Laonicespecies (Polychaeta, Spionidae) from the Whittard Canyon (NE Atlantic) with descriptions of two new species

Abstract

Four species of Laonice (Annelida: Spionidae) were collected from the lower bathyal depths (3300–3700 m) in the Whittard Canyon, NE Atlantic. Two are herewith described as new species: Laonice whittardensis sp. nov. and Laonice natae sp. nov. The other two are Laonice blakei Sikorski & Jirkov, 1988 and Laonice magnacristata Maciolek, 2000. Laonice whittardensis has genital pouches appearing from chaetiger 3, prostomium free of peristomium and bidentate hooks. Laonice natae belongs to the subgenus Appelloefia nov. with prostomium distinct from the peristomium, more than two vertical rows of capillaries in several anterior chaetigers, genital pouches present on a limited number of segments or totally absent. However, the absence of pronounced anterior widening of the body together with anterior branchiae, which are remarkably (nearly twice) longer than the notopodial postchaetal lobes, the narrow lanceolate notopodial postchaetal lobes, the pronounced pointedness of all postchaetal lobes (both notopodial and neuropodial) in the anterior half of body at least, and absence of genital pouches and the size of the body all distinguish L. natae from other species belonging to this subgenus. An identification key to all nine known deep-water (>400 m depth) Laonice species in North Atlantic is given and four previously recognized sub-generic groups are formally named: Laonice, Sarsiana subgen. nov., Appelloefia subgen. nov., Norgensia subgen. nov.

Diversity and distribution of Laonice species (Annelida: Spionidae) in the tropical North Atlantic and Puerto Rico Trench

“…Until now, around 16 deep-sea Laonice species have been described, mainly based on morphology 9 . Unfortunately, it is not possible to perform subsequent molecular studies with most of the described material, due to fixation, unless new material is collected from the respective type localities.…”

Abyssal fauna of polymetallic nodule exploration areas, eastern Clarion-Clipperton Zone, central Pacific Ocean: Annelida: Spionidae and Poecilochaetidae

“…Remarks: Genus Laonice consists of 38 described species with many more not formalized especially from deep sea environments, in part reflecting the problematic taxonomy of this group (e.g., Sikorski et al 2017;Bogantes et al 2018). Laonice has recently been divided into four subgenera: Laonice, Sarsiana, Appelloefia, and Norgensia by Sikorski et al (2017), based on characters such as fusion of prostomium and peristomium, development of nuchal organs, presence of notopodial hooks, number of rows of capillaries in anterior chaetigers, and the distribution of branchiae and genital pouches.…”

“…Remarks: Genus Laonice consists of 38 described species with many more not formalized especially from deep sea environments, in part reflecting the problematic taxonomy of this group (e.g., Sikorski et al 2017;Bogantes et al 2018). Laonice has recently been divided into four subgenera: Laonice, Sarsiana, Appelloefia, and Norgensia by Sikorski et al (2017), based on characters such as fusion of prostomium and peristomium, development of nuchal organs, presence of notopodial hooks, number of rows of capillaries in anterior chaetigers, and the distribution of branchiae and genital pouches. This division has not been based on a phylogenetic approach and is not followed here also due to the fact that Although Laonice is commonly encountered in deep-sea samples (Guggolz et al 2019), currently only 11 species of Laonice have been described from waters deeper than 400 m (Sikorski et al 2017;Sikorski et al 2021).…”

“…Laonice has recently been divided into four subgenera: Laonice, Sarsiana, Appelloefia, and Norgensia by Sikorski et al (2017), based on characters such as fusion of prostomium and peristomium, development of nuchal organs, presence of notopodial hooks, number of rows of capillaries in anterior chaetigers, and the distribution of branchiae and genital pouches. This division has not been based on a phylogenetic approach and is not followed here also due to the fact that Although Laonice is commonly encountered in deep-sea samples (Guggolz et al 2019), currently only 11 species of Laonice have been described from waters deeper than 400 m (Sikorski et al 2017;Sikorski et al 2021). In ABYSSLINE material, seven species of Laonice have been recognized based on morphology and molecular data.…”

New sublittoral species of Laonice (Annelida: Spionidae) from southern Asian coasts

“…Laonice persica sp. nov. has the prostomium completely fused with the peristomium, which places the species in L. (Laonice) as defined by Sikorski et al (2017). It also lacks entire dorsal transverse crests connecting the notopodial postchaetal lamellae, and so belongs to the L. cirrata complex, together with L. brevicornis (kinberg, 1866) [including the junior synonyms L. aperata radashevsky & Lana, 2009 and L. petersenae radashevsky & Lana, 2009], L. quadridentata Blake & kudenov, 1978, L. bassensis Blake & kudenov, 1978, L. shamrockensis Sikorski, 2003, L. asaccata Sigvaldadóttir & Desbruyères, 2003, L. pinnulata radashevsky & Lana, 2009, L. cricketae Sikorski & Pavlova, 2016, and L. plumisetosa Bogantes et al, 2018 cirrata is much larger (adults up to 5 mm wide), with hooks usually appearing bidentate in lateral view (tridentate in L. persica sp.…”