Zoological Studies最新文献

Sea anemones (Cnidaria, Actiniaria) are a successful group of marine invertebrates found in a diverse range of environments globally. In spite of their ubiquity, identities for many sea anemones remain unverified, especially those from the Indo-West Pacific region. Here, we clarify the taxonomy of the poorly known Macrodactyla aspera, a shallow-water species first described from the Torres Straits in northern Australia. We re-describe M. aspera based on new morphological and molecular data gathered from the type specimen, other museum vouchers, and from fresh material collected from Singapore. We tested the monophyly of Macrodactyla using three mitochondrial (12S, 16S and cox3) and one nuclear (28S) marker based on three congeners, recovering this genus to be polyphyletic. As a consequence, we transferred M. doreensis to the genus Heteractis, and describe a new species, Macrodactyla fautinae sp. nov. While both M. aspera and M. fautinae sp. nov. share the same arrangement and number of complete mesenteries, a similar distribution of cnidae, and are not symbiotically associated with any other biota, M. fautinae sp. nov. has perforated, lobe-like verrucae on its column, and lacks nematocyst batteries on its tentacles, unlike M. aspera. These two species also occur in similar habitats in Singapore. Finally, because M. aspera strongly resembles Dofleinia armata, the latter species flagged as a danger to public health due to its ability to inflict painful stings, we tested the relationship between these species and found them not to be closely related. However, tentacles of M. aspera, like D. armata, are densely covered with nematocyst batteries and harbour large nematocysts; we infer that M. aspera may also be capable of delivering stings that endanger public health. This study builds upon a growing number of studies that aim to ascertain identities and systematics of sea anemones historically reported from the Indo-West Pacific. Our findings will facilitate accurate species identification, which is crucial for advancing research, formulating conservation measures, and protecting public health.

The male and female genital morphologies of the tribe Aphractini are presented in this study. Four species are included: Aphractus acuminatus, Paraphractus abbreviatus, Polycleptidella chilensis and Polycleptis scutellifera. A dichotomous key to the genera is provided. The lengths between the female spermathecal duct and titillatory articulated processes are similar within species but differ between them. Therefore, we propose that the function of these organs could be associated with the sperm removal strategy.

The genus Parahubrechtia Gibson and Sundberg, 1999 was first described within the family Hubrechtiidae (class Pilidiophora) and subsequently transferred to the family Callineridae (class Palaeonemertea). Here we describe two new species, Parahubrechtia rayi sp. nov. from the Sea of Japan (Russia) and P. peri sp. nov. from the South China Sea (China). A phylogenetic analysis based on partial sequences of five nuclear and mitochondrial gene regions, 18S rRNA, 28S rRNA, histone H3, 16S rRNA, and COI, has confirmed the monophyly of the genus Parahubrechtia, and indicated a close relationship to Callinera Bergendal, 1900, whose monophyly is not confirmed. Both genera belong to the family Tubulanidae, with its junior synonym being Callineridae. Three major subclades are distinguished within the Tubulanidae: subclade Tubulanus s. str., subclade Tubulanus punctatus, and subclade Parahubrechtia + Callinera. The further status of Parahubrechtia depends on whether the paraphyly of Callinera is confirmed or not and how the problem of paraphyly of the genus Tubulanus Renier, 1804 is resolved.

Rice fields are important habitats for a variety of water birds, and their importance is increasing with the destruction of natural wetlands. This study was conducted to understand the foraging strategy of the black-faced spoonbill, an internationally endangered species, in rice fields. To achieve this objective, the feeding success rate of black-faced spoonbills in rice fields was analyzed considering the species' feeding behavior, environmental factors, and external factors. The number of sweeps per minute and number of steps per minute were evaluated as features of feeding behavior; rice field type, water level, and rice height as environmental factors; and the size of a flock and number of other species in the fields when black-faced spoonbills were feeding as external factors. The feeding success rate of the black-faced spoonbills increased as they were feeding while moving at a fast pace in a rice field with a water level of 10 cm or below, rice height of 15 cm, and without herons (competitor species). These factors may be an effective strategy to increase the probability of food acquisition by black-faced spoonbills in rice fields. Therefore, to allow black-faced spoonbills during breeding season to use the rice fields for feeding, it is necessary to maintain a water level of 15 cm or less before transplanting rice. Moreover, the use of pesticides must be minimized to increase abundance of the food resources in rice fields.

Darevskia is a particularly species-rich radiation of Palearctic rock lizards from the Caucasus region. Thanks to intense systematic and taxonomic research, the knowledge of species-level diversity within this genus has increased over the last quarter century. Here, we described a new species, Darevskia salihae sp. nov. from northeastern Turkey. The new taxon is differentiated from other nearby taxon by the low number of dorsal scales in the middle of the body, the shorter body length, and the absence of blue dots both on the lateral region above the forelimbs and on the margin of the ventral plates. In addition to their morphological differences, the new taxon is phylogenetically different from close groups. It is located in a separate subclade from the rudis-valentini-portschinskii subclade. This distinction is supported by both a high bootstrap value (100) and a high posterior probability value (1.00). These two subclades are separated from each other by a genetic distance of almost 4%. This separation is supported not only genetically and morphologically, but also geographically. Since the habitat of the new taxon is limited to a high mountain and a narrow valley, it does not provide an opportunity for a different Darevskia species to shelter because it creates geographical isolation. However, Darevskia parvula that live closest to the habitat of the new taxon live only at the habitat boundaries and do not enter areas where the new taxon is found. Therefore, it might be possible that while it was separated from the rudis-valentini-portschinskii group during the evolutionary transformation, it remained as a refuge and relict in a narrow area as a result of the collapse of the valleys and the partial uplift of the Kaçkar Mountains.

The effects of parasitic copepods on free-living hosts are infrequently documented, and the copepod Pharodes tortugensis has remained virtually unstudied since described. For the first time, we document its host range in the British Virgin Islands (BVI), the prevalence and intensity of infections on wild hosts, and its impacts on host morphology and performance. Infections were observed on four benthic gobies in the BVI (Coryphopterus glaucofraenum, C. venezuelae, C. dicrus and C. eidolon) but not on other host species previously reported from other parts of the western Atlantic. Infected gobies were widespread in the BVI (detected at 33 of 52 sites, prevalence from 1-25%) but extremely rare elsewhere in the Caribbean (detected at 2 of 16 sites, prevalence < 0.006%). As is typical of macroparasite infections, P. tortugensis was over-dispersed in BVI host populations (mean intensity = 4.7, range = 1-17). Infections were most common in juvenile and female hosts, and rarely found in larger male hosts. The copepods attach in the branchial chamber of the goby; female copepods show high attachment fidelity to the ventral surface of the chamber, while male copepods attached most often to the first two gill arches and in the branchial chamber adjacent to the female. Infections caused substantial damage to the host's branchial chamber and gill filaments. Parasitized gobies also had larger livers and smaller gonads than unparasitized individuals of similar length. The changes in organ mass of infected gobies were not sizeable enough to affect total body mass, and host condition (the body-length vs. body-mass relationship) was similar for gobies with and without infections. Parasitized gobies were, however, significantly smaller in body mass at a given age, reflecting slower overall growth. Effects of P. tortugensis on individual hosts were broadly similar to those of other parasitic copepods that infect fish gills and, for unknown reasons, the BVI appears to be a persistent hotspot of infections on these goby hosts.

Herbivory plays a fundamental role in determining the structure of savannas. The impacts of small and medium-sized mammalian herbivores on trees in savannas remain poorly understood because most research attention focuses on large herbivores such as elephants whose destructive effects on trees can be pervasive at landscape scales. On the other hand, feeding activities of generalist herbivores such as Cape porcupines on woody plants can lead to tree mortality. This study investigated the utilisation of woody plants by the Cape porcupine in three mesic savanna sites in South Africa. We determined the woody plant diet of the porcupine for the early and late dry seasons at Roodeplaat Farm in Gauteng Province, and at Goss Game Farm and Bisley Valley Nature Reserve in KwaZulu-Natal Province. Thirty and twenty randomly located quadrats (30 m × 30 m) were laid at Roodeplaat and Goss, respectively, while 10 smaller quadrats (10 m × 10 m) were laid at Bisley. We measured stem diameter and the length and width of bark scars made by porcupines on stems of woody plants. We collected ten dung samples from each study site in the wet and dry seasons for quantification of woody material in porcupine diet. Porcupine foraging behaviour impacted different tree species at each site: Vachellia robusta at Roodeplaat, Spirostachys africana at Goss and Vachellia nilotica at Bisley. Each of these trees was dominant at each site. More scarring and tree mortality were recorded at Bisley with almost 70% tree sapling mortality occurring on trees that porcupine fed on. The size of bark scars was greater at Goss (P < 0.01) than at Roodeplaat and Bisley, which were similar. The area of bark damage on S. africana trees differed significantly by stem diameter size class (P = 0.007) and was greater for small stems (size class < 7.1 cm) than the larger stems (size classes 7.1-14 cm and 14.1-21). For all the study sites, dung samples revealed that woody material contributed over 80% of the porcupine diet during the dry season, but was lower at 35% during the wet season for Roodeplaat, although it was consistently high for Bisley at 79%. Porcupine foraging activities substantially contributed to tree mortality at each site. We posit that porcupine induced mortality on dominant tree species at each site may contribute to structural heterogeneity in woody plant vegetation in mesic savannas.

Invasive ants are usually harmful taxa and are considered a potential problem to biodiversity due to their negative ecological impacts, as they can outcompete native ant species. Ten such species are reported in Brazil. In this study, we report for the first time the Asian tramp ant Technomyrmex vitiensis Mann, 1921 at the municipality of Oiapoque, in the Brazilian Amazon. The colony studied contained workers, intercastes, males and larvae, which provided sperm structure and cytogenetic data. Considering the unprecedented report of the genus Technomyrmex as well as the recent finding of the primarily Australian genus Leptomyrmex in Brazil, we present a revised key for the workers of Brazilian Dolichoderinae genera. Technomyrmex vitiensis presented 2n = 16 chromosomes; all metacentrics and comparative cytogenetics on the genus is provided. A single rDNA 18S site located in intrachromosomal region was observed in this species, which is a common trait in ants. The spermatozoa of T. vitiensis had a filiform shape, with 78.13 (± 1.96) μm of total length and 11.43 (± 0.51) μm of nucleus length. Total and nucleus sperm size length fit with the known variation observed in other ant species. The occurrence of T. vitiensis in Brazil is probably a result of traffic between French Guiana and the Amapá state. Cytogenetics and sperm structures of T. vitiensis enhance the biological knowledge of this tramp species. We highlight the scarce knowledge of ant diversity in the state of Amapá and the consequences that the presence of this species may have in this region.

The present study describes three new species of Platynereis Kinberg, 1865 from Taiwan to provide a better understanding of the diversity of Platynereis in the tropical Western Pacific. Platynereis hemeiensis sp. nov. is similar to P. abnormis (Horst, 1924), P. australis (Schmarda, 1861), P. hutchingsae de Leon-Gonzalez, Solis-Weiss and Valadez Rocha, 2001, and P. sinica Sun, Shen and Wu, 1978 in terms of having no notopodial homogomph falcigers in adults. However, P. hemeiensis sp. nov. differs from P. australis by having: 1) fewer transverse rows or diagonal lines in Areas III, IV, VI and VII-VIII (2-3, 6-8, 2 and 2 versus 5, 10, 4 and 4, respectively); 2) tapered dorsal cirri on anterior-most chaetigers (versus stout dorsal cirri); and 3) dorsal cirri always shorter than dorsal ligule in posterior chaetigers (versus always longer than dorsal ligule). Platynereis hemeiensis sp. nov. can be distinguished from P. abnormis and P. sinica by having transverse rows of pectinate paragnaths in Area III (versus no pectinate paragnaths). Platynereis hemeiensis sp. nov. can be readily differentiated from P. hutchingsae by having long-bladed heterogomph spinigers in neuropodia (versus short-bladed heterogomph spinigers). Both P. jihueiensis sp. nov. and P. shihmenensis sp. nov. are somewhat similar to P. bicanaliculata (Baird, 1863), because all have bifid tip of notopodial anchylosed falcigers. However, the two species differ from P. bicanaliculata by having either no pectinate paragnaths or rows of pectinate paragnaths in Area III (versus a broad, oval patch of pectinate paragnaths). Platynereis jihueiensis sp. nov. differs from P. shihmenensis sp. nov. by having: 1) three groups of pectinate paragnaths in Area III (versus no pectinate paragnaths); 2) six to seven transverse rows of pectinate paragnaths in Area IV (versus four transverse rows); 3) three parallel transverse rows of pectinate paragnaths in Area VI (versus three to four non-parallel rows); 4) seven groups of transverse rows of pectinate paragnaths in Areas VII-VIII, middle groups each with three rows and two outer most groups each with one and two paragnaths (versus five groups of transverse rows of pectinate paragnaths, middle groups each with 1-2 rows and two outer most groups each with one paragnath); and 5) each parapodium of chaetigers in anterior, mid-body and posterior regions with three, two and one notopodial homogomph falcigers, respectively (versus each parapodium with one notopodial homogomph falciger in all body regions). A key for identifying Platynereis species from East Asia is provided.

The genus Lewisister Bickhardt, 1912 was previously only known to contain a single species, L. excellens Bickhardt, 1912, and had only been recorded from Southeast Asia. In this study, a new species found in Taiwan, L. masumotoi sp. nov., is described and the male genitalia are illustrated. Additional morphological characters are presented for L. excellens Bickhardt, 1912 and an illustration of its male genitalia is provided. The pairwise genetic distance of COI sequences of Lewisister are also provided to support the delimitation of both species. Both species are distributed in Taiwan, and the distribution records from Taiwan are discussed.