Kuma albiventer ( Marcus, 1954 )

Hooge, Matthew D. & Tyler, Seth, 2007, Acoela (Acoelomorpha) from Belize, Zootaxa 1479 (1), pp. 21-33 : 22-23

Kuma albiventer ( Marcus, 1954)

( Figs. 1B, C )

Haploposthia albiventer: Marcus 1954 (p 420); Mamkaev 1967 (p 40); Dörjes 1968 (p 97); Dörjes and Karling 1975 (p 180).

Kuma albiventer: Faubel 1976 (p 35); Hooge and Smith 2004 (p 16); Tekle 2004 (p 86); Hooge and Rocha 2006 (p 17).

Material. Living specimens in squeeze preparations; one set of 2-µm-thick serial sections of epoxy-embedded specimen stained with toluidine blue.

Localities. East of Carrie Bow Cay (16°48’09” N, 88°04’55” W), from fine-grained sand in a sand trough at 30 m depth, south of Carrie Bow Cay at 3–8 m depth from sand collected at a sand bore (16°45’53” N, 88°07’09” W), and from Twin Cays near West Bay (16°49’56” N, 88°06’29” W), from subtidal sand among mangrove roots and Thalassia sp .

Description. Mature specimens ~ 460 µm long when fully elongated and ~ 90 µm wide ( Fig. 1B ). Body cylindrical. Anterior and posterior ends rounded; posterior more blunt. Body color dark reddish-brown by transmitted light. Often with prominent unpaired oocytes in posterior portion of body.

Male gonopore terminal at posterior end of body ( Fig. 1C ). Ciliated male antrum leads to ring of granular gland cells. Conspicuous mucoid gland cells surround seminal vesicle ( Fig. 1C ).

Remarks. Prior to this collection, Kuma albiventer was known only from the Island of São Sebastiao, off the coast of the state of São Paulo, Brazil ( Marcus 1954, Hooge & Rocha 2006). Our Belize specimens appear almost identical to those from Brazil and their conspecificity is confirmed by the presence of the ring of gland cells with granular contents located at the proximal end of the male antrum, which are interspersed with the more prominent mucoid glands ( Fig. 1C ).

Figures

FIGURE 1. Photomicrographs of living acoel specimens. A. Haploposthia vandula. B. Kuma albiventer. C. Male copulatory organ of Kuma albiventer.