Macrorhynchia philippina Kirchenpauer, 1872

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 : 824-825

Macrorhynchia philippina Kirchenpauer, 1872

( Figure 6G–I )

Material examined

1 colony, polyp, without gonophores; Caleritas Beach, La Paz Bay , Baja California Sur, 24.350N, 110.290°W; depth 0–1 m, 30 April 2017; on rock; ECO-CH-Z 11773 . – 1 colony, polyp, without phylactocarps; Punta Los Muertos, Baja California Sur, 24.248°N, 110.150°W; depth 1–2 m; 20 July 2018; on the alga Bryopsis sp ., ascidian, and Bryozoa ; ECO-CH-Z 11765 . – 1 colony, polyp, without phylactocarps; El Mogote Sand Bar, La Paz Bay , Baja California Sur, 24.159°N, 110.341°; depth 0–2 m; 1 July 2019; on ascidian; ECO-CH-Z 11796 .

Identification (after Calder 1997; Di Camillo et al. 2009)

Colonies erect; hydrocaulus polysiphonic basally and monosiphonic distally, twice-pinnately branched, divided into internodes by transverse to slightly oblique nodes. Internodes from the anterior side of the primary hydrocaulus with a distal hydrocladial apophysis, a mamelon, and two nematothecae, one basal and the other axillary. Hydrocladia divided into thecate internodes by oblique nodes, each internode with a hydrotheca, three nematothecae, one median inferior and one pair lateral, and two internodal septa. Hydrothecae with abcauline wall convex except for pronounced concavity just below margin; adcauline intrathecal septum prominent extending about halfway across the intrathecal cavity. Hydrothecal margin sinuous in lateral view, with two short lateral cusps and a short median abcauline cusp. Median inferior nematotheca reaches beyond the hydrotheca margin distally, adnate to the abcauline wall of hydrothecal as far as intrathecal septum; lateral nematothecae adnate to hydrothecal wall, extending beyond margin of hydrothecae.

Distribution

Previously recorded on the west coast of the Gulf of California, Baja California Sur ( Fraser 1938b, 1948; Baynes 1999), and for the rest of the gulf in Nayarit and Sonora ( Fraser 1938c, 1948). In the MP, it has been recorded off the coasts of Jalisco and Guerrero ( Fraser 1938a, 1938c).

Figures

Figure 6. (A–C) Aglaophenia pinguis Fraser,1938; A, hydrocaulus; B, hydrotheca; C, hydrotheca inferior nematotheca. (D–F) Aglaophenia symmetrica Fraser, 1938: D, hydrocaulus; E, hydrotheca; F, hydrotheca inferior nematotheca. (G–I) Macrorhynchia philippina Kirchenpauer, 1872: G, hydrocaulus; H, hydranth; I, hydrotheca inferior nematotheca. (J, K) Halopteris violae Calder, Mallinson, Collins and Hickman, 2003; J, hydrocaulus; K, hydrotheca. Scale bars: A, J = 500 μm; B, E, G, H, K = 200 μm; C, F, I = 100 μm; D = 1 cm. Drawings made by Nicholas Bezio.