Range Extension Research Articles

Clap-and-Fling Mechanism of Climbing-Flight Coccinella Septempunctata

Previous studies on the clap–fling mechanism have predominantly focused on the initial downward and forward phases of flight in miniature insects, either during hovering or forward flight. However, this study presents the first comprehensive kinematic data of Coccinella septempunctata during climbing flight. It reveals, for the first time, that a clap-and-fling mechanism occurs during the initial upward and backward phase of the hind wings’ motion. This discovery addresses the previously limited understanding of the clap-and-fling mechanism by demonstrating that, during the clap motion, the leading edges of beetle’s wings come into proximity to form a figure-eight shape before rotating around their trailing edge to open into a “V” shape. By employing numerical solutions to solve Navier–Stokes (N-S) equations, we simulated both single hind wings’ and double hind wings’ aerodynamic conditions. Our findings demonstrate that this fling mechanism not only significantly enhances the lift coefficient by approximately 9.65% but also reduces the drag coefficient by about 1.7%, indicating an extension of the applicability range of this clap-and-fling mechanism beyond minute insect flight. Consequently, these insights into insect flight mechanics deepen our understanding of their biological characteristics and inspire advancements in robotics and biomimetics.

Range extension of Blackstripe Lizardfish, Synodus nigrotaeniatus Allen, Erdmann & Peristiwady, 2017 (Actinopterygii, Aulopiformes, Synodontidae), from Jakarta Bay, Indonesia

Three specimens (194.4–203.8 mm standard lengths) of the lizardfish Synodus nigrotaeniatus Allen, Erdmann & Peristiwady, 2017, collected from Jakarta Bay, western Indonesia, represent a significant range extension for the species, which was previously known from only six specimens collected in Lembeh Strait, North Sulawesi, eastern Indonesia. Morphological comparisons with available data from the type specimens and molecular data from the mitochondrial cytochrome oxidase subunit I (COI) gene are presented. The COI sequence data show a 4% genetic difference from the related Synodus sageneus Waite, 1905.

Bats (Mammalia: Chiroptera) from two priority areas for biodiversity conservation in the Brazilian Amazon and range extension for Carollia benkeithi (Phyllostomidae)

Abstract Amazonian tropical forests host the highest bat diversity in South America. The central area Brazilian Amazon encompasses one of the largest pristine areas within this biome, where Amanã and Mamirauá Sustainable Development Reserves (SDRs) are located. These two reserves hold the status of Priority Areas for Biodiversity Conservation due to their high biological relevance. The aim of this study was to identify the bat species richness within these SDRs to minimize the Wallacean shortfall of the chiropterofauna in the Amazon. A total of 274 specimens, collected 20 years ago and housed in the mammal collection at the Museu Paraense Emílio Goeldi, were sorted and identified. They are distributed across four families, 18 genera, and 26 species: Artibeus planirostris and Carollia perspicillata were the most abundant vouchers. We identified a range extension for Carollia benkeithi and a possible new taxon for the genus Micronycteris.

New occurrences of mammals from McKay Reservoir (Hemphillian, Oregon)

Abstract Encompassing global cooling, the spread of grasslands, and biogeographic interchanges, the Hemphillian North American Land Mammal Age is an important interval for understanding the factors driving ecological and evolutionary change through time. McKay Reservoir near Pendleton, Oregon is a natural laboratory for analyses of these factors. It is remarkable for its small vertebrate fauna including rodents, bats, turtles, and lagomorphs, but also for its larger mammal fossils like camelids, rhinocerotids, canids, and felids. Despite the importance of the site, few revisions to its faunal list have been published since its original description. We expand on this description by identifying taxa not previously known from McKay Reservoir based on specimens collected during fieldwork and through reidentification of previously collected fossils. Newly identified taxa include the borophagine canid Borophagus secundus (Matthew and Cook, 1909), the camelids Megatylopus Matthew and Cook, 1909 and Pleiolama Webb and Meachen, 2004, a dromomerycid, and the equids Cormohipparion Skinner and MacFadden, 1977 and Pseudhipparion Ameghino, 1904. Specimens previously assigned to Neohipparion Gidley, 1903 and Hipparion de Christol, 1832 lack the features necessary to diagnose these genera, which are therefore removed from the site's faunal list. The presence of Borophagus secundus, Cormohipparion, and Pseudhipparion is especially important, because each occurrence represents a major geographic range extension. This refined understanding of the fauna lays the foundation for future studies of taphonomy, taxonomy, functional morphology, and paleoecology—potentially at the population, community, or ecosystem levels—at this paleobiologically significant Miocene locality.

Extension of Negative-Sequence Current Compensation Range Based on Negative- and Zero-Sequence Voltage Injection for Hybrid Cascaded STATCOM

Negative sequence voltage (NSV) injection is an effective cluster balancing control for CHB STATCOM, which has a higher capability in eliminating unbalanced active powers than zero sequence voltage (ZSV) injection. Unfortunately, NSV is employed for negative sequence current control under unbalanced current compensation applications, and only ZSV injection is used for cluster balancing, thereby seriously limiting negative sequence current compensation range (NCCR). To extend NCCR, the converter with a common DC link, called power exchange unit (PEU), is inserted into CHB to form a hybrid cascaded structure, which can freely exchange the unbalanced active powers via the common DC link. However, only ZSV injection method fails to take the advantage of this hybrid cascaded converter (HCC) to extend NCCR. In this paper, the NSV injection with a simple algorithm in dq frame is proposed for the HCC STATCOM with negative sequence current compensation. Owing to the PEU, the NSV of CHB for cluster balancing is counteracted by superposing an opposite NSV into PEU, thus transferring unbalanced active power from CHB to PEU and not affecting the negative sequence current control. Due to the limit of PEU capacity, the ZSV injection is also employed, and thus a novel cluster balancing control based on NSV and ZSV injection is proposed, based on which the NCCR is greatly extended. Finally, the proposed control is verified by the experimental results on a 400V / 7.5kvar HCC STATCOM.

TEMPUS-A microgravity electromagnetic levitation facility for parabolic flights.

During the ∼22s lasting free fall phase in an aircraft flying a parabola, the aboard installed electromagnetic levitation facility "TEMPUS" is used to investigate contactless and undisturbed of gravity induced convection thermophysical properties and microstructure formations of hot and highly reactive metal or semiconductor melts. The completely contactless handling and measurement of a liquid by the levitation technique keeps the melt free of contamination and enables the extension of the accessible sample temperature range far into the undercooled liquid state below the melting point. Additionally, the state of reduced weight during parabolic flights allows us to considerably decrease the strongly disturbing electromagnetic levitation forces acting in ground-based facilities on the suspended liquids. The present paper explains in detail the basic principle and the technical realization of the TEMPUS levitation facility and its attached measurement devices. Furthermore, it presents some typical experiments performed in TEMPUS, which also show the advantages resulting from the combination of reduced weight, electromagnetic levitation, and contactless measurement techniques. The control and data recording, as well as the planning, preparation, and operation of the TEMPUS experiments within the parabolic flight campaign, are another aspect outlined in the following.

Dynamic stress prediction for a Pump-Turbine in Low-Load Conditions: Experimental validation and phenomenological analysis

To meet the increasing demand for higher flexibility in hydropower, an operating range extension in an existing hydroelectric powerplant is considered. To this end, the dynamic flow and structural behavior of the low-head pump-turbine is investigated in turbine mode in partial load and deep partial load conditions, to evaluate the feasibility of this flexibilization due to the increased high cycle fatigue damage. In a first step, different numerical simulation approaches that combine fluid dynamics and structural dynamics are applied and compared to in-situ dynamic strain and pressure measurements on the impeller. As a result, the modelling requirements for a numerical workflow that leads to unmatched accuracy in predicting the broad-band dynamic stresses of deep partial load are identified. In a second step, the operating-point-dependent fatigue crack initiation spots are identified based on dynamic stresses. Herein, the emergence of an additional dominant critical spot near the blade leading edge is observed, which is unexpected for low-head pump turbines. Thanks to the detailed numerical flow and structural analyses, the root cause for the dynamic stress concentration is studied and the emergence of the new critical spot is understood. It turns out in deep partial load, that the main source of pressure oscillations on the impeller blade surfaces is the vortex-dominated flow detachment zone around the blade leading edge, which, in combination with the geometry of the investigated impeller, translates into the main stress oscillations. The results of this work were later used to extend the operating range of the hydroelectric powerplant from initially 25% to 100% power output to now 0% to 100%.

Redescription and a significant range extension of Rhacophorus napoensis Li, Liu, Yu & Sun, 2022 (Amphibia, Anura, Rhacophorinae) with the first record from Vietnam

The Napo Treefrog Rhacophorus napoensis was described based on five male specimens from Napo County, Baise City, Guangxi Autonomous Region, China. Herein, we report on new findings and a range extension of this species based on an examination of preserved specimens collected from Bac Giang and Nghe An provinces, Vietnam. Futhermore, molecular analyses of specimens Rhacophorus spp. previously identified as R. rhodopus that were reported in Bac Giang, Nghe An as well as Thanh Hoa, and Ha Tinh provinces based on mitochondrial DNA supported the morphological findings. The Vietnam specimens have a pairwise divergence of less than 2% from those of the type series of Rhacophorus napoensis (based on the 16s rRNA mtDNA gene). Based on the new information, we confirm the presence of R. napoensis in Vietnam and update the diagnostic characters of this species and distribution. We suggest the species should be considered as of Least Concern (LC) following the IUCN’s Red List categories. Further studies reassessing the populations of the Rhacophorus bipunctatus complex are required.

Range extension and expanded description of Micryletta hekouensis Liu, Hou, Mo & Rao, 2021 (Amphibia, Anura, Microhylidae), with comments on Micryletta of Northern Vietnam

The Paddy frog species Micryletta hekouensis was described based on only two specimens from Nanxi Village, Nanxi Town, Hekou County, Honghe Prefecture, Yunnan Province, China. Herein, we report on new findings and a range extension of this species based on a re-examination of preserved specimens deposited in Duy Tan University (DTU) and Zoological Museum of Lomonosov Moscow State University (ZMMU) collected from Vietnam. All new specimens were previously identified as Micryletta cf. inornata or M. cf. steinegeri. Molecular analyses based on mitochondrial DNA supported the morphological findings. The newly identified specimens have a pairwise divergence of only 0.7% from those of the type series of M. hekouensis, based on the 16s rRNA mtDNA gene. Based on the new information, we confirm the presence of M. hekouensis in Vietnam and update the diagnostic characters of this species and its distribution. We suggest the species should be considered as Near Threatened (NT) following the IUCN’s Red List categories. Further studies reassessing the populations of the Micryletta inornata complex in the Indochinese Region (including Vietnam, Laos, Cambodia, and Thailand) are required.

INVESTIGATION OF THE MAP WIDTH IMPROVEMENT IN A RADIALLY REDUCED DIFFUSER DESIGN CONCEPT FOR A CENTRIFUGAL COMPRESSOR

Abstract In order to reduce the compressor cost and weight, a 15% radial reduction was applied to the diffuser passage length of a high pressure ratio centrifugal compressor. The diffuser endwall was diverged to achieve an appropriate area ratio from diffuser inlet to outlet. Two different vane shapes were considered with the radially reduced diffuser passage. The first diffuser vane was a scaled version of the baseline airfoil vane shape and this was used to develop an understanding of the impact of the passage length reduction and diverging endwall. The second vane geometry was parameterized using an unconventional method derived from published literature and optimized to improve performance at DP. The radially reduced designs matched the performance of the baseline configuration. Furthermore, despite not being one of the goals, an extension of the stable operating range of 36% and 20% at the highest speed condition was achieved for the scaled and optimized designs, respectively. The current study focuses on understanding the physical reasons that generated this significant enhancement to the compressor operating range. In order to acquire the desired understanding, experimental data is presented to validate the Computational Fluid Dynamics (CFD) model and a detailed numerical investigation is presented to explain the changes in the flow field within the radially reduced designs. Detailed scrutiny of the flow field revealed a secondary flow feature in the diffuser passage which resulted in higher diffuser passage losses at DP but stabilised the flow as it developed for lower mass flow rate operating points.

Sosuga Virus Detected in Egyptian Rousette Bats (Rousettus aegyptiacus) in Sierra Leone.

Sosuga virus (SOSV), a rare human pathogenic paramyxovirus, was first discovered in 2012 when a person became ill after working in South Sudan and Uganda. During an ecological investigation, several species of bats were sampled and tested for SOSV RNA and only one species, the Egyptian rousette bat (ERBs; Rousettus aegyptiacus), tested positive. Since that time, multiple other species have been sampled and ERBs in Uganda have continued to be the only species of bat positive for SOSV infection. Subsequent studies of ERBs with SOSV demonstrated that ERBs are a competent host for SOSV and shed this infectious virus while exhibiting only minor infection-associated pathology. Following the 2014 Ebola outbreak in West Africa, surveillance efforts focused on discovering reservoirs for zoonotic pathogens resulted in the capture and testing of many bat species. Here, SOSV RNA was detected by qRT-PCR only in ERBs captured in the Moyamba District of Sierra Leone in the central region of the country. These findings represent a substantial range extension from East Africa to West Africa for SOSV, suggesting that this paramyxovirus may occur in ERB populations throughout its sub-Saharan African range.

Dual-comb interchanging absolute distance measurement with non-ambiguity range extension

We demonstrate a rapid and high-precision dual-comb ranging method with a significantly extended non-ambiguity range (NAR). By reasonably setting the polarization combining and splitting of two optical combs, we can obtain two sets of interferograms of signal comb and local oscillator comb interchanging simultaneously. This method allows us to extend the NAR to tens to hundreds of kilometers without changing the repetition rate of the signal comb. With this scheme, we demonstrate a dynamic distance measurement when a moving target crosses a measurement dead zone that is 3–4 times the NAR. The standard deviation of the residual distance is 1.48 μm with a 925 μs update rate. This rapid, high-precision, and NAR extension absolute distance measurement scheme will have broad potential in various ranging applications.

A southern range extension for Sminthopsis macroura in Western Australia, at Eucla

A southern range extension for Sminthopsis macroura in Western Australia, at Eucla

Moorish Viper, Daboia mauritanica (Gray, 1849) (Squamata, Viperidae), in Algeria: new provincial records, range extension, and an update on its distribution

 Daboia mauritanica (Gray, 1849), Moorish Viper, is native to North Africa. We update the distribution map for this species in Algeria, providing 19 new locality records, filling distribution gaps and significantly expanding the species’ known range. Our updated distribution map reveals a widespread presence of the species in northern Algeria, extending south into the northern Sahara. We note that some historical records in certain provinces remain unconfirmed and/or questionable, indicating the need for further investigation. Our findings underscore the importance of collaboration between researchers and citizen scientists in Algeria.

New records of seahorses (Teleostei: Syngnathidae: Hippocampus) from Kuwait in the Arabian (Persian) Gulf

A single species of seahorse, Hippocampus kuda, has been reported from the Arabian/Persian Gulf. Anatomical and DNA analyses of specimens from Kuwait indicate a second species occurs in the northern Gulf, and based on available specimens, may be the most prevalent species in the region. Evidence indicates the species to be H. trimaculatus and represents a range extension from India’s Gulf of Kutch of 2,600 km. DNA analysis of additional specimens is encouraged, particularly of H. trimaculatus specimens from outside the Gulf.

Searching for large dark matter clumps using the Galileo Constellation clock variations

This study presents bounds on transient variations of fundamental constants, with typical timescales ranging from minutes to months, using clocks in space. The underlying phenomenology describing such transient variations relies on models for Dark Matter (DM) which suggest possible encounters of macroscopic compact objects with the Earth, due to the motion of the solar system in the galactic halo. If such compact objects possess an effective feeble interaction with the ordinary matter beyond the gravitational one, it may result in effective transient variations of fundamental constants. Such variations leave signatures on clocks onboard GNSS satellites. In this paper, we introduce a phenomenological study dedicated to the search for such DM transient objects using the network of passive hydrogen masers (H-Masers) onboard Galileo satellites. We first model the signature of transient variations of fundamental constants as a frequency modulation in the difference between two satellite clocks, considering the satellite trajectories relative to the transient event. Then, we present first results based on a fast analysis method, the maximum reach analysis. The main result is a significant extension of the discovery range for DM transients, with a sensitivity never achieved before. We investigate indeed the range of transient sizes from 105 to 109 kilometres, which, apart from indirect and model-dependent non-transient effects, has never been explored previously.

Extension of the Control Range of Power Units: Problems and Their Solution

Extension of the Control Range of Power Units: Problems and Their Solution

New shark in the park: Tiger shark Galeocerdo cuvier observations in the remote South Pacific.

We present the first photographic records of the tiger shark (Galeocerdo cuvier) at the remote Rapa Nui (Easter Island) in the south-east Pacific. Previous anecdotal sightings exist for tiger sharks in this region; however these records have not been reported within the scientific domain. The present sighting occurred in a period of unusually warm sea surface temperature, which has been shown to influence tiger shark range extensions elsewhere. Novel and historic species occurrence records are valuable for determining and predicting species' environmental tolerances, migratory routes, and distributional limits.

First record of Hydroptila ivisa Malicky, 1972 (Trichoptera, Hydroptilidae) from the Ecoregion 6, Hellenic Western Balkans

Adult caddisfly specimens were collected from the Karadak Mountain in Kosovo along the border area with the Republic of North Macedonia during June 2020. Seven species belonging to seven caddisfly families were found. From this area, we report Hydroptila ivisa Malicky, 1972 for the first time for Kosovo and the Ecoregion 6, Hellenic Western Balkans. Range extension for Synagapetus slavorum Botosaneanu, 1960, Hydropsyche emarginata Navàs, 1923 and Polycentropus slovenica Malicky, 1998 is also reported. These findings increase the knowledge on the distribution and diversity of several rare species of caddisflies and especially of the new finding, H. ivisa in the Western Balkans and highlight the importance of further studies and conservation efforts for freshwater biodiversity in this region.

First record of Saddle Barb, Barbodes sellifer Kottelat & Lim 2021 (Cypriniformes, Cyprinidae), on Belitung, Indonesia, with an update of its geographic distribution

Saddle Barb, Barbodes sellifer, is a freshwater fish endemic to Malay Peninsula and the Indonesian archipelago and is here recorded for the first time from Belitung Island, Indonesia. This is a range extension of about 300 km to the southeast from the closest previously known locality on Bangka Island, and, in addition to reporting its occurrence on another island of the Indonesian archipelago, this is the southernmost known locality for the species. We also provide an updated map showing the species’ distribution.