{"title":"Eusociality unveiled: discovery and documentation of two new eusocial shrimp species (Caridea: Alpheidae) from the Western Indian Ocean","authors":"Hossein Ashrafi, K. Hultgren","doi":"10.3897/asp.81.e111799","DOIUrl":"https://doi.org/10.3897/asp.81.e111799","url":null,"abstract":"Abstract The alpheid snapping shrimp genus Synalpheus Spence Bate, 1888, is a prominent component of arthropod diversity found in coral reefs. Notably, Synalpheus is the only genus of marine organisms known to exhibit eusocial behavior. Although eusociality has evolved at least four times independently in Synalpheus, all described eusocial species are from the West Atlantic, with only a single study documenting possibly eusocial species from Indonesia. In 2008, during an expedition to Madagascar organized by the Florida Museum of Natural History (FLMNH), a diverse array of sponge-dwelling species was collected, including two species of Synalpheus exhibiting colonial behavior. Through detailed examination of these specimens, we have confirmed that these two species are eusocial and represent new eusocial species of Synalpheus outside of the West Atlantic. Consequently, we provide the first official documentation of eusocial species from the Western Indian Ocean and present their taxonomic descriptions and their phylogenetic relationships with other species of the genus in this study.","PeriodicalId":503536,"journal":{"name":"Arthropod Systematics & Phylogeny","volume":"214 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139145385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiao-Zhu Luo, Mariam Gabelaia, A. Faille, Rolf Beutel, Ignacio Ribera, B. Wipfler
{"title":"New insights into the evolution of the surface antennal sensory equipment in free-living and cave-dwelling beetles (Leiodidae: Leptodirini)","authors":"Xiao-Zhu Luo, Mariam Gabelaia, A. Faille, Rolf Beutel, Ignacio Ribera, B. Wipfler","doi":"10.3897/asp.81.e98166","DOIUrl":"https://doi.org/10.3897/asp.81.e98166","url":null,"abstract":"The stable environment of subterranean realms is characterized by constant darkness, temperature and humidity, and scarcity of resources. This led to similar adaptations in different lineages of animals, such as the reduction of eyes and pigmentation. It is common textbook knowledge that blindness in cave insects is compensated for by transformations of other sensorial structures, especially the antennae with their rich array of sensilla. We tested this hypothesis with 33 species of Leiodidae of the tribe Leptodirini (Coleoptera) with and without eyes and from hypogean and epigean environments. We documented and compared the number, types, arrangement and density of smooth and furrowed antennal sensilla on certain flagellomeres. Our statistical analysis that took effects of body size and phylogeny into consideration showed that (1) the number of these sensilla does not differ between hypogean or epigean beetles; (2) the same applies to length and diameter of the antennal sensilla; (3) there is a difference in density, but unexpectedly it is lower in hypogean species. Our finding thus contrasts with widely accepted earlier interpretations for those external antennal sensilla in the studied Leptodirini, showing that sensillar patterns are scarcely affected in these subterranean beetles if at all, and even less dense in blind and cave-living species. Our results thus add a new facet to the evolution of cave animals.","PeriodicalId":503536,"journal":{"name":"Arthropod Systematics & Phylogeny","volume":"295 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139152593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}