Martensocelis martensi, Schockaert & Curini-Galletti, 2025

Martensocelis martensi sp. nov.

ZooBank: urn:lsid:zoobank.org:act:

( Fig. 3 View FIGURE 3 )

Diagnosis. Large species of Martensocelis more than 10 mm long, with multiple pharynges. Ovaries are midway between the anteriormost pharynx and the brain. With 4–5 testes in a row in front of the pharynges. With a recurve stylet 150–175 µm long, surrounded by a girdle of 30–40 needles, ranging 50–80 µm in length; they have a strong terminal hook, relatively long and slender in the shorter needles and short and thick in the longer ones. With two vaginas, and a globular genito-intestinal duct at a distance from the female pore. Karyology: n=10.

Occurrence. Fishermans Bay , Anna Bay, New South Wales, Australia; intertidal among rocks, in clean coarse shelly sand (Lat. –32.788978; Long. 152.092200) ( August 1996) ( type locality) .

Material studied. Live animals, nine whole mounts, one of which designated as holotype ( QM G238526 ) , the other eight as paratypes ( CZM 859–866 ); four specimens sagittally sectioned ( CZM 867–870 ) .

Etymology. Genus and species names are dedicated to Dr. Paul Martens, a good friend of both authors and who described the first species with a similar copulatory organ.

Description. Large animals, up to 11 mm long, with the epidermis entirely ciliated and with intra-epithelial nuclei. Adhesive glands on dorsal and ventral sides, often grouped into patches at the caudal end of body. With up to 30 pharynges, regularly arranged into a longitudinal row, and departing from the gut at a distance of about 30 µm from each other ( Fig. 3 A View FIGURE 3 ). These pharynges are very muscular, with both longitudinal and circular muscle layers strongly developed. Their oesophagus is long, and occupies about ¾ the length of the entire pharynx. The prostate vesicle is S-shaped; only intracapsular prostate glands are present. The two seminal vesicles enter the prostate vesicle close to each other into its sub-proximal and ventral part ( Fig. 3 F View FIGURE 3 ). The stylet is around 170 µm in length, slender and recurve, with an oblique, acute distal opening and a funnel-shaped proximal part, 20– 22 µm wide. The stylet is surrounded distally by a girdle of 30–40 needles, ranging 50–80 µm in length; they have a strong terminal hook, relatively long and slender in the shorter spines and short and thick in the longer ones ( Fig. 3 D, E View FIGURE 3 ). Posterior to the mouth, the two oviducts join and form a large prepenial bursa lined with a high vacuolated epithelium of the resorbiens type, which is connected to two muscular vaginas ( Fig. 3 F View FIGURE 3 ). The female duct continues posteriorly, lined by a thick epithelium without vacuoles, and ciliated in its distalmost part. About midway between copulatory organ and female pore there is a short genito-intestinal duct, that opens into a large, sperm-containing vesicle lined by a high epithelium ( Fig. 3 C, F View FIGURE 3 ). This vesicle then opens into the gut, and may act as a secondary resorbiens bursa. The female pore is surrounded by large cement glands.

Karyotype n=10; FN: 11.