Halopteris violae Calder, Mallinson, Collins and Hickman, 2003

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 : 825

Halopteris violae Calder, Mallinson, Collins and Hickman, 2003

( Figure 6L, M )

Material examined

2 colonies, polyp, without 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 alga Ceramium sp . And coralline and undetermined algae; ECO-CH-Z 11784 .

Identification (after Calder et al. 2003)

Colonies erect; hydrocaulus alternately branched, monosiphonic, divided into athecate and thecate internodes at irregular intervals by oblique nodes proximally and transverse nodes distally. Athecate internodes with 2–3 nematothecae; thecate internodes with a distal hydrocladial apophysis, a hydrotheca, and 3–6 nematothecae, one median inferior, one pair lateral, and the rest superior far from hydrothecae. Hydrocladia unbranched, divided into athecate and thecate internodes by oblique nodes; athecate internodes with one nematotheca; thecate internodes with a hydrotheca, and three nematothecae, one median inferior and one pair lateral. Hydrothecae with margin entire. Median inferior nematotheca far below hydrotheca; lateral nematothecae on short pedicel.

Distribution

Previously recorded from the west coast of the Gulf of California, Baja California Sur ( Mendoza-Becerril et al. 2020), and the only record for the MP .

Remarks

The specimen conforms to the characteristics of H. violae described by Calder et al. (2003), except for not presenting the majority of two nematothecae per athecate internode in the hydrocladia; only one nematotheca was presented.

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.