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The first fossil loggerhead sea turtle (Cheloniidae: Caretta) from the North Pacific and its nannofossil biostratigraphy
No full textThe Taiwan waters (western North Pacific) include five sea turtle species without an associated fossil record. Here, we describe the first fossil sea turtle from Taiwan. This fossil material is a partial hypoplastron from the uppermost Yuching Shale in Tainan. The preserved morphology of this partial hypoplastron shows a slightly curved medial margin, a deep lateral notch, and a wide sutural anterior margin, indicating a taxonomic affinity to the genus Caretta. In comparison with extant Caretta, the preserved hypoplastral width at the sutural level (130.85 mm) suggests that this fossil belongs to an old subadult cf. Caretta. In addition, we also analyzed fossil foraminifera from the matrix of this hypoplastron, suggesting that the depositional environment was a continental shelf no more than 100 m deep. We further examined the nannofossils and found more than 200 calcareous nannofossils, including index fossils, such as Pseudoemiliania lacunosa, Helicosphaera sellii, and large Gephyrocapsa sp. (> 5.5 μm), corresponding to NN19a nannofossil biozone (Early Pleistocene in age). Given the first occurrence of the large Gephyrocapsa sp. and the last occurrence of Helicosphaera sellii, we narrowed down the age of this Pleistocene sea turtle from Taiwan to 1.57 to 1.28 million years ago. Our discovery of this Pleistocene sea turtle fossil represents not only the first cheloniid fossil in Taiwan but also the first well-dated fossil sea turtle from the global Pleistocene. The Taiwan waters during the Early Pleistocene may be a paleo-foraging ground for cf. Caretta, and future fieldwork and analysis should reveal a more detailed evolutionary history of sea turtles in the North Pacific. Our results also highlight the potential for more paleontological progress from Taiwan
Does intraspecific variation in juvenile Late Cretaceous ammonoids correlate with their systematic position, longevity and paleogeography?
No full textPhenotypic intraspecific variation of organisms is essential for evolution and, thus, has the potential to provide crucial insights into evolutionary dynamics. Additionally, ontogeny is often intricately linked with the evolutionary trajectories of organisms. In this study, we explore the relationship between the magnitude and ontogenetic pattern of intraspecific variation, and the interrelationships of organisms, their geographic distribution, and species duration. We analyzed the intraspecific variation in the whorl expansion rate (WER) of several Late Cretaceous ammonoid species, including Hypophylloceras ramosum, Phyllopachyceras ezoense, Gaudryceras tenuiliratum, Tetragonites glabrus, T. popetensis, Damesites damesi, Tragodesmoceroides subcostatus, Subprionocyclus minimus, Yezoites puerculus (all from Hokkaido, Japan), as well as Scaphites whitfieldi and Hoploscaphites comprimus (both from North America). Our results reveal a weak to moderate, negative correlation between the magnitude of intraspecific variation and geographic distribution. The correlation between intraspecific variation and species duration is weak. Notably, scaphitid and phylloceratid ammonoids exhibit a higher degree of intraspecific variation compared to other species, although no significant differences are apparent within each family. Additionally, scaphitid species from both Japan and North America display similar ontogenetic patterns of intraspecific variation. Hypophylloceras ramosum exhibits a pattern of intraspecific variation, differing from other normally coiled ammonoids. In other taxa, the pattern among species cannot be distinguished. These discoveries suggest that intraspecific variation, geographic distribution, and species duration are, at least, not positively correlated. However, contrary to previous studies, our data suggest a potential link between intraspecific variation and the interrelationships of species (relative phylogenetic position). Further research involving the analysis of more taxa, multiple morphological parameters examined over longer ontogenetic stages, and the development of a robust phylogenetic hypothesis are necessary to better understand these associations
Notes on Neotropical litter-gathering Rubiaceae, and distinction between Faramea tinguana from southern Brazil, and F. humicapiens sp. nov. from French Guiana
No full textBackground and aims – Single-stemmed plants 20–100 cm tall, with sessile or subsessile leaves in terminal rosettes gathering leaf litter, and axillary, 1–3-flowered inflorescence, from the state of Rio de Janeiro, southern Brazil, and from French Guiana, have traditionally been identified as Faramea tinguana. The disjunction of more than 3,200 km air distance between French Guiana and Rio de Janeiro stimulated an in-depth analysis of the specimens from those regions to evaluate if any morphological character might distinguish them. Material and methods – This study is based on examinations of herbarium specimens, material preserved in 60% ethanol, and field observations. Herbarium specimens were studied either on site or through loans from the CAY, CEPEC, G, G-DC, K, L, MO, NY, P, RB, U herbaria. Digital images of herbarium specimens were analysed through virtual herbaria. Traditional practices of herbarium taxonomy have been applied. A preliminary conservation status assessment of each species studied was made using the IUCN Red List Categories and Criteria. Results – The names F. tinguana and F. megalophylla are here lectotypified, and are treated as synonymous. Numerous reproductive characters support a clear distinction between the specimens from Rio de Janeiro and those from French Guiana traditionally identified as F. tinguana. Hence, the two distant populations are here treated as two distinct species. Faramea humicapiens, endemic to French Guiana, is newly described, and F. tinguana is restricted to the state of Rio de Janeiro. Faramea humicapiens is evaluated as Vulnerable and F. tinguana as Critically Endangered. A discussion on Neotropical litter-gathering Rubiaceae is also presented
Two new species of Tropodiaptomus Kiefer, 1932 (Copepoda, Calanoida, Diaptomidae) from temporary waters in Thailand and Cambodia with a key to Southeast Asian species
No full textTwo new copepod species of the species-rich genus Tropodiaptomus, collected from temporary water habitats in Southeast Asia, are described. A critical morphological comparison has revealed that the two new species, T. lannaensis sp. nov. from Thailand and T. kampucheaensis sp. nov. from Cambodia, closely resemble their respective congeners, T. ruttneri (Brehm, 1923) and T. doriai (Richard, 1894). However, T. lannaensis sp. nov. can be distinguished from other congeners, including T. ruttneri, by the following characters of the male P5: (1) the inner margin of the right basis has one small semicircular knob and one triangular knob; (2) the right second exopodal segment has a long, slender accessory spine inserted at the proximal third of the outer margin; and (3) the inner margin of the left exopod has a bilobed saw with a series of large denticles and smaller denticles near the distal end. Tropodiaptomus kampucheaensis sp. nov. is different from all other species because it has (1) only one longitudinal hyaline lamella on the inner margin of the basis of the male right P5; (2) the one-lobed distal inner margin on the male left P5 exopod with uniform teeth; (3) the asymmetrical female genital-double somite (right margin expanded sub-proximally); and (4) the extraordinarily long inner seta on the P4 coxa of both sexes. The biogeography and keys to the species of Tropodiaptomus in Southeast Asia are presented
Round ligament varicosity – a rare mimicker of inguinal hernia in pregnancy
No full textIntroduction: Round ligament varicosity (RLV) is a rare condition in pregnancy, with approximately 80% of the women being referred by gynaecologists with clinical suspicion of groin hernia. Herein, we report a case of right RLV with a brief review of the literature to raise attention to this condition that can easily be misdiagnosed as a groin hernia thus leading to unnecessary interventions. Case report: A 26-year-old woman presented with dull intermittent pain in the right groin and a lump in the right groin that appeared during the third trimester of the first pregnancy and disappeared after the delivery. The physical exam was normal, so RLV was suspected. During the second pregnancy, she complained of a slight swelling that appeared in the third trimester, accompanied by mild discomfort in the right groin. The physical exam revealed a small lump visible only in a standing position. The US demonstrated multiple dilated and tortuous veins in the inguinal canal that collapsed on pressure and became more prominent on the Valsalva manoeuvre. Doppler US confirmed the venous flow. The exam performed by a vascular surgeon showed multiple dilated pelvic veins and patent blood flow in the major veins of both limbs. Conclusion: The RLV can easily be misdiagnosed as a groin hernia. The exact and timely diagnosis of RLV is critical to avoid unnecessary surgery and diminish the anxiety of the pregnant woman. The differential diagnosis of RLV is relatively straightforward when the surgeon is aware of RLV and the specific US findings
Two new rarely collected species of Annonaceae from the Peruvian Amazon
No full textWhile preparing a taxonomic revision of the Neotropical genus Klarobelia Chatrou (Annonaceae), two species new to science – Klarobelia icoja S.Lara & Chatrou, sp. nov., and Malmea abscondita Chatrou & Gees, sp. nov. – were discovered. Both species are known from only two collections, made in Amazonian Peru. We clarify their generic placement and taxonomic identity based on a comparison of morphological characters with previously described species and on molecular phylogenetic analysis of four plastid markers. The conservation status of both species is assessed following IUCN criteria, and line drawings and distribution map are provided
A new Dichocarpum W.T.Wang & P.K.Hsiao (Ranunculaceae) species from Guizhou, China
No full textA new species of Dichocarpum from Guizhou, China, is described and illustrated. Morphologically, it resembles D. auriculatum, D. trifoliolatum, D. basilare, D. franchetii, D. arisanense, D. adiantifolium, and D. uniflorum. However, it differs from these seven species by its creeping stolons, 3–5-foliolate leaflets with scalloped or suborbicular shape, and an inflorescence consisting of a single flower. The phylogenetic relationship with other species of the genus is examined based on three chloroplast gene segments (matK, trnL-F, trnH-psbA) and one nuclear ribosomal DNA region (ITS). In addition, an identification key to all Chinese species of Dichocarpum is provided
Lygodium palmatum subsp. puskariorum (Lygodiaceae), a new subspecies from the eastern USA
No full textLygodium palmatum (Bernh.) Sw. subsp. puskariorum Metzgar, subsp. nov. (Lygodiaceae) is described from the eastern USA. This taxon differs from Lygodium palmatum subsp. palmatum by its glabrous leaf undersides, absence of hairs along the fertile and sterile segment petioles, and its geographic range. It is the less widely distributed of the two subspecies
Movement ecology of the Sacred ibis (Threskiornis aethiopicus) outside of its natural range
No full textUnderstanding the movements of alien species in newly colonized territories is crucial for addressing the challenges posed by global transformations and threats to biodiversity conservation. In this study, we used mark-resight data to investigate the dispersal movements of the sacred ibis (Threskiornis aethiopicus; class: Aves) in Italy, which were virtually unknown until now. We analyzed data from 357 color-ringed ibises, the majority of which were marked as nestlings, including six hybrids with the African spoonbill (Platalea alba). Resightings revealed a tendency towards philopatry, with most observations occurring within 10 km of the original colony. However, few individuals travelled much farther, with maximum recorded distances exceeding 300 km from the ringing site. The average long-distance travel speed was 15.4 km per day. Movement directions showed clustering along both the North-South and East-West axes, influenced by colony location. Landfills emerged as significant feeding sites, particularly in winter. Age class had a significant negative effect on dispersal distance, whereas timing of hatching showed a positive effect. Although philopatry was predominant, our results indicate that the species retains the potential for longer-range dispersal under certain conditions. While based on a limited number of individuals, such movements could nonetheless facilitate expansion into distant areas, particularly given the availability of suitable habitats. These findings provide the first evidence of the dispersal capability of the sacred ibis outside its native range and should be used to inform management actions aimed at mitigating the potential effects of this invasive species
Editorial
No full textDear Readers,I am very pleased to announce today the tenth J.UCS issue of 2025. In this issue, various topical aspects of computer science are covered in 5 articles by 13 authors from 5 countries (Brazil, Croatia, Germany, India, Spain). As always, I would like to thank all the authors for their sound research and the editorial board for their highly valuable review effort and suggestions for improvement. These contributions sustain the quality of our journal. I would also like to express my sincere thanks to the KOALA Initiative and its team for their financial support, without which the J.UCS team would not be able to publish our journal.In an ongoing effort to further strengthen our journal, I would like to expand the editorial board: If you are a tenured associate professor or above with a strong publication record, you are welcome to apply to join our editorial board. We are also interested in receiving high-quality proposals for special issues on new topics and trends. Please consider yourself and encourage your colleagues to submit high-quality articles or special issue proposals for our journal.In this regular issue, I am very pleased to introduce the following 5 accepted articles: Rodrigo Costa Camargos and Ismar Frango Silveira from Brazil explore in their research the application of Explainable Artificial Intelligence (XAI) techniques to mitigate cognitive biases in predicting student dropout comparing Explainable Boosting Machine (EBM), Logistic Regression and XGBoost models.Sorav Kumar Singh, Alak Roy and Rajneesh Raushan from India focus their research on underwater wireless sensor networks and propose a Residual Energy-Aware Fuzzy-Based Clustering Algorithm (REAFCA), which presents an enhanced framework to improve network performance and addresses issues with energy usage.Juan Morales-García, Fernando Terroso-Sáenz, Andrés Bueno-Crespo, and José M. Cecilia from Spain discuss in their research the analysis of synthetic timeseries as an enabler to improve region-based human mobility forecasting by applying Generative adversarial network (GANs) to generate synthetic time-series mobility data.Igor Tomičić, Petra Grd, and Andrija Bernik from Croatia present in their research a comprehensive analysis of the integration of artificial intelligence into threat intelligence (TI) systems focusing on its potential to enhance cybersecurity operations by an extensive literature review including machine learning, deep learning, and natural language processing for automating threat detection, classification, and analysis.And last but not least, Daniel Spiekermann from Germany investigates in his research the real-world behaviour of network traffic within virtualized environments to identify the key factors that impact packet dynamics, including VM operations, multi-tenancy, user customization, and hardware adjustments.Enjoy Reading!Best regards,Christian Gütl, Managing Editor-in-Chie