Eudendrium capillare Alder, 1856

Mendoza-Becerril, María A., Estrada-González, Mariae C., Mazariegos-Villarreal, Alejandra, Restrepo-Avendaño, Luisa, Villar-Beltrán, Rogelio D., Agüero, José & Cunha, Amanda F., 2020, Taxonomy and diversity of Hydrozoa (Cnidaria, Medusozoa) of La Paz Bay, Gulf of California, Zootaxa 4808 (1), pp. 1-37 : 10

Eudendrium capillare Alder, 1856

Figs. 4 B–E

Eudendrium capillare Alder 1856: 355 , pl. 12, figs. 9–12.

Eudendrium tenue Agassiz 1865: 160 , fig. 250.— Fraser 1938a: 20.— Fraser 1938b: 109.— Fraser 1948: 199.

Type locality. Embleton Bay , Northumberland, Great Britain ( Alder 1856) .

Material examined. Polyp—PB6_8, sampling site 3 (1), mature, male, on rock, Bryozoa, and Polychaeta.

Description. Colony small (4 mm high), stolonal and erect, monosiphonic, arising from creeping hydrorhiza, hydrocaulus alternately branched. Exoskeleton with visible layer corresponding to perisarc. Perisarc thin (2.8–4.6 µm wide), annulated at the base of the hydrocaulus and branches. Hydranths urn-shaped (0.4 mm long from base to hypostome, 0.3 mm wide) with proximal perisarc groove; gastroderm with black pigment spots, without ring of nematocysts above the perisarc groove. Hypostome large, knob-shaped; one whorl of 19–24 solid and filiform tentacles. Male gonophores as fixed sporosacs, with up to three chambers each, on reduced hydranths.

Nematocysts (length x diam.). Heterotrichous microbasic eurytele (7.2–9.7 x 3.4–4.2 µm).

More detailed description in Calder (1988) and Marques (2001).

Taxonomic status. Accepted. AphiaID 117544.

Remarks. This species is differentiated from Eudendrium ramosum ( Linnaeus, 1758) based on the size of the heterotrichous microbasic euryteles, which are larger in E. ramosum (24.7–33.0 µm long, 10.8–17.4 µm wide) ( Marques 2001).

Distribution. Species frequently distributed in warm waters of the Atlantic, Indian, and Pacific oceans ( Calder 1988; Marques 2001). In Mexican Pacific, the species was reported in Baja California (Cedros Island and Isla Partida) ( Fraser 1938b; Fraser 1948), Baja California Sur (San Juanico Bay and Dewey Channel) ( Fraser 1948), Colima (Clarion Island) ( Fraser 1938a; Fraser 1948) and Guerrero (White Friars Islands) ( Fraser 1938a).

Figures

FIGURE 4. A Bimeria vestita Wright, 1859: pseudohydrotheca. B–E Eudendrium capillare Alder, 1856: B, colony; C, hydranths; D, male gonophore; E, nematocyst heterotrichous microbasic eurytele. F–M Aglaophenia sp. Fraser, 1938b: F, hydrocaulus; G–H, hydrocladia; I–J, hydrotheca with nematothecae; K, corbula; L, nematocyst microbasic mastigophore; M, colony. Scale equals A—100 µm; B, K—500 µm; C—250 µm; D, H—220 µm; E—11 µm; F—300 µm; G—200 µm; I—50 µm; J—70 µm; L—20 µm; M—5 mm.