Pogaina sinensis Wang & Zhong 2019, n. sp.
Creators: name: Zhong, Lin-Hong
name: Xie, Yao-Hang
name: Hu, Xiao-Zhou
name: Chen, Yu-Si
name: Feng, Wei-Tao
name: Zhang, Yu
name: Wang, An-Tai
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Platyhelminthes
Rhabditophora
Rhabdocoela
Provorticidae
Pogaina
Pogaina sinensis

description: Pogaina sinensis Wang & Zhong n. sp.
(Figs. 1–2)
Locality. Specimens were collected in brackish water (water temperature: 18–20°C, salinity: 17–21‰) near Shekou Port, Shenzhen Bay, Shenzhen City, Guangdong Province, China (113°54′49″E, 22°28′58″N) by L.H. Z during February and March of 2018.
Material examined. Holotype: PLA-Pr001, one whole-mounted specimen. Paratypes: PLA-Pr002–003, two whole-mounted specimens; PLA-Pr004-007, serially-sectioned (sagittal) specimens; PLA-Pr008, whole-mounted stylet.
Etymology. Species name refers to the country where it was discovered.
Description. The animal is 400–600 μm long (ẍ=500 μm; n=3) and 140–160 μm wide (ẍ=150 μm; n=3). The cylindrical-shaped individual is fast-moving, with a rounded anterior end and tapered posterior end (Fig. 1A). The body is brownish-yellow, with symbiotic zooxanthellae distributed all over the body (Fig. 1B). The barrel-shaped pharynx is 70–80 μm long (ẍ=75 μm; n=3) and 45–60 μm wide (ẍ=52 μm; n=3) (Fig. 1B, 2A).
A pair of ellipsoidal-shaped testes, measuring 150–200 μm in length (ẍ=175 μm; n=3) and 50–60 μm in width (ẍ=55 μm; n=3), are situated at the ventral side posterior to the pharynx (Fig. 1B, 2A). The spherical shaped seminal vesicle (60–70 μm in diameter, ẍ=65 μm; n=3) is located at midpoint of the body. It connects with a curved prostate vesicle, which together form an arc-like structure. The prostate vesicle is surrounded by the well-developed circular muscle and the posterior end connects to the stylet (Fig. 1B, 2 A–B). The eosinophilic glands enter the prostate vesicle at the joint between prostate vesicle and seminal vesicle. The tubular-shaped stylet (70–80 μm long, ẍ=75 μm; 8–10 μm wide proximally, ẍ=9 μm; 3–5 μm wide distally, ẍ=4 μm; n=3) is located at male atrium and is slightly curved at the distal end (Fig. 1 B–F, 2A–C). A fusiform structure is present at 66% of the stylet, with a flange running through. The flange encircles the stylet, with its two ends attached to the midpoint and the distal end of the stylet. The gonopore is located at 66% of the body (Fig. 2 A–B).
Two vitellaria are situated dorsally at both sides of the body, extending from the pharynx to the posterior end (Fig. 1B, 2 A–B). A pair of ellipsoidal-shaped ovaries is located ventrally at 66% of the body, with the length of 70– 90 μm (ẍ=80 μm; n=3) and the width of 40–50 μm (ẍ=45 μm; n=3) (Fig. 1B, 2 A–B). The oviduct and vitelloduct run into a common duct (Fig. 2B), in which the shell glands (Fig. 2B) are present. The common duct is connected to the gonopore via a female canal (Fig. 2 A–B), where an enlarged structure filled with sperm is visible. The sphericalshaped seminal receptacle (70–80 μm in diameter, ẍ=75 μm; n=3) is filled with sperm (Fig. 1 A–B, 2A–B).
description: Published as part of Zhong, Lin-Hong, Xie, Yao-Hang, Hu, Xiao-Zhou, Chen, Yu-Si, Feng, Wei-Tao, Zhang, Yu & Wang, An-Tai, 2019, Two new brackish-water species of Pogaina (Rhabdocoela: Provorticidae) from China, pp. 353-364 in Zootaxa 4679 (2) on pages 355-356, DOI: 10.11646/zootaxa.4679.2.8, http://zenodo.org/record/3772623