Bryocamptus (Bryocamptus) minutus (Claus, 1863)

Novikov, Aleksandr, Sharafutdinova, Dayana & Chertoprud, Elena, 2023, Two new species of Bryocamptus (Copepoda, Harpacticoida, Canthocamptidae) from the Russian Arctic and comparison with Bryocamptus minutus (Claus, 1863), ZooKeys 1138, pp. 89-141 : 89

Bryocamptus (Bryocamptus) minutus (Claus, 1863)

Subspecies.

B. (B.) minutus minutus (Claus, 1863), B. (B.) minutus schizodon ( Mrázek, 1893).

Nomen dubium.

B. (B.) minnesotensis (Herrick, 1884).

Remarks.

Bryocamptus (B.) minutus is a taxonomically rather complex species due to a rather long history of study and wide distribution. According to Article 45.6 of the International Code of Zoological Nomenclature, a number of forms of this species must be treated as separate subspecies (ICZN 1999). However, in the case of B. (B.) minutus vejdovskyiformis Thallwitz, 1916, this is probably a form that does not have subspecies status and is either an aberrant specimen(s) or simply variability ( Thallwitz 1916). Simple dentiform and bifid spinules are also found in other related species, both within the same population and in one individual. This has been described in B. hutchinsoni Kiefer, 1929 ( Wilson 1956), B. vejdovskyi ( Mrázek, 1893) ( Reed 1990) and also in B. putoranus sp. nov. (in this article).

A number of authors noted variability in the number of outer spines on the third exopodal segment of P4, which was the reason for Lang’s description of the forms: B. minutus f. typica Lang, 1957 and B. minutus f. bispinosa Lang, 1957 ( Lang 1957). We suggest that these forms do not have a taxonomic rank, since such variability is common for this group of species.

Another form of B. minutus f. simplicidentata (Willey, 1934) has been synonymized with B. hutchinsoni based on structure of caudal rami ( Wilson 1956) but although figuring mistakenly and without literature support as valid in WORMS database ( Walter and Boxshall 2021).

A rather interesting finding is described from the Iberian Peninsula as B. minutus ( Caramujo and Boavida 2009). Based on the depicted limbs, it can be assumed that this is either B. minutus schizodon or a separate species. It differs from B. minutus minutus in the two-segmented endopod P2, short bifid spinules on the anal operculum, and slight displacement of the caudal setae to the ventral side of caudal rami. In general, these characters are already enough to distinguish a separate species.