Typhlopolycystis maikoni, Schockaert & Moons & Janssen & Tessens & Reygel & Revis & Jouk & Willems & Artois, 2019

Schockaert, Ernest R., Moons, Patricia, Janssen, Toon, Tessens, Bart S., Reygel, Patrick C., Revis, Nathalie, Jouk, Philippe E. H., Willems, Wim R. & Artois, Tom J., 2019, On the genus Typhlopolycystis Karling, 1956 (Platyhelminthes, Kalyptorhynchia, Polycystididae), with data on the five known species and the description of eleven new species, Zootaxa 4603 (1), pp. 81-104 : 94

Typhlopolycystis maikoni n. sp Schockaert & Artois.

( Figs 10 E–F)

Diagnosis. Colourless species of Typhlopolycystis , about 1 mm long with a proboscis of 1/6–1/5 of the body length and with eyes. The prostate stylet is curved, 72 µm long with a thickened proximal “head” of about 22 µm at its concave side. The accessory stylet is attached to the prostate stylet at the opposite side. It makes a turn of 180° and then follows the curve of the prostate stylet; it ends in a point and is 77 µm long, measured from the point of attachment to the prostate stylet.

Occurrence. Brasil: near the Island of Itaçucê , São Sebastião (São Paulo), shell gravel at 7 m depth. (by Schockaert, 30 October 2012) (Type Locality) .

Material examined. Observations on a live animal and micrographs of the live animal. One whole mount (Holotype, SMNH nr 8959)

Etymology. Species name in honour of Dr. Maikon Di Domenico, who was one of the collectors of the samples near Itaçucê and who was highly involved in the logistics of the workshop on the Taxonomy and Diversity of Marine Meiofauna, Brazil.

Additional data. The copulatory organ of T. maikoni n. sp. is very similar to that of T. pluvialiae n. sp.. The prostate stylet is slightly longer (72 µm) than that of T. pluvialiae n.sp (63 µm) and slightly less curved. It is also narrower. The accessory stylets are less different in length, resp. 77 µm and 74 µm. The thickened proximal curl (“head”, x in Fig. 1F ) is shorter than in T. pluvialiae n.sp (22 µm and 29 µm). More obvious differences are the size of the proboscis: large (1/4 of body length) in T. pluvialiae n. sp., and less than 1/5 of body length in T. maikoni n. sp. and the fact that the Brazilian species has eyes, while the Lanzarote species does not.

Figures

FIGURE 1. Generalised anatomy of a species of Typhlopolycystis. (A) General construction. (B) Female atrial organs. (C) Male atrial organs. (D-G) The different types of copulatory organ in species of Typhlopolycystis. (scale = 20 µm)

FIGURE 10. Typhlopolycystis pluvialiae n. sp. (A) The living animal. (B, C) Micrograph and drawing of the caudal half of the living animal. (D) The copulatory organ in the holotype. Typhlopolycystis maikoni n.sp. (E) The living animal. (F) The copulatory organ. (scale = 20 µm except in E)