Lygdamis Kinberg, 1867

Salazar-Vallejo, Sergio I. & León-González, J. Angel De, 2025, Additional new species of marine annelids from Clipperton Island (Nereididae: Pilargidae: Sabellariidae), European Journal of Taxonomy 1026, pp. 1-29 : 15-16

Genus Lygdamis Kinberg, 1867

Lygdamis Kinberg, 1867: 350 .

Tetreres Caullery, 1913: 200 (partim).

Lygdamis – Johansson 1927: 81 (diagn.). — Hartman 1944: 331 (syn.). — Kirtley 1994: 116 (diagn., syn., key). — Capa et al. 2012: 261 (diagn.).

Type species

Lygdamis indicus Kinberg, 1867 , by monotypy.

Diagnosis (modified from Capa et al. 2012)

Sabellariids with opercular lobes completely separated; outer and inner paleae arranged in semicircles. Nuchal hooks falcate, without limbation. Median organ cylindrical truncate or tapered blunt. Tentacles in parallel series (compound). Four parathoracic segments, each with lanceolate paleae and capillaries in each parapodial branch. Branchiae from segment 2 to mid-abdominal segments.

Remarks

Caullery (1913) noted there were two groups of species, separated by the number of parathoracic chaetigers, in what he regarded as Pallasia de Quatrefages, 1848 , and he also indicated that de Quatrefages had not clarified the number of parathoracic chaetigers. He restricted Pallasia to include species with three parathoracic chaetigers, whereas for those provided with four, he proposed Tetreres . Pallasia had been used before in dipterans ( Robineau-Desvoidy 1830), and in fishes ( Nardo 1840), rendering invalid its usage for polychaetes. Annenkova (1925) proposed Pallasina as a new name for Pallasia . Johansson (1926: 6; 1927: 81) concluded that Tetreres was a junior synonym of Lygdamis , and he might not have seen the paper by Annenkova, but it would make no difference for nomenclatural purposes. Tetreres Caullery, 1913 was listed above in the list of synonyms, but in part, because three species Caullery listed actually belong in Lygdamis , as indicated by Kirtley (1994: 3).

After de Quatrefages (1848), Johansson (1927) made the most extended study on sabellariids including histological details. Johansson included keys to genera, but the most complete revision was by Kirtley (1994), because he modified the generic composition of the family, proposed some genera, and described many species. In Lygdamis, Kirtley described 7 species and included a key to the then known 16 species. Lechapt & Kirtley (1998) slightly modified the previous key, but because of some problems running it, a new key is presented below to the known species.

On the other hand, a nomenclatural note must be included regarding Tetreres . Caullery (1913) listed five species in the genus and newly combined as T. laevispinis ( Grube, 1870) , T. giardi ( M’Intosh, 1885) , T. murata ( Allen, 1904) , T. asteriformis ( Augener, 1906) , and T. porrecta (Ehlers, 1908) . The first three belong in Lygdamis , as indicated by Kirtley (1994; see key below), whereas the latter two belong elsewhere.

Kirtley (1994: 188) retained Tetreres for species like the last two ones, and for seven species newly described by him. His proposal and separation were confirmed in recent studies ( Capa et al. 2012;

Hutchings et al. 2012). However, Kirtley (1994: 188) proposed Hermella varians Treadwell, 1902 as its type species, but this is incorrect.

Because Caullery did not indicate the type species for Tetreres , a subsequent designation is in order. However, the species to be designated must be one of those included in the original proposal (ICZN 1999, Arts 67.2, 69.1). Caullery (1913: 200) newly combined H. varians in Pallasia , not in Tetreres , and this listing might made Kirtley think his proposal was code compliant, but it is not. Consequently, the type species by subsequent designation must be Sabellaria ( Pallasia) asteriformis Augener, 1906 , which is a junior synonym of Hermella varians Treadwell, 1902 , as confirmed by Kirtley (1994: 197) after the study of their type specimens.