Diversity of Platyhelminthes Proseriata in Western Mediterranean sandy beaches: a database of species occurrences and traits

Abstract

We present here a first comprehensive database on the diversity of proseriate flatworms (Platyhelminthes: Rhabditophora: Proseriata) on Western Mediterranean microtidal, wave dominated beaches. We sampled 116 stations in two years, through Spain (22 beaches, including Balearic Islands), France (25 beaches, including Corsica), Italy (63 beaches, including Sardinia, Sicily, and Lampedusa), and Tunisia (6 beaches). In each beach, we sampled at three depths, corresponding to the swash, shoal, and subtidal zones. For each sample, we obtained environmental data. The research yielded a total of 152 species, of which 93 were new to science. For each of the species found, we coded and described 16 functional traits. We discuss the functional meaning of the selected traits, as well as on diversity patterns and emerging biogeographic signals across the investigated regions. We particularly focused on the most widespread and dominant species in our dataset, concentrating on their putative adaptations to high energy environments; as well as the high number (58) of the species only found once. Finally, we discussed the coverage of our sampling by estimating the diversity at each investigated region and comparing it to the actual diversity. All information provided is available through the Global Biodiversity Information Facility (GBIF) and the Open Science Framework (OSF) following the Darwin Core Standard.

Enhancing metabarcoding efficiency and ecological insights through integrated taxonomy and DNA reference barcoding: a case study on beach meiofauna

“…Our study emphasises the need for continuous efforts in combining traditional taxonomic identification and DNA barcoding, especially targeting under-represented regions and taxa, as the lack of taxonomic expertise and sampling leaves many beach meiofauna species undescribed (Martinez et al, 2023)(Curini-Galletti et al, 2012, 2023; Martínez et al, 2019). This hampers more detailed ecological studies that would facilitate the understanding of beach biodiversity and ecosystem processes, a task urgently needed due to increasing pressure on the globally important ecosystems (Lansu et al, 2024; Schlacher et al, 2007).…”

First record of a proseriate flatworm predating on a rhabdocoel (Platyhelminthes: Proseriata and Rhabdocoela)

“…Additionally, kleptoplasty, which consists of sequestering algal plastids that provide their host with carbon and oxygen derived from photosynthesis, has been demonstrated in rhabdocoel microturbellarians ( Graff 1905 , Luther 1948 , Karling 1974 , Rivest et al 1999 , Adam and Balzer 2001 , Van Steenkiste et al 2019 ). The representativies of Proseriata and Rhabdocoela orders are amongst the most diverse and prevalent microturbellarians in marine sandy habitats ( Curini-Galletti 2001 , Fonseca et al 2010 , Schmidt-Rhaesa 2020 , Curini-Galletti et al 2023 ). Proseriates are exclusively carnivorous, with records of predation on crustaceans, annelids, hydroids, ostracods and scavenging activities, even involving beached fish ( Palombi 1926 , Bush 1966 , Bilio 1967 , Murina 1981 , Watzin 1983 , Watzin 1985 , Watzin 1986 , Curini-Galletti et al 2020 ).…”