwise seen in some derived edrioblastoids and in the cyathocystids, suggesting homoplasy.

Our analysis further suggests that the suboral constriction could contract but the flexible pyrgate zone could not. Thus, specimens apparently lacking a sub-oral constriction should not necessarily be placed in separate genera within the Rhenopyrgidae. It also supports rhenopyrgids as epifaunal mud-stickers with only the bulbous, textured, entire holdfasts (coriaceous sacs) anchored within the substrate rather than as burrow dwellers or encrusters.

Rhenopyrgus viviani n. sp. is described from the Telychian (lower Silurian) Jupiter Formation of Anticosti Island, Québec, Canada and is differentiated by a high degree of morphological variability of pedunculate plates, broader oral plates, and narrower distal ambulacral zones. Specimens lacking or with obscured diagnostic plates from the Ordovician of Montagne Noire, France, and the Ordovician and Silurian of Girvan, Scotland are also described.

Systematic paleontology 

Phylum Echinodermata de Bruguière, 1791 (ex. Klein, 1734) 

Class Edrioasteroidea Billings, 1858 

Order Edrioasterida Bell, 1976 

Suborder Edrioblastoidina Fay, 1962 

Family Rhenopyrgidae Holloway and Jell, 1983 

Genera included.— Rhenopyrgus Dehm, 1961; Heropyrgus Briggs et al., 2017.

Figure 3. Rhenopyrgidae; all whitened with ammonium chloride.
 (1, 2) Rhenopyrgus grayae, Upper Ordovician, Lady Burn Starfish Bed, Girvan, Ayrshire, Scotland (holotype E23470): (1) details of oral surface with prominent collar plates and no suboral constriction apparent; black arrows highlight exposed floor plates in distal ambulacra; white arrow points to a small, exposed part of a plate of the suboral constriction, suggesting that suboral constriction could be contracted behind collar plates; (2) lateral view.
 (3, 4) Rhenopyrgus indet. 1, Silurian, Newland Formation, Newlands, Ayrshire, Scotland (E 62753): (3) lateral view of pyrgate zone, arrow points to enlarged plates interpreted here as collar plates; (4) oral view, black arrow highlights disarticulated large D-shaped oral ossicle.
(5) Rhenopyrgus indet. 2, Ordovician, Drummuck Series, Ardmillan, Girvan District, Ayrshire, Scotland (EE 16254); lateral view of pyrgate zone; note difference in size and morphology of the pyrgate ossicles suggesting it is different than R. grayae, which is found in similar age rocks that are geographically close; also note disarticulated ridged deltoidshaped plate closely associated with articulated pyrgate plates.
(6–8) Rhenopyrgus indet. 3: (6, 7) Foulon Formation (middle Floian), La Croix de Roquebrun, Saint-Nazaire-de-Ladarez, Hérault, France (UCBL-FSL 713312); (6) lateral view of whole specimen; (7) enlargement of the oral surface, showing confused plate articulation of this region; black arrow highlights possible oral ossicle; white arrows highlight collar plate series; (8) late Tremadocian, beneath Saint-Chinian Formation, Saint-Chinian, SW of Donnadieu, Babeau-Bouldoux, Hérault, France (UCBL-FSL 713316), lateral view.
(9–11) Rhenopyrgus coronaeformis Rievers, 1961, Lower Devonian, Emsian, Hunsrück Slate, Bavaria, Germany (holotype SNSB-BSPG 1958 XV 50): (9) detail of oral surface and proximal structures; (10) detail of oral surface; note complicated cover plate articulation surfaces; black arrow highlights grooved adambulacral margin of oral plate; (11) detail of coriaceous sac.

Abbreviations, O = oral plate. All scale bars represent 1 mm.

Genus Rhenopyrgus Dehm, 1961 

Type species.— Pyrgocystis (Rhenopyrgus) coronaeformis Rievers, 1961; Hunsrück Slate, Lower Devonian, (Emsian) of Germany.

Other species.— Rhenopyrgus coronaeformis Rievers, 1961; R. flos Klug et al., 2008; R. viviani n. sp.; R. sp. indet.1, formerly Pyrgocystis procera (Aurivillius) Bather, 1915; R. sp. indet. 2, R. sp. indet. 3, R. sp. indet. 4.; R. grayae (Bather, 1915); R. whitei Holloway and Jell, 1983; and R. piojoensis Sumrall et al., 2013.

Figure 5. Idealized reconstruction of Rhenopyrgus viviani n. sp. Silurian (lower Telychian), Jupiter Formation, Jupiter River, Anticosti Island, Canada. Note individuals with extended and contracted suboral constrictions and with only the coriaceous sac and very distal part of the pyrgate zone buried in the substrate.

Illustration: Virgil Tanasa

Rhenopyrgus viviani new species

Occurrence.— Cybèle Member to Pavillon Member, Jupiter Formation, Telychian, upper Llandovery, lower Silurian, Anticosti Island, Québec, Canada.

Etymology.— Named for the initial discoverer Mr. Travis Vivian.

Timothy A. M. Ewin, Markus Martin, Phillip Isotalo and Samuel Zamora. 2020. New Rhenopyrgid Edrioasteroids (Echinodermata) and Their Implications for Taxonomy, Functional Morphology, and Paleoecology. Journal of Paleontology. 94(1); 115-130.  DOI: 10.1017/jpa.2019.65

Newest member of echinoderm family revealed

nhm.ac.uk/press-office/press-releases/newest-member-of-echinoderm-family-revealed.html

nhm.ac.uk/discover/news/2019/september/unusual-fossil-worms-surprise-scientists.html