Range Extension Research Articles

Range extension of Bunocephalus larai Ihering, 1930, Banjo Catfish (Siluriformes, Aspredinidae), in the Ivaí river basin, Upper Paraná River, Brazil

We report the occurrence of Bunocephalus larai in the Ivaí river basin, and expand the geo‑ graphic distribution of this species to southern latitudes of the Upper Paraná river basin. Four individuals were captured through electrofishing in the Muquilão River, a tributary of the Ivaí River, Paraná, Brazil. The sampled site was within a conservation unit in the municipality of Iretama. The captures occurred in a marginal backwater of a 20–40 m wide stretch and 0.3–0.7m deep, characterized by sand/clay and leaf litter as predominat bottom substrate. Our study demonstrates the importance of ichthyofaunistic studies in headwaters of rivers.

Genetic signature of demographic history explains the current sympatric distribution of sibling species of Craseomys (Rodentia: Arvicolinae)

Abstract Sequences of mitochondrial DNA were analysed in two vole species (Craseomys rex and Craseomys rufocanus), which are closely related based on phylogeny, morphology, and ecology. In Hokkaido, Japan, they occur sympatrically in forests, but Craseomys rufocanus also inhabits open fields. Capture records of 2532 specimens from 114 localities confirmed the widespread and fragmented distribution of Craseomys rufocanus and Craseomys rex and indicated that abundance of Craseomys rufocanus was 9.2–19.8 times higher than that of Craseomys rex. The phylogenetic tree illustrated four regional clades for Craseomys rex, but no distinct clades for Craseomys rufocanus. The observed mismatch distribution of Craseomys rufocanus matched with a spatial expansion model, indicating population expansion through range extension with frequent migration. Using 47 haplotypes from 151 Craseomys rex and 302 haplotypes from 1037 Craseomys rufocanus, a skyline plot revealed that Craseomys rufocanus increased during the Last Glacial Cycle (LGC) when grassy vegetation dominated forests. Craseomys rex expanded following forest recovery following LGC survival. The current effective population size (Ne) of Craseomys rufocanus was 15.9–33.8 times higher than that of Craseomys rex, in good agreement with capture records. Population expansion of Craseomys rufocanus during the LGC resulted in range extension and its current distribution, whereas the current range of Craseomys rex was derived from glacial refugia.

An updated checklist of snakes (Reptilia: Squamata) in northeastern India derived from a review of recent literature

This paper reviews studies of the snakes of northeastern India published between 2001­­­­­­­ and 2024 identified from searchable databases, covering diversity, range extension, distribution records, new genus, new species, redescription, rediscovery, and taxonomic revision. This analysis of the literature and publicly available information presents an updated checklist of 126 snake species representing 12 families and 46 genera, along with their distribution across states in northeastern India and their IUCN Red List status. The study also reveals a research gap in some northeastern states that provides opportunities for further regional studies.

Range Extension of the Genus Lycogaster Shuckard, 1841 (Hymenoptera: Trigonalyidae) to India with the Species L. rufiventris (Magretti, 1897) from Northeastern India.

Range Extension of the Genus Lycogaster Shuckard, 1841 (Hymenoptera: Trigonalyidae) to India with the Species L. rufiventris (Magretti, 1897) from Northeastern India.

Dynamic range extension method for optical frequency shift detection based on temperature–current tuning

Dynamic range extension method for optical frequency shift detection based on temperature–current tuning

Analysis of Water Film Distribution and Aerodynamic Performances of High-Speed Train Under Rainfall Environment

The current research on the aerodynamic performance of the train running in rainy weather is primarily concerned with the trajectory of the raindrops and the aerodynamic variation of trains caused by raindrops. In fact, water film will generate on the train body when raindrops hit the train, which interacts with the flow field around the train, and would probably affect the aerodynamic performance of the train. In this paper, based on shear stress transport (SST) k-w turbulence model and Euler-Lagrange discrete phase model, the aerodynamic calculation model of a high-speed train under rainfall environment is established. The LWF (Lagrangian wall film) is used to simulate the water film distribution of the high-speed train under different rainfall intensities, and the aerodynamic performance of the train are studied. The calculation results show that raindrops will gather on the train surface and form water film under rainfall environment. With the extension of rainfall time, the thickness and coverage range of water film expand, and the maximum thickness of water film can reach 4.95 mm under the working conditions in this paper. The average thickness of water film on the train body increases with the rainfall intensity. When the rainfall intensity increases from 100 mm/h to 500 mm/h, the average water film thickness will increase by 3.26 times. The velocity of water film in the streamlined area of head car is larger than that in other areas, and the maximum velocity is 22.14 m/s. Compared with the rainless environment condition, the skin friction coefficient of the high-speed train increases and the average value will increase by 10.74% for a rainfall intensity of 500 mm/h. The positive pressure and resistance coefficient of the head car increase with the rainfall intensity. This research proposes a methodology to systematically analyze the generation of water film on the train surface and its influence on the train aerodynamic performance; the analysis can provide more practical results and can serve as a reference basis for the design and development of high-speed trains.

Rediscovery and redescription of Ixalus garo Boulenger, 1919, and Ixalus kempiae Boulenger, 1919, with a reassessment of the taxonomic status of Raorchestes cangyuanensis Wu, Suwannapoom, Xu, Murphy & Che, 2019 and the description of a new species from the Garo Hills of Meghalaya

Bush frogs from Garo and Khasi Hills were collected, and a thorough examination based on morphology and geographic distribution revealed that two of the populations sampled from Garo Hills during this study agree with the holotypes and descriptions of the taxa Ixalus garo and I. kempiae, described more than a century ago. The original description lacked information on several morphological characters, genetic material, and photographs of the species in life. The absence of such information posed challenges in field identification of these species. Our phylogeny shows them to be nested within the Raorchestes clade, and therefore, we allocate these two species to this genus and formally announce their rediscovery. We also redescribe these two species here based on additional adult vouchers and report geographic range extensions from new localities. Based on molecular and morphological analysis, we reassess the status of the recently described Raorchestes cangyuanensis, resulting in its placement under the subjective junior synonymy of R. kempiae. We also describe a morphologically distinct new species from this region. This paper bridges an important gap in the knowledge of the genus Raorchestes in this part of India and highlights the importance of systematic surveys in documenting and understanding amphibian diversity in the region.

Swimming in the Sahara: a new locality record and range extension of Natrix maura (Linnaeus, 1758) (Squamata, Colubridae) from central Algeria

Natrix maura, commonly known as the viperine snake, is a widespread and common semi-aquatic species in the western Mediterranean region. This study reports a new locality record of N. maura from central Algeria, significantly extending the species’ known range. Additionally, we provide an updated distribution map of N. maura in Algeria, compiled from a comprehensive dataset of occurrence records. Our findings emphasize the need for extensive herpetofaunal surveys in the country’s underexplored regions. Dataset published through GBIF (DOI: 10.15470/fe3689)

Sharks and Rays of Northern Australia's Roper River, with a Range Extension for the Threatened Speartooth Shark Glyphis glyphis.

Northern Australia is considered a 'lifeboat' region for globally threatened shark and ray species (elasmobranchs), although much of the region is understudied. The Roper River in the Northern Territory's Gulf of Carpentaria has been inadequately surveyed, with most elasmobranch data gained opportunistically through freshwater fish surveys. This study aimed to report the occurrence of elasmobranch species in the Roper River through targeted field surveys conducted between 2016 and 2024 and to review data from other sources. Four euryhaline species were recorded, comprising two sharks, a sawfish, and a stingray. Records of the globally Vulnerable speartooth shark (Glyphis glyphis) represented a significant range extension and the documentation of a new reproductive population. Records of the Critically Endangered largetooth sawfish (Pristis pristis) extended almost 400 km upstream, highlighting extensive use of the river system. A predominantly marine species, the Critically Endangered giant guitarfish (Glaucostegus typus) was observed in brackish estuarine waters, approximately 15 km upstream from the river mouth. Further research is required to develop a more thorough understanding of abundance, life history, and population connectivity for these species in this river system. Given the documentation of threatened species, the potential impacts of fisheries, water allocations, and climate change require assessment.

Diversity and Abundance of Ants from Tehsil Nerwa of District Shimla, Himachal Pradesh, India

The present study focused on diversity, abundance and functional groups of ants from Tehsil Nerwa of District Shimla, Himachal Pradesh. A total of 693 ant specimens representing 33 species belonging to 22 genera of 4 subfamilies were collected. Myrmicinae is the most diverse and abundant subfamily. Dolichoderinae is the least diverse subfamily while Ponerinae is the least abundant subfamily. During this study also reports range extension of 3 invasive species. 2 Species are endemic to the region. In this study seven functional groups of ants were identified. These are: “Generalized Myrmicinae”, “Opportunists”, “Subordinate Camponotini”, “Hot climate Specialists”, “Cold climate Specialists”, “Cryptic Species”, and “Specialist Predators”. The area is very susceptible to anthropogenic activity, as indicated by the prevalence of invasive species there. Therefore, some stringent measures should be taken to preserve the deteriorating ecosystem of the study area.

Regional range extension of two xanthid crab species (Decapoda, Brachyura) to the mid-Sanriku Coast, the coldest waters off Honshu, Japan

Abstract This paper reports the first occurrences of two brachyuran crab species of the family Xanthidae MacLeay, 1838, viz., Actaea semblatae Guinot, 1976 and Gaillardiellus orientalis (Odhner, 1925), from the mid-Sanriku Coast, along the Pacific coast of northeastern Japan. While these records do not represent the northern limit of distribution of these species, they do show a range extension into the coldest waters of Honshu, the main island of Japan, probably due to global warming and changes in flow patterns of the local sea currents.

Range extension of the Mexican-endemic killifish Profundulus chimalapensis (Cyprinodontiformes: Profundulidae), with comments on its phylogenetic placement and possible intergeneric hybridization with Tlaloc Álvarez & Carranza 1951.

Recent ichthyological surveys in southern Mexico resulted in the unexpected discovery of populations of P. chimalapensis outside its distribution range, broadening its extent of occurrence to a total of three river basins (Coatzacoalcos [original], Grijalva, Ostuta) and two versants (Atlantic [original] and Pacific). The taxonomic nature of these populations was further investigated using comparative genetic data in a phylogenetic framework. Our results include the first assessment of the phylogenetic position of P. chimalapensis with respect to other Profundulus species and imply a sister-group relationship with P. oaxacae. Remarkably, our results also imply a close phylogenetic affinity of some P. chimalapensis samples with the genus Tlaloc, which we interpret as possible evidence of intergeneric hybridization, a phenomenon previously unreported in the family. If our interpretation in this regard is correct, it raises several broader evolutionary and taxonomic questions, such as the role that introgressive hybridization might be playing as a driver of speciation in profundulid fishes. From a historical biogeographic perspective, the proposed expanded geographic range could be explained by inter-basin dispersal enabled by recent or historical events (e.g., paleodrainage connections, headwaters stream capture, floodings) in the same fashion as these have been invoked to explain distribution patterns in other Middle American freshwater fishes.

Extension of measurement range in optical correlation-domain reflectometry based on temporal gating scheme

Extension of measurement range in optical correlation-domain reflectometry based on temporal gating scheme

A confirmed range extension for the south‐eastern long‐eared bat (Nyctophilus corbeni) into the central Victorian Murray corridor

AbstractThe threatened South‐eastern Long‐eared Bat (Nyctophilus corbeni, EPBC Act 1999 Vulnerable) is an insectivorous microbat that is dependent on tree hollows for roosting. Although it is sparsely distributed throughout the Murray‐Darling Basin, its contemporary Victorian distribution was believed to be limited to a small population in semi‐arid mallee habitats in the state's North‐West. That was until a lactating female was captured in the floodplain forest in Gunbower National Park, along the Murray River in north‐central Victoria, in late 2021. In light of this new record, in an ecological setting not typically occupied by the species, we sought to (a) confirm the presence of an established population of N. corbeni at Gunbower; and (b) if present, characterize the day roosts being used. Over eight nights (73 trapnights), we captured 172 microbats, including five N. corbeni. Traps set with acoustic lures (the Autobat MK2, or a generic bat chirper) appeared to capture more bats per trapnight than those set without lures. Four individual N. corbeni were successfully radiotracked to their roosts, which were a mix of small‐diameter (19.5–36 cm DBH), typically multi‐stemmed, live, dying and dead Black Box (Eucalyptus largiflorens) and Grey Box (Eucalyptus microcarpa) trees. While day roosts do not appear to be limiting for this species in this location, further research is needed to understand what trees are being used as maternity roosts (which may be more specialized), how far up‐ and down‐stream along the Murray River this new population extends, and whether it is geographically and/or genetically connected to populations in the Victorian mallee or in New South Wales.

Long-range over-a-meter NFC link budget with distributed large-area coils

Near-field communication is considered to have a high level of hardware security protection owing to its natural short-range wireless operation, which makes a man-in-the-middle attack impossible. Here we question this statement by demonstrating a several-meter range NFC communication channel, supported by resonance-tuned large-area distributed coils. Typical NFC antenna architectures encompass multi-turn wires, forming flat resonant coils. Being several centimeters across, those devices cannot provide reliable communication between items, situated more than a fraction of a meter apart. An appealing approach to the range extension is to enlarge the coil area, thus spreading the magnetic field over larger distances. However, in this case, the overall length of folded conducting wires becomes wavelength comparable, nevertheless, the overall size of the coil remains electrically small, considering the 13.56 MHz operation frequency. Here we demonstrate several coil designs and establish a reliable NFC channel over several-meter distances. Adaptive impedance matching is implemented to maintain an energy power transfer between resonant coils, thus further extending the communication channel and making it robust to clutter. The ability for long-range NFC communication raises security concerns in sensitive contactless operations like wireless payments, prompting the need for enhanced countermeasures due to potential hardware vulnerabilities.

Flexible Constant-Power Range Extension of Self-Oscillating System for Wireless In-Flight Charging of Drones

Flexible Constant-Power Range Extension of Self-Oscillating System for Wireless In-Flight Charging of Drones

Dynamic range extension method for sinusoidal phase modulating interferometer based on in-phase component signal reconstruction

Abstract The continuous increase of the amplitude of the measured vibration will cause spectrum aliasing in the interference signal of the sinusoidal phase modulating interferometer (SPMI), thereby constraining its measurement dynamic range (DR). To address this issue, a DR extension method of SPMI based on the reconstruction of in-phase component signal is proposed. On the basis of conventional SPMI, an additional reference signal is introduced for estimating the phase modulation depth (PMD) and the major to minor axis ratio R e of the Lissajous ellipse formed by orthogonal interference signal pair and a phase demodulation algorithm named as phase generated carrier (PGC)- in-phase component signal reconstruction (ICR)- differential-and-cross-multiplying algorithm (DCM) which integrates PGC-DCM algorithm and the ICR is proposed. Initially, the PMD is regulated to approximately 1.8412 rad, ensuring that the quadrature component signal can be accurately extracted from the mixed signal of the interference and carrier signals, even in the presence of spectrum aliasing in the original interference signal. Then, the undistorted quadrature component signal is used to reconstruct an in-phase component signal with the estimated value of R e. Finally, the reconstructed in-phase component signal and quadrature component signal are normalized, and a DCM approach is applied to obtain the measured vibration. A SPMI measurement system based on Michelson interferometer structure is constructed to experimentally validate the proposed method. The experimental results demonstrate that the proposed method can effectively extend the DR of the SPMI system in the presence of spectrum aliasing. The DR of the system is increased from 97.52 dB @ 55 Hz to 102.6 dB @ 55 Hz, with the maximum measurable amplitude increasing from 7728.75 nm @ 55 Hz to 13 705.16 nm @ 55 Hz.

Correction to: Extension of the geographical range of the primary burrowing crayfish Cambarus strigosus Hobbs, 1981 (Decapoda: Astacidea: Cambaridae) in South Carolina

Correction to: Extension of the geographical range of the primary burrowing crayfish <i>Cambarus strigosus</i> Hobbs, 1981 (Decapoda: Astacidea: Cambaridae) in South Carolina

Lead-Free Perovskite Light-Emitting Diodes.

Metal halide perovskites have been identified as a promising class of materials for light-emitting applications. The development of lead-based perovskite light-emitting diodes (PeLEDs) has led to substantial improvements, with external quantum efficiencies (EQEs) now surpassing 30% and operational lifetimes comparable to those of organic LEDs (OLEDs). However, the concern over the potential toxicity of lead has motivated a search for alternative materials that are both eco-friendly and possess excellent optoelectronic properties, with lead-free perovskites emerging as a strong contender. In this review, the properties of various lead-free perovskite emitters are analyzed, with a particular emphasis on the more well-reported tin-based variants. Recent progress in enhancing device efficiencies through refined crystallization processes and the optimization of device configurations is also discussed. Additionally, the remaining challenges are examined, and propose strategies that may lead to stable device operation. Looking forward, the potential future developments for lead-free PeLEDs are considered, including the extension of spectral range, the adoption of more eco-friendly deposition techniques, and the exploration of alternative materials.

&lt;i&gt;Frullania stylifera&lt;/i&gt; (Frullaniaceae), a new addition to the liverwort flora of Canada

Frullania stylifera (R.M. Schust.) R.M. Schust. (Frullaniaceae) is newly reported for Canada. The species grows closelyappressed to the bark of trees and shrubs and was recently documented from two areas of mature forest at Buffalo Point First Nation in extreme southeastern Manitoba, Canada. These localities represent a northern range extension for the species on the continent and include two new phorophyte hosts for North America. Features used to distinguish F. stylifera from other known species of Frullania in Manitoba are provided.