A new species of Flabelligeridae (Annelida), Trophoniella radesiensis n. sp., from Tunisia

Abstract

The family Flabelligeridae was previously represented in Tunisia by four genera including four species: Bradabyssa villosa (Rathke, 1843), Therochaeta flabellata (M. Sars in G.O. Sars, 1872), Pherusa plumosa (Müller, 1776), and Piromis eruca (Claparède, 1869). In this paper we report a fifth genus, Trophoniella, for the first time in Tunisia. The specimens were collected in Radés Station, Gulf of Tunis (Central Mediterranean) and belong to a new species, namely Trophoniella radesiensis n. sp., which is characterized by having: (1) a very smooth tunic, body covered dorsally, ventrally, and laterally by sediment grains (except in the posterior region), and (2) well-developed parapodia showing short neurohooks from chaetiger 6 to 19 and anchylosed neurohooks from chaetiger 20. Based on the 16S, the new species belongs to a low supported Piromis/Trophoniella clade and shows a 16.1% of genetic distance from Trophoniella hephaistos Jimi & Fujiwara, 2016, the single known species of the genus sequenced to date. [Zoobank lsid: urn:lsid:zoobank.org:act:D7C85C70-87FF-4AF4-8599-A8462B3FB8B1]

Trophoniella cucullata, a new flabelligerid species from Mediterranean Posidonia oceanica meadows (Annelida, Flabelligeridae)

“…The chaetigers with the sediment granules are characterized by a different colour pattern compared with the rest of the body: while the chaetigers of the ‘hood’ are reddish, the following ones are pale-yellow and are characterized by a relative scarcity of sediment particles. Such a distribution of the sediment granules on the body has not been observed in any other species belonging to this genus and the other five Mediterranean species show a different pattern of granule distribution: T. incerta and T. fernandensis lack sediments grains on their tunics while T. enigmatica , T. fauveli and T. radesiensis have tunics with sediment grains on both dorsal and ventral surfaces (Salazar-Vallejo, 2012; Chaibi et al ., 2019). A further important diagnostic character of the Trophoniella genus is the mid-body and posterior neurochaetae: anchylosed neurohooks in T. cucullata sp.…”

“…Although this family is characterized by unique features, its biology and its physiology have been little investigated; for instance, the anterior extremity of these species is retractable (prostomium, peristomium and the first one/two segments) and rarely exposed (Salazar-Vallejo, 2012, 2021), preventing a thorough understanding of important morphological traits. Further studies are warranted to clearly define the systematics of this taxon (Salazar-Vallejo, 2011, 2012, 2021; Chaibi et al ., 2019; Worms, 2022).…”

“…Within the family Flabelligeridae, the genus Trophoniella Hartman, 1959, revised by Salazar-Vallejo (2012), is closely related to genera Piromis Kinberg, 1867 and Pycnoderma Grube, 1877: species belonging to these genera are all characterized by a thick tunic, often covered with sediment grains, their notochaetae are multiarticulated at least in anterior or median chaetigers and possess a projected tongue-shaped branchial membrane with abundant sessile branchial filaments (Salazar-Vallejo, 2012; Chaibi et al ., 2019). The three genera can be discriminated based on the neurochaetae morphology, particularly those associated with posterior chaetigers.…”

Polychaete diversity in Tunisian waters as of 2021: an update with special emphasis on Non-Indigenous species

“…Zaâbi et al (2012) inventoried 86 new polychaete species from the North-east Tunisian coast, increasing the total number to 375 species. A new species was described from this same sector of the Tunisian coast and a new species was reported for the Mediterranean Sea (Chaibi et al, 2019 and2021, respectively). Other taxonomic and especially ecological studies have been conducted over the last decade in the Gulf of Gabès (Pérez-Domingo et al, 2008;Aloui-Bejaoui & Afli, 2012;Khedhri et al, 2014Khedhri et al, , 2016aKhedhri et al, , b, 2017aMosbahi et al, 2015aMosbahi et al, , b, 2016Mosbahi et al, , 2017Boudaya et al, 2019); these studies have led to the recording of several new polychaete species compared to the inventory of Ayari et al (2009).…”

“…The species in question belong to the collection of Ayari and Zaâbi (RF in Table 1). 3-Research on polychaetes and studies dealing with macrobenthic fauna, which were published after the last complete inventory of Tunisian polychaetes due to Ayari et al (2009), are revised and collated here, especially the data of Diawara et al (2008), Pérez-Domingo et al (2008, Ayari et al (2009), Zaâbi et al (2009Zaâbi et al ( , 2010Zaâbi et al ( , 2012, Khedhri et al (2014Khedhri et al ( , 2016Khedhri et al ( a, b, 2017, Mosbahi et al (2015Mosbahi et al ( a, b, 2017, Ounifi-Ben Amor et al (2015), Boudaya et al (2019), and Chaibi et al (2019. Other papers were consulted to check the distribution of species in other regions of the Mediterranean (e.g., Castelli et al, 2008;Çinar et al, 2014a, b;Mikac, 2015;Faulwetter et al, 2017;Bakalem et al, 2020).…”