Zoological Studies最新文献

King cobra (Ophiophagus hannah) is a snake widely distributed through southeastern tropical Asia, but in two separate subpopulations: one located in the Western Ghats (western Indian Peninsula) and the other much more extensive, ranging between the southern slopes of the Himalayas, Assam, Indochina to southeastern China. Similarly, it also appears in numerous tropical archipelagos such as Indonesia, the Philippines, and the Andaman Islands, but surprisingly it is absent from other large islands like Sri Lanka and Taiwan. In this study, we evaluated how climate could be shaping the distribution of this snake and estimated the future distribution of the species utilizing ecological niche modelling. To evaluate the effect of paleoclimatic conditions on the genetic structure of this species we performed Bayesian phylogenetic analysis under a molecular clock using mitochondrial DNA. Our analyses indicated that the current distribution of O. hannah is strongly influenced by the availability of humid climate conditions. King cobras have a long evolutionary history reflected in the appearance of four main mitochondrial lineages before the Pliocene (the Western Ghats, southeastern mainland Asia, Luzon, and Indonesia), congruently with paleoclimatic models that indicated the availability of suitable conditions for this species in these refugia during the glacial cycles. Climate history could explain the absence of O. hannah in Sri Lanka and Taiwan due to the absence of suitable climatic corridors when these islands were connected to the mainland (20,000 years ago). Future projections (2050‒2070) did not suggest significant range shifts in the region, even considering the worst global warming scenarios.

Elpidium species exclusively inhabiting confined and temporary environments, such as those of tank-bromeliads, are a source of interesting and diverse studies on taxonomy, evolution and ecology, to name a few. However, despite its great diversity of species or potential for study, this genus (and other phytotelm members) has been poorly studied. In the last years, however, description of Elpidium species increased from six before 2013 to 11 today. This study is an effort to keep uncovering its great diversity and to go further in order to deeply understand the genus Elpidium. To this end, this study describes another species in the genus, Elpidium litoreum sp. nov., and proposes a phylogenetic reconstruction of it based on morphological characters. Our results point to the monophyly of Elpidium and puts Intrepidocythere ibipora as its sister-group. Although the phylogeny revealed some interesting relations, it also exposed some incongruities that ultimately demonstrate how superficial the current knowledge about the genus is. All these questions are discussed in detail. We see this work as at the same time an effort to better understand Elpidium and a stimulus to other researches to turn their attention to the historically neglected phytotelmata community.

Species biodiversity organises along elevational trends and is generally expected to decrease with increasing elevation. This pattern is regulated by numerous factors, although principally overridden by temperature in ectotherms such as amphibians. Here, we collated elevation data (n = 55,182) collected between 1909 and 2020. We then determined elevation distribution patterns and species communities for all amphibians in the Republic of Korea. Species were found to range from sea level up to 1,393 m a.s.l. The average elevational distribution was significantly different between species but also between anura and caudata. On average, anura were found at lower elevations with a peak in species richness and abundance matching with the lowlands. In opposition, the peak in species richness and abundance for caudata matched with low hilly landscapes. The altitudinal distributions of species were strongly skewed, with all 23 species found within the 0-199 m range, and steadily decreasing with only five species within the last elevational range (1,200-1,399 m). Finally, only a few species were found below 30 m, reflecting a likely risk of salinisation in this environment. Our results help understand the altitudinal distribution of amphibians in the Republic of Korea.

Social insects have evolved different search strategies to find target objects in unknown environments. In the present study, the searching behavior of the tropical fire ant Solenopsis geminata was investigated in a circular arena. The average time, search path, speed, and search patterns of worker ants in a circular arena were determined. The results showed that fire ant workers followed six major search patterns. The variation in the searching patterns of workers may explain the different levels of exploration. Most workers (56.8%) tended to search in small loops and progressively increase the search area size. These workers mostly turned in one direction, either clockwise or counterclockwise. More workers turned in a consistent pattern than in an inconsistent pattern. Moving speed was also higher in workers that maintained their turning directions than in those that changed directions. We thus propose that following search patterns consisting of loops of increasing size may be an effective strategy. The tropical fire ant S. geminata is a globally invasive species that was introduced to Taiwan 40 years ago and has continued to threaten residents. Based on behavioral studies of S. geminata, we may gain a better understanding of their exploratory behavior in the ecosystem in Taiwan.

Pseudoscorpions are predatory microarthropods that feed on even smaller animals, such as mites and springtails. While these organisms are generally considered terrestrial and live in the leaf litter or under barks or rocks, some pseudoscorpions live in the intertidal area, including species in the genera Anagarypus, Anchigarypus, and Garypus in the family Garypidae. This study describes two new species of the genus Garypus L. Koch from Southern Taiwan, Garypus wilsoni Lin & Chang sp. nov. and Garypus sanasai Lin, Huang & Chang sp. nov., reviews the pseudoscorpion fauna of Taiwan, and provides an updated checklist of the country. Specimens of the two new species were collected in seashore habitats and their status as new species were supported by both morphology and molecular phylogenetic analysis. Our discovery marks the first new species of pseudoscorpions reported in Taiwan since 1937, as well as the first records of the family Garypidae in Taiwan and of Garypus in East Asia. Moreover, the discovery of these two new species in Taiwan fills the regional distribution gap between Garypus in Thailand and southward and its closely related genus Anchigarypus in South Korea and Japan. The location where Garypus sanasai Lin, Huang & Chang sp. nov. was found also represents the northernmost distribution of the genus Garypus in the West Pacific.

Animals that colonize soil show specific adaptations to soil. Compared to closely related species living on the surface, the limbs of soil-dwelling animals are often shortened, reduced, or absent to allow a less restricted passage through cavities between soil particles. This pattern of limb reduction has also been observed in tardigrades, where multiple lineages that colonized the below-ground habitat show independent reduction and/or loss of legs and claws. In the tardigrade superfamily Macrobiotoidea, leg and claw reductions are a common trait found in the Macrobiotus pseudohufelandi complex. This rarely found species complex currently contains four nominal taxa. Here we describe, with the use of integrative taxonomy, Macrobiotus naginae sp. nov., a new species in the Macrobiotus pseudohufelandi complex from inland sand dunes in Finland. We also provide a dichotomous key to the Macrobiotus pseudohufelandi complex to assist with their identification in future studies.

Deep-sea hydrothermal vents are dynamic environments with exotic fauna, including bathymodiolin mussels and scale worm annelids that are often in close association. In this study, we found a new species of Branchipolynoe (Aphroditiformia: Polynoidae) living in the recently discovered mussel Gigantidas vrijenhoeki in deep-sea hydrothermal vents and methane seeps at 2,014-2,023 m depth. Based on the morphology and full mitochondrial genome sequences of specimens of Branchipolynoe from the Onnuri vent field (OVF) on the northern Central Indian Ridge, we describe them as a new species: Branchipolynoe onnuriensis sp. nov. This species resembles B. longqiensis and B. tjiasmantoi, but can be distinguished from these species by the shape of the notopodial acicular lobe and the tips of the subacicular neurochaetae. This identity is well-supported by genetic distance and phylogenetic analyses based on the mitochondrial c oxidase subunit I (COI) gene, with the new species being closest to the Western Pacific species B. tjiasmantoi. Phylogenetic analyses support close relationships between the Indian Ocean and Western Pacific hydrothermal polychaetes. Our data provide a foundation for exploring the evolutionary relationship between scale worms and bathymodiolin mussels.

This study presents a new species of free-living marine nematode, Ptycholaimellus luoyang sp. nov., from mangrove wetlands in China. The identification was confirmed by analyzing morphological characteristics and three genes: COI, 18S rDNA, and 28S rDNA. This species is distinguished from allied species by its short cephalic setae, cylindrical pharynx with anterior swelling, sclerotized transverse ridges occurring near the dorsal tooth, rod-like gubernaculum and proximal, arch-like, slightly waved, middle curved, and distally pointed spicules. The Bayesian topology was regarded as morphological evidence of P. luoyang sp. nov. being a distinct species. Interspecific and intrageneric thresholds of the K2P distance divergence have been presented here for the first time.

The bark-stripping behavior of Formosan sambar, Rusa unicolor swinhoii, has become conspicuous in recent years in the Tataka area of Yushan National Park in Taiwan and a cause for concern to visitors and ecologists. We conducted a monthly survey of 537 tagged trees of 21 species and monitored the abundance of sambar using camera traps from October 2018 to January 2021, aiming to interpret possible causes of the bark-stripping behavior in Tataka. We also used a generalized linear model to evaluate factors that may affect the probability of a tree having its bark stripped. Both our observations and the model predictions showed that sambar has a strong preference for bark of Pinus armandii, Photinia niitakayamensis, and Salix fulvopubeseens and for trees with diameter at breast height around 14 cm. Bark stripping mainly occurred between July and October when major forage was most abundant. However, sambar's need for bark surged in May when sambar abundance was moderate and decreased in October when sambar abundance was high. The seasonality of bark stripping was synchronized with the peak periods of antler development, fawn nursing, and spread of gastrointestinal parasites, suggesting that sambar strips bark to ingest minerals for their physiological needs and/or to acquire plant secondary metabolites to repel gastrointestinal parasites. Sambar abundance alone was not sufficient to predict the overall intensity of bark stripping. Rather, the product of sambar abundance and the necessity index (average wound size) were strongly correlated with the overall bark-stripping intensity. Therefore, controlling sambar abundance is essential but it alone may not be the optimal strategy for controlling bark stripping. A combination of population control and relaxing of sambar's parasite loading and/or physiological needs for minerals is an important strategy to control the overall bark stripping. Future research could use the necessity index to investigate the synchronicity of the bark-stripping behavior, deer's physiological state, environmental factors and phenology to better understand the cause of this behavior.