Geitodoris patagonica Odhner, 1926

Cetra, Nicolás & Roche, Andrea, 2023, Nudibranchia (Mollusca: Gastropoda) from San Matías Gulf, Northern Argentine Patagonia, Zootaxa 5244 (5), pp. 455-473 : 461-462

Geitodoris patagonica Odhner, 1926

( Figures 2G, 2H , 3E, 3F )

Material examined. Argentina, Río Negro , Caleta Los Hornitos, four specimens, intertidal, December 2017 (one specimen deposited, MLP-Ma 14656) .

Description. Length up to 40 mm, body white, yellow to orange or dark gray, with dark spots on the dorsum. Dorsal mantle is densely covered with tubercles of two different sizes. Rhinophores lamellate, 12 to 16 lamellae. 6-8 bi or tripinnate gill leaves around the anal papilla ( Figure 2G ). Radular formula is 16 x 12.24.0.24.12 (MLP-Ma 14656). The lateral teeth with small curved and pointed cusp. Marginal teeth delicate, very close standing lamellae ( Figure 3E, 3F ).

Geographic distribution and depth range. Argentina, San Matías gulf ( Scarabino 1977), Northern Chubut, Patagonia to Malvinas (Falkland) Islands (Schrödl 2000, Muniain 2001). Found in hard and intertidal bottoms under rocks up to 25 m depth .

Biology. The egg masses of this species are gelatinous yellowish color tape of about 20 mm in length, with up to three full spiral turns. The egg mass is deposited on rocks ( Figure 2H ).

Remarks. Only one species of Geitodoris is recorded for the Magellanic Province: Geitodoris patagonica . Another species, Geitodoris pusae ( Marcus 1955) , known from warm waters from Florida along Brazil to the Argentine coast, is an amphiatlantic species recorded by Marcus and Marcus (1969) on the north coast of Argentina, off Bahía Blanca at 68 m depth. According to Muniain (2001), G. pusae differs from G. patagonica by the presence of a reticulum and spicules present in the external duct of the vestibular gland. Muniain (2001) discussed the doubtful record of G. patagonica made by Carcelles (1944) from the littoral zone of Puerto Quequén (38º34'S) as it did not fit the original description given by Odhner (1926), suggesting that it should be disregarded.

Figures

FIGURE 2. (A) Doris fontainii, (B) Rostanga pulchra, (C) Diaulula punctuolata, (D) egg mass of Diaulula punctuolata, (E) Gargamella immaculata, (F) egg mass of Gargamella immaculata, (G) Geitodoris patagonica, (H) egg mass of Geitodoris patagonica.

FIGURE 3. Scanning electron micrographs. (A) Doris fontainii (MLP-MA 14653): radular teeth; (B-C) Rostanga pulchra (MLP-Ma 14654): (B) radular teeth (C) detail of the lateral teeth; (D) Diaulula punctuolata (MLP-Ma 14655): radular teeth; (E-F) Geitodoris patagonica (MLP-Ma 14656): (E) lateral and marginal teeth (F) detail of the marginal teeth.