Notoplana felis, Rodríguez & Hutchings & Williamson, 2021

Rodríguez, Jorge, Hutchings, Pat A. & Williamson, Jane E., 2021, Biodiversity of intertidal marine flatworms (Polycladida, Platyhelminthes) in southeastern Australia, Zootaxa 5024 (1), pp. 1-63 : 44-46

Notoplana felis sp. nov.

( Fig. 17 )

Material examined: One specimen sagittally sectioned. Holotype: AM W.51326 (15 slides).

Notoplana longisaccata Hyman, 1959 . AM W.3692 (holotype).

Type locality: Australia, Victoria, Cats Bay, Phillip Island , 38°30’24.6”S, 145°07’33.8”E. Coll. Jorge Rodriguez, Patrick Burke and Louise Tosetto, July 12 th, 2018 .

Etymology: The specific name refers to the Latin term for “cat” as a reference to the place where it was discovered, Cat Bay.

Description: Body elongated with rounded ends. Length 1.2 cm. Dorsal surface pale cream ( Fig. 17A ). Tentacular eyes present in two clusters, cerebral eyes located in two elongated parallel clusters above brain area ( Fig. 17A, C ). Ruffled pharynx located anterior to the middle of the body, oral pore opening posterior to its centre ( Fig. 17B ).

Male and female gonopores located separate behind pharynx. Male copulatory apparatus consists of a seminal vesicle, an interpolated prostatic vesicle and an armed penis papilla with a short and slender stylet, directed backwards ( Fig. 17D–H ). Vasa deferentia run ventrally and joins distally seminal vesicle. Seminal vesicle ovalshaped and provided with a strong muscular layer ( Fig. 17G ). Ejaculatory duct joins distally prostatic vesicle and projects into its lumen ( Fig. 17G ). Oval prostatic vesicle provided with a strong muscular layer, lined with tubularly chambered glandular epithelium and provided with extra-vesicular glands ( Fig. 17G ). Penis papilla short, thick and conical-shaped, armed with a slender stylet and housed in a penis-pocket ( Fig. 17E, H ).

Female system located posterior to male apparatus ( Fig. 17D, H ). Thick vagina externa runs vertically, connects with vagina interna and loops anteriorly towards male system before turning back posteriorly and receiving oviducts ( Fig. 17H ). End of vagina interna connects with Lang’s vesicle, reaching the hind end of the animal ( Fig. 17H ).

Remarks: The new species belongs to the genus Notoplana due to the presence of a pharynx positioned anterior to the middle of the body, male copulatory system with an interpolated prostatic vesicle lined with tubularly chambered glandular epithelium and an armed penis papilla with a stylet, and a female system with Lang’s vesicle.

Notoplana felis sp. nov. most closely resembles another Australian Notoplana species , N. longisaccata Hyman, 1959 . Notoplana longisaccata possesses a wide pharynx situated in the middle of the body compared to the slender and anteriorly positioned pharynx of N. felis sp. nov. Both N. longisaccata and N. felis sp. nov. present short and armed penis papillae; however, the penis papilla of N. longisaccata is slender while that of N. felis is thick and conical-shaped. The main difference between both species is the presence of an exceedingly long Lang’s vesicle in N. longisaccata (about 1/6 of the length of the preserved worm), while that of N. felis is the same size as the rest of the female system.

Molecular remarks: Notoplana felis sp. nov. appeared in a clade including Notoplana australis , Amyris hummelincki and Leptoplana tremellaris with low support (68/0.76) and appearing as a polytomy in the BI analysis. The genus Notoplana appeared as paraphyletic with N. delicata and N. atomata more closely related to the Notocomplana clade and N. queruca clustering with Notocomplana ferruginea in a separate clade.

Distribution: Known only from type locality.

Figures

FIGURE 17. Notoplana felis sp. nov. A. Dorsal view of live specimen. B. Details of the pharynx and reproductive systems. C. Arrangement of the eyes. D. Sagittal reconstruction of the reproductive system. E–H. Histological sections of the reproductive system.