Calyptosuchus wellesi is an aetosaur known from the upper Blue Mesa Member and lowermost Sonsela Member of the Chinle Formation in Arizona, and the Tecovas Formation of the Dockum Group of Texas. The taxon is considered biostratigraphically informative and aids in correlating Upper Triassic strata across the southwestern United States. Our anatomical understanding of Calyptosuchus was primarily based on the holotype specimen from Texas and referred specimens, including several disarticulated elements from the Placerias Quarry in northern Arizona. We provide a re-interpretation of the holotype specimen and describe two new specimens referrable to Calyptosuchus from northern Arizona. Together these specimens provide new information on the cranial anatomy, including dentition, and the positional and intraspecific variation within the carapace and vertebral column of the taxon. This new evidence suggests that the skull anatomy of Calyptosuchus is more similar to that of Neoaetosauroides and Stagonolepis than to other aetosaurs. The dentition of Calyptosuchus supports recent hypotheses suggesting that aetosaurs were more omnivorous/faunivorous. The associated carapace expands our anatomical understanding of characters that vary among trunk paramedian osteoderms. We identify variation in the vertebral column within the trunk region, including the prominence of the centrodiapophyseal lamina and anatomy of the neural spine. Additionally, we report the first documentation of co-ossified sacral vertebrae within Calyptosuchus, which is also the first observation of this state within the Aetosauria outside of the Desmatosuchini. This suggests that co-ossification of the sacral vertebrae may be more prevalent within the Aetosauria than previously recognized.

http://zoobank.org/da3735b8-edf1-465d-820a-316174ed7bf9

Devonian stromatoporoid collections have been added to the Natural History Museum, London (UK) for over 100 years. The characteristics and systematic position of these specimens, however, have received little attention. In this study, 297 Devonian stromatoporoid specimens comprising material documented by H. A. Nicholson from the UK, Germany, United States, and Canada, plus specimens described by E. A. Ripper from Australia, were re-examined. Overall, 50 species belonging to 29 genera were systematically redescribed based on recent progress, mainly including Actinostroma, Petridiostroma, Stictostroma, Pseudotrupetostroma, and Parallelopora. Three-dimensional reconstructions reveal stromatoporoid architectural patterns, crucial for enhancing understanding and revision of stromatoporoid identification. This study underscores the significance of three-dimensional reconstruction in taxonomic research on stromatoporoids. The NHMUK material is combined with data from publications and the Paleobiology Database (PBDB) to perform a network analysis of the global occurrence of Devonian stromatoporoids at the generic level; this reveals a close relationship of the global stromatoporoid fauna during the Early Devonian, indicating a widespread distribution, despite this interval being regarded as a time of global stromatoporoid contraction. The Middle Devonian assemblage shows a much higher cosmopolitan occurrence in the context of the subsequent Eifelian–Givetian global stromatoporoid proliferation, consistent with the known pattern from other studies of Middle Devonian stromatoporoids. Overall, the NHMUK collections are a valuable resource to help understand the global occurrence of Devonian stromatoporoids.

Funisia dorothea Droser in Droser and Gehling, 2008 is an inferred metazoan-grade tubular organism, endemic to the Ediacara Member, Rawnsley Quartzite, of South Australia (~555–550 Myr), which is characterized by a hollow, elongate body constructed of uniserially repeating modular elements and is one of the most abundantly reported members of the Ediacara biota. Thus, Funisia Droser in Droser and Gehling, 2008 has broad significance for developing understanding of the Ediacara biota and provides a large dataset for testing hypotheses on the biological traits of Ediacaran tubular organisms. This study investigates size changes in Funisia’s modular elements to provide further insight into the paleobiology of this organism through the development of a holistic growth model. Results demonstrate that growth in Funisia was highly regulated to maintain uniform modular element width along the length of an individual and, thereby, an overall cylindrical form despite increasing module width throughout ontogeny. The growth model proposed here is compared with the pre-established growth model for another modular Ediacaran tubular organism, Wutubus annularis Chen et al., 2014, demonstrating that the two taxa had distinct growth patterns and disparate autecological strategies, despite a shared constructional morphology.

Biformites insolitus Linck, 1949 and very shallow, partially facetted, vertical burrows occur together in calcareous siltstone as convex hypichnia of sandstone on bedding soles within the Lower Devonian Clam Bank Formation, western Newfoundland. The ichnofossils occur within thinly interstratified siltstone and sandstone that accumulated within a physically stressed, euryhaline, peritidal paleoenvironment. B insolitus consists of straight to sinuous, narrow (2–3 mm), strap-like imprints commonly up to 7 cm long that display a medial axial depression and paired (opposite) conical (rounded blunt tipped) to irregular blocky and rectangular-shaped protuberances. These structures are interpreted to represent the impressions of ophiuroid arms, including representations of tube feet and ambulacral skeletal structure. Ornamentation detail appears proportional to the depth of an imprint and is a measure of the amount of downward force of an arm relative to horizontal motion. Apparent branching of imprints represents arm overprints. Incompletely facetted transverse sections of burrows, also filled with sandstone, warrant comparison with the ichnogenus Pentichnus, but incomplete preservation of a possible higher-order symmetry defers ichnotaxonomic designation. The imprints are very shallow (<1 cm) and fit with very near-surface burrowing as observed among some modern ophiuroids. The burrows are either a variant of Pentichnus, thereby expanding its current stratigraphic range, or broaden a unique ichnotaxobase of facetted burrows. A middle Paleozoic record of B. insolitus narrows the current disparity with the post-Cambrian ophiuroid skeletal record. Its spatial association with burrows in a peritidal paleoenvironment reinforces the complex behavior of ophiuroids, their ecological breadth, and opportunistic behavior.

This contribution identifies biogenic structures created by modern birds foraging in marginal aquatic settings and provides descriptions to facilitate their identification in the rock record. Biogenic structures related to foraging can be separated into those created by bills, such as peck marks, probe marks, gape marks, dabble marks, sweep marks, and bill-stir marks. Biogenic structures created by feet include stir tracks and paddle pits. Peck marks are created during visual foraging and result in shallow, solitary or paired, random or clustered, circular to subcircular pits and grooves. Probe marks are created during tactile foraging but are similar to peck marks, differing solely in their greater depth of penetration. Gape marks are formed when birds open their bill in the sediment resulting in elongated grooves. Dabble marks are larger ovoid divots emplaced by broad-billed waterbirds in subaqueous settings. Bill stirring occurs when a bird swishes its bill in a narrow trend on the sediment surface. Sweep marks are arcuate grooves emplaced in the sediment when long-billed birds forage by sweeping their bill side-to-side across the sediment–water interface.

Birds shuffling their feet in soft sediment is termed ‘foot-stirring’ and results in overprinted, side-by-side trackways. Foot-paddling dewaters the sediment and produces various pit morphologies with massive fill. Trackways emplaced during foraging are commonly characterized by variable stride length, stutter steps, and sudden changes in direction. ‘Trample grounds’ are produced by gregarious foraging flocks of birds. It is anticipated that illustrating and describing the structures produced by these behaviors will facilitate recognition of these commonly overlooked traces.

The evolutionary history of freshwater sponges (Porifera: Spongillida) in Australasia is poorly understood due to a paucity of fossils. A new genus and new species, Protooncosclera zealandiae n. gen. n. sp., family Potamolepidae, was discovered in southern New Zealand from lacustrine diatomites/spiculites of latest Oligocene–earliest Miocene of the Fossil-Lagerstätte at Foulden Maar. The fossil spicular complement is similar to that of the extant genus Oncosclera but differs from that and all other Spongillida genera by possessing a structured gemmular architecture armed by ornamented strongyles and strongyloxeas, with theca surrounded by a spicular cage of slender acanthoxeas, and a skeletal spicular complement of stout, smooth to spiny oxeas. This is the first fossil (pre-Quaternary) record of freshwater sponges from Australasia and fits into the Gondwana-like distribution of potamolepid freshwater sponges. Its discovery in a subtropical maar lake on the southwestern margin of Zealandia confirms a formerly wider geographic distribution of Potamolepidae in the Cenozoic, followed by range retractions related to post-Early Miocene climate cooling. The stratigraphic distribution of sponge remains at Foulden Maar demonstrates that sponges colonized the isolated maar lake soon after its formation, most likely by passive dispersal by water birds, and then thrived in the shallow water margins of the paleolake for ca. 130,000 years. Sponge remains, skeletal spicules and gemmules, frequently associated with coprolites indicate that sponges were consumed by one or more spongivorous taxa, presumably fish belonging to the Southern Hemisphere family Galaxiidae.

UUID: http://zoobank.org/72a81923-9766-4ae0-b980-28b2e3d98ebe

The present paper focuses on the middle to late Eocene Nummulites from the southern margin of the Tethys Ocean to address gaps in taxonomy of Nummulites, with emphasis on their biostratigraphic implications and paleobiogeographic distributions. Integration of biometric and morphological data with other taxonomic characters is used to define four Nummulites species (Nummulites midawaraensis Kenawy, 1978, N. biarritzensis d’Archiac and Haime, 1853, N. lyelli d’Archiac and Haime, 1853, and N. striatus (Bruguière, [1792]) from Fayum, Egypt. Biostratigraphically, three main biozones are identified. The Nummulites midawaraensis Biozone characterizes the Lutetian Midawara Formation. The N. lyelli Biozone heralds the Bartonian El-Gharaq Formation. The uppermost Priabonian Stage is demarcated by the N. striatus Biozone within the Birket Qarun Formation. These biozones match well with the Lutetian to Priabonian Tethyan larger benthic foraminiferal biozones. Distinct temporal changes and geographic distributions of the Nummulites assemblages distinguish remarkable middle to late Eocene paleobiogeographic provinces within the Tethys Ocean. Nummulites midawaraensis is probably endemic to the Egyptian southern Tethys Ocean, whereas the N. biarritzensis, N. lyelli, and N. striatus flourished throughout the Tethyan Realm, extending eastward from Spain to Pakistan and India. Notably, our findings strengthen the evidence for a strong connection between the Indo-Pakistani and Tethyan provinces during the Eocene. The relatively warm events throughout the middle to late Eocene led to an active carbonate factory and flourishing of calcite tests of Nummulites that favored clear waters and light under tropical to subtropical shallow-marine conditions.

“My first contact with Rod Feldmann was his voicemail message: ‘An incredible set of circumstances makes it impossible for me to come to the phone right now. Please leave a message and I will get back to you as soon as possible.’ I was considering coming to Kent for graduate school and I thought, ‘Wow, this guy is either really important or really arrogant.’ I was right and wrong. He was never arrogant, but always important, and eventually of utmost importance to me.”

The Llandoverian (Telychian) Schoolcraft Formation of Schoolcraft County in the Upper Peninsula of Michigan includes several intervals of exceptional preservation marked by abundant specimens of the noncalcified macroalga Thalassocystis striata Taggart and Parker, 1976. Here, two new noncalcified macroalgal species are described from one of these algal-Lagerstätten intervals. The monopodial thallus of Archaeobatophora gulliverensis new species resembles that of the living dasycladalean green alga Batophora Agardh, 1854 and consists of a cylindrical main axis bearing whorls of branched laterals. It is the second species to be assigned to Archaeobatophora Nitecki, 1976, the type species of which is known only from the Upper Ordovician of neighboring Delta County and the diagnosis of which is emended herein. The thallus of Earltonella swinehartii new species consists of a horizontal stolon that bears a series of upright pinnate fronds. This taxon broadly resembles the living bryopsidalean green alga Caulerpa Lamouroux, 1809 and is the second species to be assigned to Earltonella LoDuca in LoDuca et al., 2023, a genus otherwise known only from approximately age-equivalent strata in the Lake Timiskaming area of Ontario. Additionally, a new Thalassocystis striata occurrence is reported from the Schoolcraft Formation in neighboring Mackinac County, extending eastward the geographic range of this Codium-like bryopsidalean taxon within the Michigan Basin. Viewed in broader terms, the two new species show complex thallus morphologies consistent with a previously documented large-scale morphological pattern in the early Paleozoic evolutionary history of macroalgae and contribute to an emerging understanding of major early Paleozoic radiations of both dasycladalean and bryopsidalean algae that produced, by the mid-Silurian, diverse floras of siphonous green macroalgae broadly similar to those that thrive today in Florida Bay and the Bahama Banks.

We describe two new species of green algae in Dasycladales from Lower Cretaceous strata of the Eastern Carpathians (Romania), Suppiluliumaella schlagintweitii n. sp. and Triploporella loducai n. sp. The two new species display mineralization that coats most of the thallus, possibly casting light on their growth patterns. Suppiluliumaella schlagintweitii n. sp. displays a differentiated, club-shaped thallus with a very elongated vegetative part below the fertile zone (“head”) and a corticated external layer, suggesting a Neomeris type of growth. We further describe a possible mineralized juvenile growth stage. Triploporella loducai n. sp. is characterized by a rather short cylindrical thallus with a reduced vegetative region (sharp tapering rounded lower end), seemingly following a growth type resembling that of spherical Bornetella.

The late Silurian to Early Devonian floras in the South China Block provide important evidence for the radiation of early land plants, including the well-known Posongchong Formation and Xujiachong Formation of Yunnan Province and the Pingyipu Group of Sichuan Province. However, some taxa in these stratigraphic units are described on the basis of limited specimens, or even a single and/or poorly preserved specimen, and need further investigation. The re-investigation of specimen PB6458 from the Xujiachong Formation at the Xujiachong section near Xujiachong Village, Qujing City, Yunnan Province, which is the holotype of Zosterophyllum spathulatum Li and Cai, 1977, reveals some new characters of its strobilus, sporophylls, and sporangia and denies its assignment to Zosterophyllum Penhallow, 1892. Instead, this specimen should be assigned to Adoketophyton subverticillatum (Li and Cai) Li and Edwards, 1992. This taxonomic revision extends the paleogeographic distribution of Adoketophyton Li and Edwards, 1992 and further enhances this genus as one of the index fossils of Lower Devonian non-marine strata in the South China Block.

The Ovatoryctocara granulata Chernysheva, 1962 assemblage is a diverse fossil fauna that is important for global biostratigraphic correlation within Cambrian Series 2, Stage 4. The assemblage includes more than 60 invertebrate species in North Greenland from Freuchen Land to western Peary Land, but systematic documentation of all the fossils from the assemblage remains to be done. Here we expand on previous work by describing new mollusks and the problematic Stenothecoides from this assemblage in North Greenland, mainly from Freuchen Land. The identified taxa include Stenothecoides sp., Capitoconus borealis, Dorispira tippik Peel and Kouchinsky, 2022, Dorispira sp., Ressericonella pipalukae Oh and Peel, 2024, Ressericonella? sp., Mellopegma georginense Runnegar and Jell, 1976, Mellopegma simesi (MacKinnon, 1985), Yochelcionella gracilis Atkins and Peel, 2004, Eotebenna arctica Peel, 1989, Pelagiella sp., and three helcionelloid species in open nomenclature. These mollusks and stenothecoids facilitate faunal comparisons of North Greenland with Stage 4 to Miaolingian strata from other paleocontinents such as Siberia, Gondwana (Australia), and peri-Gondwana (North China), as well as within Laurentia.

Macroscopic, modular, morphologically simple skeletons occur in the uppermost Mural Formation (Cambrian, Epoch 2, Bonnia–Olenellus Biozone), west-central Alberta and adjacent east-central British Columbia. They represent organisms that lived almost exclusively in reefal environments dominated by archaeocyaths. Some were attached to archaeocyaths or less commonly other surfaces, and some grew downward, apparently from overhangs or cavities in reefs. Qualitative and quantitative data from a large number of specimens, most of which were serially thin sectioned, indicate that they represent a single, remarkably variable species. The skeletal structure ranges among specimens from entirely cerioid to partially to entirely labyrinthine with irregularly incomplete walls. There is also a wide range of variability in growth form among skeletons, in module size and wall thickness among and within skeletons, in module shape within skeletons, and in number and location of projections extending from the wall into some modules. Module increase occurred by peripheral expansion at the basal surface of the skeleton and longitudinal fission involving projections from the wall as module size increased during vertical growth. Walls of skeletons, now composed of calcite cement, were probably originally aragonite. Modular skeletons from the uppermost Mural Formation are assigned to Rosellatana jamesi Kobluk, 1984a, previously represented only by a few cerioid specimens from correlative strata in the Rosella Formation of north-central British Columbia. The skeletal structure and types of module increase in R. jamesi, and a few similar but less well-known Cambrian taxa from elsewhere in North America, suggest a general biologic affinity with hypercalcified sponges.

Despite being a conspicuous group in many fossil-bearing beds from the Tepuel–Genoa Basin, the knowledge of bryozoans from Patagonia is scarce and outdated. The majority of bryozoan records are known from faunal components of the Lanipustula patagoniensis Biozone (Carboniferous, upper Serpukhovian–Moscovian), in lower to middle levels of the Pampa de Tepuel Formation, Tepuel Group. For the present contribution, we conducted a taxonomic study on bryozoan samples from the lower third of the Pampa de Tepuel Formation at the type section, Sierra de Tepuel, central-western Patagonia, Argentina. We found Paraptylopora gondwanica n. sp. along with species of Penniretepora, Polyporella, Septatopora, Levifenestella, Rectifenestella, Spinofenestella, and others still under study. Most studied fenestrate species are restricted to central-western Patagonia, indicating a degree of biogeographical isolation, while a few imply faunal migration between the western and eastern margins of southern Gondwana during the Late Paleozoic Ice Age. The bryozoan growth habits association and accompanying fauna suggests a mid-shelf to upper-slope environment characterized by deep, low-turbidity, euhaline waters and a soft to firm substrate.

UUID: http://zoobank.org/3bf56286-9fd7-43c2-b5f6-417e86994d08

When studying extinct organisms, which phylogenetic methods are the most useful to determine patterns of evolutionary relationship? How well do current classifications reflect the patterns discovered? Using Athyridida (Upper Ordovician–Lower Jurassic) as a case study, we utilize parsimony, Bayesian Mk, asymmetrical rates, and fossilized birth–death process models, with and without character partitions, to compare results from different methods of inference, to test previous phylogenetic hypotheses and examine morphological character evolution in this long-lived group of extinct brachiopods. Because different phylogenetic methods utilize different models of evolution involving different sets of assumptions, they can result in different patterns of relationship, making it necessary to test multiple methods and then evaluate thoughtfully the various results obtained.

We discovered that the four main athyridide higher taxa we focus on largely maintain their coherence as clades in most of the analyses, but relationships among them vary substantially, with implications for the evolution of characters important in their classification. We were able to characterize in detail the athyridide external valve characters that are more variable than internal characters, quantifying the commonly held impression that internal features are more likely to be homologues and thus more reliable in identifying relationships than external characters. Because taxa in classifications are still frequently used as clade proxies in macroevolutionary studies, it is necessary to obtain and compare the most robust hypotheses of relationship among named taxa in order to evaluate both character homology and homoplasy and taxonomic fidelity to hypotheses of evolution.

Precambrian organic-walled microfossils preserved in fine-grained sedimentary rocks constitute the earliest fossil record of eukaryotic life. The Mesoproterozoic–Neoproterozoic transition coincided with major innovations in the evolution of early eukaryotes, including the radiation of crown-group lineages, represented in these rocks by candidate red algae, green algae, and fungi. However, the diversity of these early eukaryotes is yet to be fully explored. Here, we present a systematic description of the microfossil assemblage preserved in exceptional detail within sedimentary phosphatic nodules and bands in the Diabaig Formation of the ca. 1-Ga Torridon Group of northwest Scotland. Recent work has highlighted the lacustrine or estuarine nature of its depositional environment and confirmed that these fossils may include the oldest known non-marine eukaryotes. We identified 11 morphotaxa from newly collected material, including the new genus and species Minimarmilla multicatenaria, two undoubted eukaryotes, and two probable eukaryotes. The latter include Pterospermopsimorpha sp., and a new network-forming unnamed taxon. These microfossils present an important window on eukaryotic diversification in non-marine aquatic environments during the Mesoproterozoic–Neoproterozoic.

UUID: http://zoobank.org/5829c401-04fc-4229-9136-3963275826c6