Ventromma halecioides (Alder, 1859)

Estrada-González, Mariae C., Agüero, José & Mendoza-Becerril, María A., 2023, Medusozoans from the Mexican Pacific: a review based on historical literature and recent observations, Journal of Natural History 57 (1), pp. 784-853 : 826

Ventromma halecioides (Alder, 1859)

( Figure 7A, B )

Material examined

3 colonies, polyp, with gonophores; Agua de Yepiz, La Paz Bay, Baja California Sur, 24.288° N, 110.630°W; depth 0–1 m; 24 June 2018; on the algae Hypnea sp. , Laurencia sp. , and Sargassum sp. ; ECO-CH-Z 11789. – Several colonies, polyp, without gonophores; Punta Los Muertos, Baja California Sur, 24.248°N, 110.150°W; depth 1–2 m; 20 July 2018; on the algae Centroceras gasparrinii , Laurencia pacifica , Padina mexicana , and Sargassum sp. ; ECO-CH-Z 11770.

Identification (after Calder 1997)

Colonies erect; hydrocaulus monosiphonic, alternately branched, divided into internodes by transverse nodes. Internodes slightly curved, each one supporting a distal hydrocladial apophysis and one axillary nematotheca. Hydrocladia unbranched, divided into athecate and thecate internodes by slightly oblique nodes; athecate internodes short, one at the base of hydrocladia and occasionally elsewhere; thecate internodes large, each one with a hydrotheca, and two nematothecae, one median inferior and the other superior. Hydrotheca cup-shaped, margin entire. Hydranth exposed and larger than hydrotheca.

Distribution

Previously recorded in the western Gulf of California, Baja California Sur ( Mendoza-Becerril et al. 2020). In the MP, it has been recorded from Baja California ( Fraser 1948) and Oaxaca (Humara and Cruz-Gómez 2018).

Figures

Figure 7. (A, B) Ventromma halecioides (Alder, 1859): A, hydrocaulus; B, hydrotheca. (C, D) Monotheca flexuosa (Bale, 1894): C, hydrocaulus; D, hydrotheca. (E, F) Plumularia floridana Nutting, 1900: E, hydrocaulus; F, hydrotheca. (G, H) Dynamena crisioides Lamouroux, 1824: G, colony; H, hydrotheca. (I, J) Dynamena disticha (Bosc, 1802): I, colony; J, hydrotheca. (K, L) Pasya quadridentata (Ellis and Solander, 1786): K, colony; L, gonotheca. Scale bars: A, H, I, K, L = 500 μm; B, D = 100 μm; C, E = 250 μm; F, J = 200 μm; G = 1 cm. Drawings made by Nicholas Bezio.