Aglaophenia symmetrica Fraser, 1938

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 : 823-824

Aglaophenia symmetrica Fraser, 1938

( Figure 6D–F )

Material examined

1 colony, polyp, without corbulae; Punta Diablo, La Paz Bay , Baja California Sur, 24.316°N, 110.340°W; depth 9.75 m; 14 September 2017; on coralline algae and rock; ECO-CH-Z 11759 .

Identification (after Fraser 1938b)

Colonies erect, hydrocaulus monosiphonic, alternately branched, divided into internodes by transverse nodes. Internodes with a distal hydrocladial apophysis, a pseudonematotheca, and three cauline nematothecae, one inferior and two axillary on frontal and posterior positions. Hydrocladia unbranched, divided into thecate internodes by slightly oblique distinct nodes. Each internode bearing one hydrotheca, one median inferior nematotheca, and a lateral pair of nematothecae; two internodal septa for internode, one distinct at the base of intrathecal septum, and one indistinct at the base of lateral nematothecae. Hydrothecae with abcauline wall nearly straight distally, hydrothecal margin with nine cusps, one median and four lateral pairs, median abcauline cusp shorter than others, first to third lateral pairs nearly equal in size. Median inferior nematotheca adnate to abcauline wall of hydrotheca basally, reaching the median portion of hydrotheca; lateral reach beyond hydrothecal margin.

Distribution

Previously recorded in Sonora ( Fraser 1938b). The present specimen constitutes the second record within the Gulf of California.

Remarks

The specimen resembles the description of A. symmetrica by Fraser (1938b), mainly in the position of the lower nematotheca and the size of the cusps of the hydrothecal margin. The identity of the specimen was corroborated with photographs of the type specimen, in collections at the Santa Barbara Museum of Natural History , catalogue number SBMNH 347209 .

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.