ABSTRACT
Haliclona (Flagellia) Van Soest, 2017 is a recently erected subgenus characterized by the presence of flagellosigma microscleres which are often distinctive between species (Van Soest 2017). Members of the taxon also have normal sigmas within a confused skeleton formed by oxea megascleres. The subgenus has a global distribution and contains 10 species (Van Soest et al. 2019). A large and abundant new species collected throughout the southern Gulf of St. Lawrence is characterized by thick and abnormally shaped flagellosigmas, two sizes of oxea, and abundant normal sigmas. Lambe (1896) previously reported Haliclona (Flagellia) porosa (Fristedt, 1887) from the Gulf of St. Lawrence, and the species is known to occur in nearby Arctic waters (Fristedt 1887; Lundbeck 1902; Hentschel 1916; Koltun 1959, 1966; Van Soest 2017; Dinn Leys 2018). However, H. (F.) porosa is characterized by the presence of very few normal sigmas and no thick flagellosigmas. Type specimens were preserved in 95% ethanol and were deposited in the Atlantic Reference Centre (ARC) in St. Andrews, New Brunswick, Canada. The taxonomic identification was performed through spicule analysis using light and scanning electron microscopy, following methods described by Dinn et al. (2020).
Subject(s)
Haliclona , Animals , CanadaABSTRACT
Three new species records, Axinella arctica (Vosmaer, 1885), Semisuberites cribrosa (Miklucho-Maclay, 1870), and Cladocroce spatula (Lundbeck, 1902), and one new combination, Plicatellopsis bowerbanki (Vosmaer, 1885) comb. nov. from eastern Canada are described. The four species have similar growth forms which are either fan or cup-shaped with obvious stalks. This is the first description of a member of the genus Plicatellopsis in the North Atlantic, and the second record of the genus in the northern hemisphere. The four species described here have a history of misidentification in eastern Canada and this work aims to guide future identifications in the region.
Subject(s)
Axinella , Porifera , Animals , Atlantic Ocean , CanadaABSTRACT
The deep-water sponge fauna of the Canadian Arctic remains to be fully described, particularly in areas that are not sampled by fisheries stock-assessment trawl surveys such as the major bays and fjords of the northern Labrador Sea and Baffin Bay. Frobisher Bay is a large inlet located on the southeast of Baffin Island. We used a remotely operated vehicle, as well as box cores and Agassiz trawls to study the sponge fauna of this bay. Over three years, from 2015 to 2017, sponge specimens were collected representing 24 distinct sponge taxa. Dense gardens of Iophon koltuni Morozov, Sabirov, Zimina, 2019 were discovered at a site near Hill Island in inner Frobisher Bay. The species has a unique finger-like growth form and provides complex habitat in the inner bay. Other sponge species are new to the Northern Labrador marine ecoregion. In particular, we report geographic range extensions of Tetilla sibirica (Fristedt, 1887) and Craniella polyura (Schmidt, 1870), and provide spicule measurements and descriptions of Iophon piceum (Vosmaer, 1882) and Mycale lingua (Bowerbank, 1866). These species identifications, geographic range extensions, and an expanded description of a species synonym represent the first inventory of the sponge fauna of Frobisher Bay.
