Distinct Taxa Research Articles

A distinctive new species of Biatora (Ramalinaceae, Lecanorales) described from native European forests

AbstractA unique crustose lichen species was recently documented from various types of preserved forests across boreal and temperate Europe (Norway, Ukraine, the Czech Republic) and the Caucasus (Russia). It is formally described here as the new species Biatora amylacea. A phylogeny based on ITS and mtSSU sequences demonstrates that it belongs to an isolated group within the core of Biatora s. lat., together with the recently described B. radicicola. It is a distinctive taxon within the genus on account of its amyloid exciple, otherwise known only from members of the Biatora rufidula group. The new species is also characterized by amyloid thalline hyphae and the production of soredia with a blue-green pigment. This microlichen may serve as a bioindicator species of old-growth forests.

Unusual plesiosaur vertebrae from the Lower Jurassic Posidonia Shale of Germany

ABSTRACT The Toarcian (upper Lower Jurassic) strata of the world-renowned Posidonia Shale of Central Europe have yielded diverse assemblages of marine vertebrates. Some of them, such as those of the Holzmaden area in southwestern Germany, are among the best-preserved specimens of Lower Jurassic vertebrate taxa. Here, we provide a reassessment of ‘Plesiosaurus’ bavaricus, a long-overlooked plesiosaur taxon from the Posidonia Shale of northern Bavaria (southern Germany), established based upon two isolated cervical centra and a caudal vertebra. The cervical material exhibits an intriguing character combination, providing evidence for the presence of a distinct plesiosaur taxon in the upper Lower Jurassic of the Posidonia Shale of Germany. Additionally, we report another isolated cervical vertebra, likewise from the Posidonia Shale of Bavaria, that shows striking similarities to the type cervicals of ‘P’. bavaricus. Following our study of the Bavarian specimens, we hypothesise that, despite their substantial incompleteness, it seems likely that the material belonged to the same taxon, either species or a group of species, distinct from other plesiosaurs known from the Posidonia Shale.

Genetic structure of Ponto-Caspian trout populations shows gene flow among river drainages and supports resident Salmo rizeensis as a genetically distinct taxon.

To assess the genetic structure of Ponto-Caspian brown trout (Salmo trutta complex) populations, we analyzed both mitochondrial DNA sequences and genotypes at 10 microsatellite loci of fish caught in the Black Sea and from nine river catchments in Georgia, flowing into either the Black or Caspian seas. The results show that: (1) there is substantial genetic differentiation among Ponto-Caspian trout populations, both among the populations of different nominal species and within those of the same species; (2) the genetic distance between conspecific populations from the Black and Caspian Sea basins exceeds that among the populations within the same basin. Moreover, within drainages, genetic distance correlates with the geographic distance; (3) the Black Sea itself is not a barrier to gene flow among the watersheds draining into the Black Sea; (4) some populations in the headwaters of the rivers draining into the Black Sea Basin fall out of this pattern and likely form a separate, non-anadromous (resident) taxon, previously described from northeastern Turkey as Salmo rizeensis. This hypothesis is supported by mitochondrial DNA phylogeny. The presence of both anadromous and resident populations in a single river basin calls for a substantial re-thinking of speciation patterns and taxonomy of Eurasian brown trout.

Gelasia attariana (Scorzonerinae, Cichorieae, Asteraceae), a new species from NW of Iran, inferred from morphological and molecular data

Gelasia attariana is described as a new species from northwest of Iran, near the border to Azerbaijan. The new species is morphologically similar to G. cinerea and G. wendelboi, mainly because of sharing caulescent perennial life form, entire lanceolate leaves with 3–7 parallel veins, tomentose indumentum of phyllaries and glabrous achenes without carpopodium, but differs in plant height, indumentum type of stems and leaves, length/width ratio of leaves, leaves color, apex of leaves and length of achenes and pappus. Morphological comparisons and taxonomic relationships of G. attariana with its closely related taxa are discussed. Consistent with morphological data, molecular evidences based on nrDNA ITS sequences confirmed that the new species can be recognized as a distinct taxon from its close relatives. Description, images of living plants and distribution map of the new species are also provided.

Variation in shell morphology in the fossil freshwater gastropod Tanousia subovata (SETTEPASSI 1965) from the Mercure Basin (Middle Pleistocene, southern Italy): Distinct taxa or ecophenotypic variation? (Gastropoda Prosobranchia: Hydrobiidae)

The study of the shell plasticity of the extinct Hydrobiidae Tanousia subovata (settePassI 1965) resulted in a better understanding of the relationships between the shape of the organisms and the environment that influenced their life. Three populations, from distinct sections of the lacustrine Middle Pleistocene Mercure Basin (Basilicata-Calabria, southern Italy), have been investigated, using a landmark-based geometric morphometric analysis to quantify the morphological variability. Morphometric data and data coming from independent proxies (such as lithology and other fossils), already published on the studied basin, have been taken into account. Results have been interpreted to discriminate between internal and external factors influencing the shape of the shell. The geometric morphometric method proved useful to reveal some morphological variations between the three populations, which, following the comparisons with palaeoenvironmental data and with the literature appear to result from ecological or maybe chronological factors rather than indicating distinct species.

Chilean bee diversity: Contrasting patterns of species and phylogenetic turnover along a large‐scale ecological gradient

AbstractChile's isolation and varied climates have driven the evolution of a unique biodiversity with a high degree of endemism. As a result, Chile encompasses diverse environments, including the Mediterranean‐type ecosystem, a global biodiversity hotspot. These environments are currently threatened by anthropogenic land use change impacting the integrity of local biomes and associated species. This area is the most intensively sampled in the country with high endemicity of native bee species. Characterizing habitat requirements of bees is a pressing priority to safeguard these insects and the ecosystem services they provide. We investigated broadscale patterns of bee (Hymenoptera: Apoidea: Anthophila) diversity using newly accessible expert‐validated datasets comprising digitized specimen records from Chilean and US collections, and novel expert‐validated‐type specimen data for the bees of Chile. We used a generalized dissimilarity modeling (GDM) approach to explore both compositional and phylogenetic β‐diversity patterns across latitudinal, altitudinal, climate, and habitat gradients in well‐sampled bee assemblages in Central Chile. Using the GDM measures of increasing compositional and environmental dissimilarity, we categorized and compared the most important drivers of these patterns and used them to classify “wild bee ecoregions” (WBEs) representing unique assemblages. Turnover of bee assemblages was explained primarily by latitudinal variation (proxy for climate) from south to north in Chile. However, temperature variations, precipitation, and the presence of bare soil also significantly explained turnover in bee assemblages. In comparison, we observed less turnover in phylogenetic biodiversity corresponding to spatial gradients. We identified six de novo ecoregions (WBEs), all with distinct taxa, endemic lineages, and representative species. The WBEs represent distinct spatial classifications but have similarities to existing biogeographical classifications, ecosystems, and bioclimatic zones. This approach establishes the baseline needed to prioritize bee species conservation efforts across this global biodiversity hotspot. We discuss the novelty of this classification considering previous biogeographical characterizations and their relevance in assessing conservation priorities for bee conservation. We argue that Chile's WBEs highlight areas in need of funding for bee species surveys and description, distribution mapping, and strengthening of conservation policies.

Cryoxcellia borchgrevinki gen. nov., sp. nov., a new parasitic X-cell species in an Antarctic nototheniid fish, the bald notothen Trematomus borchgrevinki

X-cells were first described as an unknown cell type in northern hemisphere flatfish in 1969. Almost a decade later they were described in an Antarctic fish, the bald notothen Trematomus borchgrevinki, thus demonstrating their global distribution. Since this time, X-cells from various northern hemisphere fish species and from three other Antarctic fishes, the emerald notothen Trematomus bernacchii, the crowned notothen Trematomus scotti, and the painted notothen Nototheniops larseni have been identified as perkinsozoan parasites of the Family Xcellidae. Currently there are seven X-cell species described within this family. Here we report the morphology of X-cells isolated from the gill filaments of the bald notothen and include details of some of its division forms. Using short-read high-throughput DNA sequencing technology we have sequenced, assembled, and verified a 5347-bp region of the X-cell rRNA repeat unit that includes the complete 18S gene. In all cases, phylogenetic analyses identified this sequence as a distinct taxon and placed it among the perkinsozoan alveolates alongside other previously identified species in the X-cell family. Using a combination of morphological and genetic evidence we now describe a new X-cell genus and species, Cryoxcellia borchgrevinki gen. nov., sp. nov., from McMurdo Sound, Antarctica.

Morphological and molecular evidence supports the species status of the Italian endemic Coenagrion castellani Roberts, 1948 (Coenagrionidae)

Coenagrion castellani Roberts, 1948 was described from Italy as a distinct species almost 75 years ago but has generally not been recognised or was treated as a subspecies of C. mercuriale (Charpentier, 1840). Populations south of the Alps were recently shown to be completely isolated genetically from those in North Africa and elsewhere in Europe. As markings and male appendages also allow for easy separation in the field, C. castellani is best treated as a good species, the 146th odonate species known from Europe and the second one that is endemic to Italy. Its identification and occurrence are reviewed. North African populations are distinct genetically too, but not in morphology. Whether these should be treated as a distinct taxon, e.g. as the subspecies C. mercuriale hermeticum (Selys, 1872), requires further research.

Adaptations of Pseudoxylaria towards a comb-associated lifestyle in fungus-farming termite colonies

Characterizing ancient clades of fungal symbionts is necessary for understanding the evolutionary process underlying symbiosis development. In this study, we investigated a distinct subgeneric taxon of Xylaria (Xylariaceae), named Pseudoxylaria, whose members have solely been isolated from the fungus garden of farming termites. Pseudoxylaria are inconspicuously present in active fungus gardens of termite colonies and only emerge in the form of vegetative stromata, when the fungus comb is no longer attended (“sit and wait” strategy). Insights into the genomic and metabolic consequences of their association, however, have remained sparse. Capitalizing on viable Pseudoxylaria cultures from different termite colonies, we obtained genomes of seven and transcriptomes of two Pseudoxylaria isolates. Using a whole-genome-based comparison with free-living members of the genus Xylaria, we document that the association has been accompanied by significant reductions in genome size, protein-coding gene content, and reduced functional capacities related to oxidative lignin degradation, oxidative stress responses and secondary metabolite production. Functional studies based on growth assays and fungus-fungus co-cultivations, coupled with isotope fractionation analysis, showed that Pseudoxylaria only moderately antagonizes growth of the termite food fungus Termitomyces, and instead extracts nutrients from the food fungus biomass for its own growth. We also uncovered that Pseudoxylaria is still capable of producing structurally unique metabolites, which was exemplified by the isolation of two novel metabolites, and that the natural product repertoire correlated with antimicrobial and insect antifeedant activity.

Dinosaur teeth from the mid-Cretaceous Sunjiawan Formation of western Liaoning Province, China

ABSTRACT The mid-Cretaceous Sunjiawan Formation of western Liaoning Province, China has yielded a diverse of dinosaurs, yet without records of theropods. Recently, four isolated dinosaur teeth were discovered from the Sunjiawan Formation in Shuangmiao, Liangshuihe, Beipiao, Liaoning, China. They can be assigned to Tyrannosauroidea, Titanosauriformes and Hadrosauroidea based on morphological features. The tyrannosauroid tooth represents the first fossil record of Theropoda in the Sunjiawan Formation. The titanosauriform tooth is provisionally attributed to Borealosaurus considering that they are from the same horizon and locality. The hadrosauroid teeth represent a distinct taxon from Shuangmiaosaurus, the only known hadrosauroid from this formation. These findings increased the diversity of dinosaurs of the Sunjiawan Formation from three taxa to five.

Impact of 16S rRNA Gene Redundancy and Primer Pair Selection on the Quantification and Classification of Oral Microbiota in Next-Generation Sequencing.

This study aimed to evaluate the number of 16S rRNA genes in the complete genomes of the bacterial and archaeal species inhabiting the human mouth and to assess how the use of different primer pairs would affect the detection and classification of redundant amplicons and matching amplicons (MAs) from different taxa. A total of 518 oral-bacterial and 191 oral-archaeal complete genomes were downloaded from the NCBI database, and their complete 16S rRNA genes were extracted. The numbers of genes and variants per genome were calculated. Next, 39 primer pairs were used to search for matches in the genomes and obtain amplicons. For each primer, we calculated the number of gene amplicons, variants, genomes, and species detected and the percentage of coverage at the species level with no MAs (SC-NMA). The results showed that 94.09% of oral bacteria and 52.59% of oral archaea had more than one intragenomic 16S rRNA gene. From 1.29% to 46.70% of bacterial species and from 4.65% to 38.89% of archaea detected by the primers had MAs. The best primers were the following (SC-NMA; region; position for Escherichia coli [GenBank version no. J01859.1]): KP_F048-OP_R030 for bacteria (93.55%; V3 to V7; 342 to 1079), KP_F018-KP_R063 for archaea (89.63%; V3 to V9; undefined to 1506), and OP_F114-OP_R121 for both domains (92.52%; V3 to V9; 340 to 1405). In addition to 16S rRNA gene redundancy, the presence of MAs must be controlled to ensure an accurate interpretation of microbial diversity data. The SC-NMA is a more useful parameter than the conventional coverage percentage for selecting the best primer pairs. The pairs used the most in the oral microbiome literature were not among the best performers. IMPORTANCE Hundreds of publications have studied the oral microbiome through 16S rRNA gene sequencing. However, none have assessed the number of 16S rRNA genes in the genomes of oral microbes, or how the use of primer pairs targeting different regions affects the detection of MAs from different taxa. Here, we found that almost all oral bacteria and more than half of oral archaea have more than one intragenomic 16S rRNA gene. The performance of the primer pairs in not detecting MAs increases as the length of the amplicon augments. As none of those most employed in the oral literature were among the best performers, we selected a series of primers to detect bacteria and/or archaea based on their percentage of species detected without MAs. The intragenomic 16S rRNA gene redundancy and the presence of MAs between distinct taxa need to be considered to ensure an accurate interpretation of microbial diversity data.

Bulinus snails in the Lake Victoria Basin in Kenya: Systematics and their role as hosts for schistosomes.

The planorbid gastropod genus Bulinus consists of 38 species that vary in their ability to vector Schistosoma haematobium (the causative agent of human urogenital schistosomiasis), other Schistosoma species, and non-schistosome trematodes. Relying on sequence-based identifications of bulinids (partial cox1 and 16S) and Schistosoma (cox1 and ITS), we examined Bulinus species in the Lake Victoria Basin in Kenya for naturally acquired infections with Schistosoma species. We collected 6,133 bulinids from 11 sites between 2014-2021, 226 (3.7%) of which harbored Schistosoma infections. We found 4 Bulinus taxa from Lake Victoria (B. truncatus, B. tropicus, B. ugandae, and B. cf. transversalis), and an additional 4 from other habitats (B. globosus, B. productus, B. forskalii, and B. scalaris). S. haematobium infections were found in B. globosus and B. productus (with infections in the former predominating) whereas S. bovis infections were identified in B. globosus, B. productus, B. forskalii, and B. ugandae. No nuclear/mitochondrial discordance potentially indicative of S. haematobium/S. bovis hybridization was detected. We highlight the presence of Bulinus ugandae as a distinct lake-dwelling taxon closely related to B. globosus yet, unlike all other members of the B. africanus species group, is likely not a vector for S. haematobium, though it does exhibit susceptibility to S. bovis. Other lake-dwelling bulinids also lacked S. haematobium infections, supporting the possibility that they all lack compatibility with local S. haematobium, thereby preventing widespread transmission of urogenital schistosomiasis in the lake's waters. We support B. productus as a distinct species from B. nasutus, B. scalaris as distinct from B. forskalii, and add further evidence for a B. globosus species complex with three lineages represented in Kenya alone. This study serves as an essential prelude for investigating why these patterns in compatibility exist and whether the underlying biological mechanisms may be exploited for the purpose of limiting schistosome transmission.

Validation of the name Quercus infectoria subsp. veneris var. pfaeffingeri (Fagaceae)

AbstractQuercus infectoria Oliv. is a taxon with high morphological variation, and many infra‐specific have been described in this species, of which Q. infectoria Oliv. subsp. veneris (A.Kern) Meikle is present in the flora of Iran. In a taxonomic review of the Quercus L. taxa in Iran, based on morphological and micromorphological evidence, we recognized a new combination: Q. infectoria Oliv. subsp. boissieri (Reut.) O. Schwarz var. pfaeffingeri (Kotschy) Jamzad and Panahi, as a distinct taxon. Since the valid subspecific name for this taxon is subsp. veneris (A.Kern) Meikle var. pfaeffingeri, and the basionym of this name was not defined in the published manuscript. Here we correct the authorship and validate this name. Furthermore, we present the taxonomic history of Q. infectoria, descriptions of infraspecific taxa, a distribution map in Iran, ecological notes, and an identification key to infraspecific taxa.

Species diversity deflation: Insight into taxonomic validity of Garra species (Teleostei: Cyprinidae) from Dhofar Region in the Arabian Peninsula using an integrated morpho-molecular approach

Garra is the most species-rich genus of freshwater fishes in the Arabian Peninsula, including Oman, which has eight recognized, species restricted mainly to the Hajar and Dhofar mountains. Garra species from the Dhofar region in Oman are reviewed based on integrated morphological and molecular (COI) data of newly collected fishes from the type localities of G. sindhae and G. smartae, and a new population from Wadi Laggashalyon. No diagnostic character was found to distinguish the two species and the Laggashalyon population as distinct taxa. Garra dunsirei, another species endemic to a sinkhole at Tawi Attair, a very difficult area to access at a depth of about 211 m, was examined here based on the GenBank data and the diagnostic characters given in the original descriptions of the studied Garra species. In addition, the phylogenetic tree placed the sequenced Omani Garra fishes into nine groups with K2P sequence divergence of 0.8% (G. smartae and G. smartae_Laggasaylon); 1.2% (G. smartae and G. sindhae), and 14.5% (G. Shamal and G. dunsirei) in their COI barcode region. A molecular species delimitation approach using PTP, also detected one entity for Garra species from the Dhofar region (G. dunsirei, G. sindhae and the both populations of G. smartae), which is consistent with our morphological data. Therefore, based on absence of diagnostic characters, low genetic distance, and molecular species delimitation approach, we treat G. sindhae and G. smartae as junior synonyms of G. dunsirei.

The person-to-person transmission landscape of the gut and oral microbiomes

The human microbiome is an integral component of the human body and a co-determinant of several health conditions1,2. However, the extent to which interpersonal relations shape the individual genetic makeup of the microbiome and its transmission within and across populations remains largely unknown3,4. Here, capitalizing on more than 9,700 human metagenomes and computational strain-level profiling, we detected extensive bacterial strain sharing across individuals (more than 10 million instances) with distinct mother-to-infant, intra-household and intra-population transmission patterns. Mother-to-infant gut microbiome transmission was considerable and stable during infancy (around 50% of the same strains among shared species (strain-sharing rate)) and remained detectable at older ages. By contrast, the transmission of the oral microbiome occurred largely horizontally and was enhanced by the duration of cohabitation. There was substantial strain sharing among cohabiting individuals, with 12% and 32% median strain-sharing rates for the gut and oral microbiomes, and time since cohabitation affected strain sharing more than age or genetics did. Bacterial strain sharing additionally recapitulated host population structures better than species-level profiles did. Finally, distinct taxa appeared as efficient spreaders across transmission modes and were associated with different predicted bacterial phenotypes linked with out-of-host survival capabilities. The extent of microorganism transmission that we describe underscores its relevance in human microbiome studies5, especially those on non-infectious, microbiome-associated diseases.

A redescription of Palaeogekko risgoviensis (Squamata, Gekkota) from the Middle Miocene of Germany, with new data on its morphology.

After its original description, the Middle Miocene gekkotan Palaeogekko risgoviensis remained an enigma for palaeontologists due to a rather poor knowledge of its osteology and relationships. Coming from a single locality in southern Germany, this gecko lived in central Europe during a period when a single gekkotan lineage (i.e., euleptine sphaerodactylids) is confidently reported to have inhabited the continent. However, it is unclear whether P. risgoviensis may represent a member of this same lineage or a second clade of Gekkota. In order to shed light on this issue, the type material of P. risgoviensis is here redescribed, refigured and extensively compared with extinct and extant geckos from Europe. A phylogenetic analysis is also conducted in order to investigate its relationships. The new observations confirm the validity of the German species as a distinct taxon, and exclude the previously-suggested chimeric status of the type material of this gecko (with the exception of a single dentary included in the type series, which clearly belong to a different lizard). Phylogenetic relationships of Palaeogekko are still unclear, though, with different positions within the gekkotan tree recovered for the taxon. Nevertheless, it is confidently supported as a non-eublepharid gekkonoid, in agreement with hypothesys presented by other scholars.

On the identity of the Teyde dog-rose (Rosaceae): evidence for a new endemic taxon from Tenerife, Spain

In view of the high diversity found in many groups of vascular plants on the Canary Islands, Spain, the genus Rosa (Rosaceae) is poorly represented comprising only two native taxa (R. canina, R. rubiginosa). For the first time, this study provides detailed data on distribution, morphology, chorology and status of the so-called ‘Teyde dog-rose’, a representative of the Section Caninae, which occurs exclusively in the subalpine zone of the Cañadas del Teide, Tenerife. A survey of both native stock and herbarium material yielded that this population, currently classified as common dog-rose (Rosa canina L.), is phenotypically close to continental representatives of the glaucous dog-rose (Rosa dumalis Bechst.), from which, however, it differs in several traits such as floral characters and leaf morphology. Consequently, the population is formally recognized as a distinct taxon, Rosa dumalis ssp. nov. teydensis Weller & H. Reichert. The new subspecies appears to be extremely rare in the wild, with a low number of individuals growing at scattered localities mainly at shady rocky walls and adjacent habitats in a restricted area of the southern Cañadas. Consequently, according to IUCN criteria the taxon must be regarded as Critically Endangered.

<i>Corrigendum to</i>: White-footed dunnarts (<i>Sminthopsis leucopus</i>) in Queensland’s Wet Tropics, with the description of a new subspecies

A population of white-footed dunnarts (<i>Sminthopsis leucopus</i>) occurs in the Wet Tropics bioregion of tropical north Queensland, Australia separated by about 1800 km from conspecifics in temperate New South Wales, Victoria and Tasmania. We conducted targeted surveys for <i>S. leucopus</i> in north-east Queensland and obtained new records, including the first reported capture of the species in Queensland in 18 years. We assessed the genetic and morphological divergence of the north Queensland population against New South Wales, Victorian and Tasmanian <i>S. leucopus</i>, in conjunction with distribution and habitat differences, to assess whether this isolate should be described as a distinct taxon. Sequencing of the mitochondrial Cytochrome <i>b</i> gene revealed genetic divergence estimates of 2.3–2.8% and 4.3–4.8% between the north Queensland population and <i>S. l. ferruginifrons</i> (Victoria) and <i>S. l. leucopus</i> (Tasmania) respectively. Based on genetic divergence, cranial morphology, differences in habitat, and geographical isolation, we describe the north Queensland population as a new subspecies of <i>Sminthopsis leucopus</i>. We suggest a conservation classification of Endangered given its small distribution, apparent low density, tropical upland location and potential threats, especially related to climate change.

Hidden in plain sight: Tripneustes kermadecensis (Echinodermata: Echinoidea) is a junior synonym of the eastern Australian sea urchin Evechinus australiae described in 1878

Accurate taxonomy and descriptions of species are key to understanding biodiversity. The echinoid genus Tripneustes is an ecologically and commercially important taxon that includes the tropical Tripneustes gratilla gratilla and the recently described T. kermadecensis from Australia and New Zealand. While examining the Australian Museum collections to clarify the distributions of these two species in eastern Australia we found potential senior type material for T. kermadecensis. These specimens from Sydney Harbour were originally described in 1878 as Evechinus australiae by Tenison-Woods but neither illustrated nor redescribed in any subsequent report. We undertook molecular and morphological analysis of these specimens to determine whether T. kermadecensis and E. australiae represent two distinct taxa or not. This included micro-computed tomography, quantification of test traits and molecular genetic analysis. The COI sequence and morphology of Evechinus australiae matched that of Tripneustes kermadecensis. As such, T. kermadecensis is a junior synonym of Evechinus australiae. The correct designation of this taxon is therefore Tripneustes australiae (Tenison-Woods, 1878). ZooBank: urn:lsid:zoobank.org:pub:9B9E685C‐9C1C‐4645‐A799‐D97969BAA033

Ornithopod diversity in the Lower Cretaceous of Spain: New styracosternan remains from the Barremian of the Maestrazgo Basin (Teruel province, Spain)

New material of an iguanodontid styracosternan ornithopod from the Lower Cretaceous of the Iberian Peninsula is described. The cranial and postcranial skeletal remains are from the Barranco del Hocino-1 site. These fossils (Iguanodontidae sensu Xu et al., 2018) represent the first medium-sized styracosternan from the Upper Sequence of the Blesa Formation (Barremian). The new material is characterized by a unique combination of characters that suggest they correspond to a new taxon: the first caudal vertebra with a ventral keel, the ilium with the preacetabular process twisted along its long axis, the dorsal surface of the preacetabular process and the main body totally straight and slender, the dorsal surface above the ischiadic peduncle slightly swollen but not forming a bulge or everted rim over the main body, and the ventral surface of the ischiadic peduncle and the postacetabular process straight and parallel to the dorsal surface of the main body. The new material is part of a vertebrate fossil assemblage of disarticulated bones but it represents the most anatomically informative remains of an styracosternan of the Oliete subbasin and would be potentially a distinct taxon. Regarding the new material along with the seven known taxa, the fossil record from the Barremian of the Iberian Peninsula depicts the existence of great diversity and abundance of ornithopod dinosaurs during the Early Cretaceous in the southwest of Europe, indeed greater than in other regions and thus aiming to be a relevant paleogeographic scenario for the evolutionary history of the group.