Related Experiment Video
Updated: Apr 28, 2026

Microsurgical Obstruction of Testes Fusion in Spodoptera litura
Published on: July 16, 2021
A new Stygarctus (Arthrotardigrada: Stygarctidae) from Japan, with entangled seminal receptacle ducts
1Department of Zoology, Division of Biological Science, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.;
Abstract:
Stygarctus ayatori sp. nov. (Arthrotardigrada: Stygarctidae), is described from a sandy beach located at Okinoshima, Tateyama Bay, Boso Peninsula, Honshu, Japan. The most prominent characters were observed in the female genital structure, with the seminal receptacle ducts forming a three-dimensional entanglement near the exterior opening, and internal thickening situated peripheral to the gonopore and between the gonopore and anus. The new species is distinguished from the congeners by these characters; excluding S. abornatus McKirdy et al., 1976 for which there is no information on the genital structure. However, S. ayatori sp. nov. and S. abornatus can be differentiated by the presence of dorsal spines on the former species, which are absent from the latter.
More Related Videos
Related Concept Videos
Accessory Ducts of the Male Reproductive System
The epididymis is a small, comma-shaped organ located at the back of each testicle....
Accessory Glands of the Male Reproductive System
The epididymis is a small, comma-shaped organ located at the back of each testicle. The epididymis can be divided into three main parts: the head, body, and tail. The head of the epididymis...
Osmoregulation in Insects
Testes: Gross Anatomy
Each testis is surrounded by the tunica albuginea, a dense connective tissue layer that provides structural support and protection. This layer is covered by an outer serous membrane called the tunica vaginalis, which helps reduce friction...

