Plehnia cascaisensis sp. nov. (holotype, MNHNC MB16-000107). Histological sections are postero-anteriorly oriented: A. Histological section of the long internal vagina (holotype); B. Histological section of the end of the internal vagina and Lang’s vesicle (holotype); C. Sagittal reconstruction of the reproductive system (holotype). Abbreviations: cg, cemental glands; ed, ejaculatory duct; el, epithelial lining; ev, external vagina; fp, female pore; i, intestine; iv, internal vagina; lv, Lang’s vesicle; ma, male atrium; mp, male pore; mw, muscular wall; ov, oviduct; ph, pharynx; pp, penis papilla; pv, prostatic vesicle; sb, spermiducal bulbs; spv, spermiducal vesicle.