Marionina colpites

Main Authors: Klinth, Mårten J., Rota, Emilia, Martinsson, Svante, Prantoni, Alessandro L., Erséus, Christer
Format: info publication-taxonomictreatment Journal
Terbitan: , 2021
Subjects:
Online Access: https://zenodo.org/record/6461131
Daftar Isi:
  • MARIONINA COLPITES (STEPHENSON, 1932) (FIG. 4D–F) Enchytraeus colpites Stephenson, 1932: 260–263, figs 12–13. Lumbricillus colpites – Nielsen & Christensen, 1959: 96. Type material: BMNH 1933.2.23.885–892, eight mature sectioned specimens (studied). Syntypes. Loc. Shore of Bay of Isles, South Georgia Leg. ‘ Discovery’ 1925–1927 (Stephenson, 1932). Type locality: Shore of Bay of Isles, South Georgia Island. Additions to Stephenson’s original description: Chaetae ~110 μm long. Epidermis covered with rows of pale gland cells, and with a few rows of deeply staining granular gland cells, latter rows aggregated anterior and posterior to chaetae (see M. fusca below). Dorsal vessel with peristomial bifurcation. Nephridia in 7/8– 10/11 and postclitellar segments. Ventral nerve cord with large subbuccal bulb; see Marionina discussion above. Sperm funnels ≥ 900 μm long, 230 μm wide. Spermathecae (Fig. 4E, F) ≥ 600 μm long, 60 μm wide at duct, 180 μm wide at ampulla, with glands 55–100 μm wide surrounding pore. Remarks: Stephenson was uncertain whether to place this species in Lumbricillus or Enchytraeus Henle, 1837 (and apparently did not consider Marionina), and decided pro Enchytraeus because of the lack of lobed testis sacs and absence of defined penial bulb. The testes are indeed small but do appear partly lobed; we could not make out whether the mass of developing cells was fully enveloped in testis sacs or distally free, but the mass is enveloped in a seminal vesicle as it bulges into anterior segments. The male apparatus, with its separate glands that discharge independently around the male pore, is similar to that described for M. benhami.
  • Published as part of Klinth, Mårten J., Rota, Emilia, Martinsson, Svante, Prantoni, Alessandro L. & Erséus, Christer, 2022, New insights into the systematics of Lumbricillus and Marionina (Clitellata: Enchytraeidae) inferred from Southern Hemisphere samples, including three new species, pp. 1103-1133 in Zoological Journal of the Linnean Society 194 (4) on page 1124, DOI: 10.1093/zoolinnean/zlab073, http://zenodo.org/record/6461085