Quasimicrura, Chernyshev, 2025

Genus Quasimicrura gen. nov.

urn:lsid:zoobank.org:act:4C7910A4-D241-44A3-BE6C-1FB025D70393

Type species. Cerebratulus dellechiajei Hubrecht, 1879 View in CoL .

Diagnosis. Lineidae with lateral horizontal cephalic slits and caudal cirrus. Cutis glands not penetrate outer longitudinal musculature of body wall; thick connective tissue layer under cutis absent. Proboscis modified heterotype, without outer longitudinal musculature (see Chernyshev, 2015), with two muscle crosses and two pairs of nerves present. Rhynchodaeum divides blood lacuna into two cephalic blood vessels. Vascular blood plexus present in foregut region. Foregut with subepithelial gland-cell zone. Cerebral ganglia without outer neurilemma; neurochords and neurochord cells not found. Two (?) frontal organs.

Generic composition. Quasimicrura dellechiajei (Hubrecht, 1879) comb. n.

Remarks. Micrura dellechiajei was re-described by Herrera-Bachiller et al. (2015). The phylogenetic analysis in that study showed the proximity of this species to the genus Notospermus , with, however, clade Micrura dellechiajei + Notospermus having low support. The phylogenetic analysis by Kajihara et al. (2022) provided a similar pattern. The phylogenetic analysis by Chernyshev and Polyakova (2023) showed a high support of the clade Micrura dellechiajei + Notospermus . Micrura dellechiajei differs from species of the genus Notospermus by the lack of the thick connective-tissue layer between the cutis and the outer longitudinal musculature of the body wall and by the presence of the frontal organs and caudal cirrus. According to Herrera-Bachiller et al. (2015), the proboscis of M. dellechiajei lacks outer longitudinal musculature, whereas in the Notospermus species, this musculature is present.

Etymology. The new generic name is feminine in gender, formed by adding the Latin prefix quasi - (meaning “seemingly”, “resembling”) to the name Micrura .