{"title":"Unveiling the Diversity of the Semislug Genus <i>Durgella</i> Blanford, 1863 (Eupulmonata: Helicarionidae) from Thailand and Myanmar, with Description of Two New Species.","authors":"Arthit Pholyotha, Chirasak Sutcharit, Ngwe Lwin, Somsak Panha","doi":"10.6620/ZS.2024.63-14","DOIUrl":"https://doi.org/10.6620/ZS.2024.63-14","url":null,"abstract":"<p><p><i>Durgella</i> is a terrestrial semislug genus in the family Helicarionidae and currently comprises nine species recorded from Thailand and Myanmar. Two species, <i>D. concinna</i> and <i>D. rhaphiellus</i>, have been described based only on shell information, while the taxonomy of the remaining seven species is comprehensively treated herein using comparative morphology. Revised species descriptions are given for <i>D. levicula</i>, <i>D. erratica</i>, <i>D. siamensis</i>, and <i>D. libas</i>; <i>D. birmanica</i> (previously placed in the <i>Megaustenia</i>) is moved to this genus; and two species, <i>D. pentata</i> Pholyotha & Panha, sp. nov. and <i>D. nulla</i> Pholyotha & Panha, sp. nov., are described as new to science. Based on our findings, the combination of shell characters including shape, size, aperture, and umbilicus; the number of mantle extensions; and the genitalia, especially the penis, epiphallus, and dart apparatus, can be used to distinguish these nine species. Among these nine recognised species, only <i>D. nulla</i> Pholyotha & Panha, sp. nov. has no dart apparatus.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e14"},"PeriodicalIF":1.5,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11609696/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142774066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoological StudiesPub Date : 2024-05-14eCollection Date: 2024-01-01DOI: 10.6620/ZS.2024.63-12
Jessica M Legaspi, Annabelle G C Del Norte-Campos, Wilfredo L Campos
{"title":"Age and Growth of the Indian Squid, <i>Uroteuthis duvaucelii</i>: Analysis of Statolith Microstructure and Length Frequency Data.","authors":"Jessica M Legaspi, Annabelle G C Del Norte-Campos, Wilfredo L Campos","doi":"10.6620/ZS.2024.63-12","DOIUrl":"https://doi.org/10.6620/ZS.2024.63-12","url":null,"abstract":"<p><p>Understanding the age and development of a species provides knowledge about its longevity and growth, which are crucial in assessing its life history to maintain the sustainability of its fisheries. Over 3000 samples of <i>Uroteuthis duvaucelii</i> were collected from trawl catches off Concepcion, Iloilo, Western Visayas, Philippines, from April 2018 to September 2019. Daily rings in the statoliths were used to determine their age. The estimated age ranged from 73 to 154 days old, corresponding to sizes of 3.1 to 28.1 cm mantle length. The presence of small individuals (~4 cm) throughout the year indicate continuous spawning of this species. Growth curve patterns of <i>U. duvaucelii</i> were examined using two techniques: growth from sizeat-age data (statolith increments) and growth generated from length-frequency data using the ELEFAN software package. Both methods yielded results that were remarkably different from one another. The growth curve generated from length frequency analysis produced an asymptotic growth. In contrast, sizeat-age data (mantle length-age relationship) revealed that <i>U. duvaucelii</i> does not grow asymptotically. The growth of this tropical squid is best fitted with exponential growth, exhibiting a continuous rapid growth and short lifespan, a prominent characteristic observed in neritic species of squids. This work provides evidence that asymptotic growth is not applicable for the tropical squid species in the Visayan Sea, Philippines.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e12"},"PeriodicalIF":1.5,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11609533/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142774013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoological StudiesPub Date : 2024-05-14eCollection Date: 2024-01-01DOI: 10.6620/ZS.2024.63-05
Hong Chen, Fenghua Zhang, Lei Yang, Zaixin Li, Jiajie Liu
{"title":"Changes in Soil Bacterial and Nematode Communities during Long-term Continuous Cotton Cropping in an Arid Region.","authors":"Hong Chen, Fenghua Zhang, Lei Yang, Zaixin Li, Jiajie Liu","doi":"10.6620/ZS.2024.63-05","DOIUrl":"10.6620/ZS.2024.63-05","url":null,"abstract":"<p><p>larifying the effects of continuous cotton cropping (CC) on soil biological communities is essential for maintaining agricultural productivity. In this study, high-throughput sequencing was used to study the effects of different CC durations (0-yr, 5-yr, 10-yr, 15-yr, 20-yr, and 25-yr CC treatments) on soil microbial and nematode communities. The results showed that the dominant bacterial phyla were Actinobacteria and Proteobacteria, and the dominant nematode genus was <i>Helicotylenchus</i> in all CC treatments. The richness indexes (ACE and Chao1 index) and diversity index (Shannon index) of bacterial and nematode communities were the highest in the 15-yr and 10-yr CC treatments, respectively. Bacterial community was significantly correlated with soil pH and available potassium (AK), and nematode abundance was significantly correlated with microbial biomass carbon (MBC). Soil bacterial PICRUSt analysis results showed that carbon metabolism and amino acid metabolism were the main metabolic functions of bacteria in the CC treatments. The composition and diversity of soil nematode communities were significantly related to the structure of soil bacterial communities, and the niche breadth of soil bacteria was negatively correlated with that of nematodes. <i>Panagrolaimus</i> and <i>Acrobeles</i> were the main genera of bacterialfeeding nematodes affecting bacterial communities, and their relative abundances were significantly positively correlated with the relative abundance of bacterial communities. Overall, long-term (10-15 years) continuous cotton cropping negatively impacts soil biota and the microecological environment of cotton fields in arid regions.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e5"},"PeriodicalIF":1.5,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11443426/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142362410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoological StudiesPub Date : 2024-05-14eCollection Date: 2024-01-01DOI: 10.6620/ZS.2024.63-11
Suphatsara Sangphueak, Tin Yan Hui, Sarah L Y Lau, Gray A Williams, Kringpaka Wangkulangkul
{"title":"Habitat Partitioning in Two Intertidal Limpets, <i>Siphonaria guamensis</i> (Heterobranchia) and <i>Patelloida saccharina</i> (Patellogastropoda), from Southern Thailand.","authors":"Suphatsara Sangphueak, Tin Yan Hui, Sarah L Y Lau, Gray A Williams, Kringpaka Wangkulangkul","doi":"10.6620/ZS.2024.63-11","DOIUrl":"10.6620/ZS.2024.63-11","url":null,"abstract":"<p><p>Mobile intertidal animals exhibit various strategies during emersion to mediate the impact of heat and desiccation, including behavioural adaptations such as moving to lower tidal levels and seeking thermal refuges, which can result in spatial partitioning between species within the intertidal environment. We tested whether the limpets <i>Siphonaria guamensis</i> (Heterobranchia) and <i>Patelloida saccharina</i> (Patellogastropoda) exhibited differential habitat use during tidal emersion by quantifying their abundance and size distribution in various habitats on two rocky shores on the west coast of Thailand. <i>S. guamensis</i> inhabited higher shore levels with hotter average rock temperatures when emersed as compared to <i>P. saccharina</i>. On one of the shores, large <i>S. guamensis</i> lived at higher tidal levels than smaller individuals, whereas large <i>P. saccharina</i> showed the reverse pattern, being found lower on the shore than smaller individuals. The abundance of <i>S. guamensis</i> was positively correlated to the shore slope, with more individuals found on vertical than horizontal rocks, while <i>P. saccharina</i> showed a negative relationship between abundance and algal cover. At the heights where they were most abundant, both species were more often found in bare rock habitats as opposed to crevices and areas dominated by oyster shells, despite the fact that bare rock was as hot as or even hotter than other microhabitats. The exact resting locations of the two species were, however, cooler than the mean temperature of the bare rock. In general, limpets did not exhibit a strong preference for any particular rock orientation, but <i>S. guamensis</i> on one shore was more abundant on east-facing rocks as compared to other aspects. As a result, although thermal stress appears to be a driver for habitat partitioning between species (occupying different tidal heights), temperature alone is unable to explain distribution patterns within species, as limpets were not adopting thermal refuges during tidal emersion. Variations in the physical environments may be mediated by species-specific morphological and/or physiological adaptations which determine the distribution of different limpet species on western Thailand rocky shores.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e11"},"PeriodicalIF":1.5,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11629110/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142808439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoological StudiesPub Date : 2024-05-03eCollection Date: 2024-01-01DOI: 10.6620/ZS.2024.63-09
Charo López-Blanco, Ohrideja Tasevska, Goce Kostoski, Eduardo Vicente, Laura S Epp, Antonio García-Alix
{"title":"Ancient Endemic or Recent Invader? Phylogenetic Position and the Probable Origin of the Ccladoceran <i>Diaphanosoma macedonicum</i> (Diplostraca, Sididae) from the Ancient Lakes in the Balkans.","authors":"Charo López-Blanco, Ohrideja Tasevska, Goce Kostoski, Eduardo Vicente, Laura S Epp, Antonio García-Alix","doi":"10.6620/ZS.2024.63-09","DOIUrl":"10.6620/ZS.2024.63-09","url":null,"abstract":"<p><p>Ancient lakes contain unique and very vulnerable fauna. Determining and understanding the origin of such biodiversity is a key factor in promoting conservation and management actions in some of the most singular ecosystems on the planet. Lake Ohrid in the Balkans is known as a natural laboratory for speciation, containing a high number of endemic species. However, the identity and origin of the planktonic cladoceran <i>Diaphanosoma</i> is uncertain. Representatives of the genus were long considered to have invaded the lake, but recent morphological studies have suggested that they belonged to the endemic taxon in the Balkans, <i>D. macedonicum</i>. Here, phylogenetic methods based on two mitochondrial gene fragments (<i>COI</i> and 16S) were used to identify <i>Diaphanosoma</i> specimens from the ancient Lake Ohrid and Lake Prespa in the Balkans and compare them with other species in Europe, including those living in nearby water bodies. Molecular evidence showed that <i>D. macedonicum</i> was constrained to the ancient lakes Ohrid, Prespa, and Mikri Prespa, which suggests reproductive isolation within the lakes. Phylogenetic analyses supported previous morphological assessments and situated <i>D. macedonicum</i> within the <i>D. mongolianum</i> species group, which contains three sibling species (<i>D. mongolianum</i>, <i>D. lacustris</i>, and <i>D. macedonicum</i>). Nuclear markers are needed to study intraspecific gene flow in these organisms and discard a potential formation of hybrids.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e9"},"PeriodicalIF":1.5,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11561547/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142631345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoological StudiesPub Date : 2024-04-16eCollection Date: 2024-01-01DOI: 10.6620/ZS.2024.63-07
Filipe Macedo Gudin, Diego Galvão de Pádua, Pablo Ricardo Mulieri, Benito Cortés-Rivas, Andrés Moreira-Muñoz, Rodrigo de Oliveira Araujo
{"title":"Revising Spider Egg-predating Fly Records (Diptera: Sarcophagidae): New Insights on Prey, Taxonomy, and Distribution of <i>Sarcophaga</i> (<i>Mehria</i>) <i>lorosa</i> Hall in Southern South America.","authors":"Filipe Macedo Gudin, Diego Galvão de Pádua, Pablo Ricardo Mulieri, Benito Cortés-Rivas, Andrés Moreira-Muñoz, Rodrigo de Oliveira Araujo","doi":"10.6620/ZS.2024.63-07","DOIUrl":"10.6620/ZS.2024.63-07","url":null,"abstract":"<p><p>Flesh flies (Diptera: Sarcophagidae) exhibit a wide range of feeding habits including necrophagy, coprophagy, kleptoparasitism, parasitism, and predation. Among them are species of <i>Sarcophaga</i> Meigen belonging to the subgenera <i>Baranovisca</i> Lopes and <i>Mehria</i> Enderlein that are specialized predators of spider eggs. These flies hover around spider webs and lay their larvae on the spider egg sac. While progress has been made on the taxonomy of <i>Baranovisca</i> and <i>Mehria</i> in recent decades, our knowledge about their biology, prey selection, and distribution remains limited, restricting our understanding of the evolutionary dynamics of Sarcophagidae-Araneae interactions. Here, we describe and illustrate the first record of <i>S</i>. (<i>M</i>.) <i>lorosa</i> Hall preying on egg sacs of <i>Metepeira galatheae</i> (Thorell) (Araneae: Araneidae) in Chile. The taxonomy of <i>S</i>. (<i>M</i>.) <i>lorosa</i> is revised, with two new junior synonyms proposed: <i>Weyrauchimyia ruficauda</i> Lopes and Tibana, syn. nov., and <i>Arachnidomyia travassosi</i> Tibana and Mello, syn. nov. Furthermore, we present an annotated catalog that comprehensively reviews the existing records of spider egg-predating Sarcophagidae, and provide an overview of the evolution of Sarcophagidae-Araneae interactions. Our catalog includes information on at least four species of <i>Baranovisca</i> and 10 species of <i>Mehria</i> that have been documented as preying on eggs from species of various spider families, such as Araneidae, Cheiracanthiidae, Clubionidae, Philodromidae, Salticidae, and Tetragnathidae. These records cover all biogeographical regions except the Afrotropical. Our results enhance our understanding of the evolution of Sarcophagidae-Araneae interactions.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e7"},"PeriodicalIF":1.5,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11561545/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142636187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoological StudiesPub Date : 2024-04-16eCollection Date: 2024-01-01DOI: 10.6620/ZS.2024.63-10
Edwin R Ariza-Marín, Larry Jiménez-Ferbans, Pedro Reyes-Castillo
{"title":"Wing Condition and Distribution of a Mesoamerican Montane Genus of Wooddegrading Beetles, <i>Oileus</i> Kaup (Coleoptera: Passalidae), with the Description of a New Species.","authors":"Edwin R Ariza-Marín, Larry Jiménez-Ferbans, Pedro Reyes-Castillo","doi":"10.6620/ZS.2024.63-10","DOIUrl":"10.6620/ZS.2024.63-10","url":null,"abstract":"<p><p>Distribution areas, in terms of size and shape, are usually related to dispersal capacity, and the latter is partly related to flight capacity in insects. Thus, wing condition (brachypterous or macropterous) is expected to correlate with the area size of the species distribution range. Here, we studied this aspect for the first time in Passalidae, a subsocial group of saproxylophagous beetles. To obtain the geographic distribution of species, we performed species distribution models in the Mesoamerican genus <i>Oileus</i>, which has seven species (including one new species from Oaxaca, Mexico) restricted to either side (west or east) of the Isthmus of Tehuantepec (except for <i>Oileus rimator</i> which is distributed in both sides of the Isthmus). Species distribution models were used to estimate biogeographic affinities among species and to compare the potential distributional area with respect to the species wing condition (four brachypterous and three macropterous). Additionally, we described the sound-emitting structures (<i>plectrum</i>, region located on hind wings) for all <i>Oileus</i>, being the first study describing it for all species of the same genus. Macropterous species tend to have larger potential distribution areas (between 149,027-364,107 km<sup>2</sup>) than brachypterous species (9,063-15,716 km<sup>2</sup>), and all brachypterous species inhabit montane areas. These results coincide with what would be expected if the loss of flight capacity reduced dispersal capacity. However, because of the limited data, we could not statistically test this relationship. Future analyses should evaluate the relationship between passalid species distributions (total area and elevation) and wing morphology, including species with narrow and wide distributions, both altitudinally and latitudinally.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e10"},"PeriodicalIF":1.5,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11561544/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142631348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Lethal Consequences and Embryo Shell Shape Alterations in the Marine Gastropod <i>Trophon geversianus</i> Due to Elevated Temperatures.","authors":"Rocío Aimé Nieto, Sebastián Giulianelli, Soledad Zabala, Gregorio Bigatti, Federico Márquez","doi":"10.6620/ZS.2024.63-08","DOIUrl":"10.6620/ZS.2024.63-08","url":null,"abstract":"<p><p>Environmental temperature is increasing while natural populations are forced to adjust their life cycle to new conditions, resulting in the expression of new phenotypic traits. Still, the links between these new environmental conditions and the subsequent phenotypic expressions are not fully explored. Here, we conducted manipulative experiments with embryos of the marine gastropod <i>Trophon geversianus</i> to assess the effects of warmer temperatures upon shell form. We observed lethal effects together with alterations in the shell form (size + shape) of embryos exposed to 18°C water compared to the control temperature environment (13°C). Our results reveal that <i>T. geversianus</i> from Patagonian coasts growing under warm temperatures will change their phenotype by developing smaller and more elongated shells during ontogeny, as well as an expanded shell aperture, increasing their predation vulnerability. Therefore, we consider that the embryonic shell shape change could be a good biomarker of thermal stress produced at early developmental stages in marine gastropods.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e8"},"PeriodicalIF":1.5,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11561543/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142631347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoological StudiesPub Date : 2024-04-16eCollection Date: 2024-01-01DOI: 10.6620/ZS.2024.63-06
Marcin Polak, Jolanta Polak
{"title":"Effects of Road-traffic Disturbances on the Bird Community of a Subtropical Island.","authors":"Marcin Polak, Jolanta Polak","doi":"10.6620/ZS.2024.63-06","DOIUrl":"10.6620/ZS.2024.63-06","url":null,"abstract":"<p><p>The rapid expansion of road networks worldwide is one of the most serious threats to biodiversity conservation. Evaluating the effects of various anthropogenic factors on the distribution and abundance of birds in subtropical and tropical ecosystems is extremely important in the context of the dynamic developments that these areas have been subject to in recent years. This study assessed the impact of road traffic on the abundance and species richness of roadside birds on the subtropical island of Tenerife. The effect of road traffic on birds was assessed at 162 observation points located in different places on the island by use of the point-count method. During the counts, a total of 765 individuals from 35 species were recorded. The number of avian species was lower in the vicinity of roadsides. Seven of the 17 most numerous birds clearly avoided the vicinity of roads, but another seven actually preferred roadside habitats; three species were neutral in this respect. The assemblage of traffic-sensitive birds consisted of specialised and endemic species, mainly inhabiting endangered native habitats such as laurel and pine forests.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e6"},"PeriodicalIF":1.5,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11561546/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142631346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zoological StudiesPub Date : 2024-03-15eCollection Date: 2024-01-01DOI: 10.6620/ZS.2024.63-04
Sam King Fung Yiu, Thomas Ka Leung, Gabriel Yeung Lee, Meng Yan
{"title":"Morphology and Phylogenetic Position of the Sargassum Nudibranch <i>Scyllaea fulva</i> Quoy & Gaimard, 1824 (Nudibranchia: Scyllaeidae): First Record in Hong Kong.","authors":"Sam King Fung Yiu, Thomas Ka Leung, Gabriel Yeung Lee, Meng Yan","doi":"10.6620/ZS.2024.63-04","DOIUrl":"10.6620/ZS.2024.63-04","url":null,"abstract":"<p><p>Scyllaeidae is a small group of nudibranchs comprising three genera (<i>Scyllaea</i>, <i>Notobryon</i>, and <i>Crosslandia</i>) with striking morphological similarities, making their identification challenging based on external features alone. Previous studies have highlighted the significance of central radular teeth in distinguishing <i>Notobryon</i> from <i>Scyllaea</i> and <i>Crosslandia</i>. The genus <i>Scyllaea</i>, commonly known as the sargassum nudibranch, currently consists of only two valid species, <i>Scyllaea pelagica</i> and <i>Scyllaea fulva</i>. These species inhabit seaweed <i>Sargassum</i> spp., feeding on hydroids. During a biodiversity survey conducted in April 2023, seven sargassum nudibranch individuals were collected from the seaweed <i>Sargassum</i> spp. at a depth of 2 meters in Tai She Wan through SCUBA diving. Initially, the specimens were misidentified based on their resemblance to <i>Notobryon wardi</i> and previous local records. However, thorough morphological and molecular examinations confirmed them to be <i>Scyllaea fulva</i>, representing the first record of this species in Hong Kong. Notably, our specimens lacked the blue spots observed in specimens from Thailand and the West Pacific Ocean, as reported in previous studies. Internally, a pineapple-like structure formed a honeycomb pattern on the surface of the masticatory edge of the jaw flap, with the presence of central radular teeth. A Maximum Likelihood tree analysis revealed <i>Crosslandia</i> to be the sister group of <i>Scyllaea</i>. Comparative analysis of intra-specific distances between individuals from the Philippines, French Polynesia, and Hong Kong indicated a close relationship between the Hong Kong specimens and those from the Philippines. Furthermore, we provide a detailed description of the external and internal morphology of <i>Scyllaea fulva</i> in this paper, integrating valuable morphological information for future species identification purposes.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"62 ","pages":"e4"},"PeriodicalIF":1.5,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11443427/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142362411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}