Udotea dotyi D.S. Littler & M.M. Littler 1990: 223

Acosta-Calderón, Julio Adulfo, Hernández-Rodríguez, César, Mendoza-González, Ángela Catalina & Mateo-Cid, Luz Elena, 2018, Diversity and distribution of Udotea genus J. V. Lamouroux (Chlorophyta, Udoteaceae) in the Yucatan peninsula littoral, Mexico, Phytotaxa 345 (3), pp. 179-218 : 199

Udotea dotyi D.S. Littler & M.M. Littler 1990: 223

Type Locality:— GRENADINES. Lesser Antilles, Tobago Cays.

Morphology: — Thalli to 11 cm tall, anchored to the substrata by a bulbous mass of rhizoids. Stipe flattened and robust, 8–13 mm length, 3–5 mm diameter, there is no differentiation between the stipe and blade. Blade fan-shaped, occasionally lobed, green, slightly longer (7–10 cm) than wider (6–7.5 cm), lower margin ovate or truncate, multistratose, corticate, heavily calcified, and faint concentric zonation (Fig. 41).

Anatomy:—Blade siphons with lateral appendages, 20–40 μm in diameter, densely covered by two opposite rows of short lateral appendages (Fig. 42) with irregular flat apices, blade appendages peduncle 15–30 μm in diameter, 60–120 μm length ( Fig. 43 ). Stipe siphons adjacent to lateral appendages 40–70 μm in diameter, appendages peduncle 150–300 μm length, 20–40 μm in diameter. Appendages branched twice, terminating in numerous blunt rounded tips ( Fig. 44 ).

Reproduction: — The terminal portions of the blade siphons are transformed into sexual reproductive organs named gametangia.

Material examined: — MEXICO. Quintana Roo, Uvero, 20 June 2010, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23133. MEXICO. Campeche, Xpicob, 25 June 2016, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23132.

Geographic distribution: — Honduras, Panama, Cuba, Haiti, Lesser Antilles, Puerto Rico, Mexico.

Habitat: — Sandy bottom with sea grass. Subtidal to 3 m depth.

Comments:— Udotea dotyi can be confused with U. flabellum because both possess a corticated fan-shaped blade, but the arrangement and shape of the blade’s lateral appendages are clearly different between these species. On the other hand, U. dotyi and U. dixonii possess blade siphons covered with two rows of lateral appendages, nevertheless the shape of the blade’s lateral appendages is different. The shape of the blade and stipe appendages agrees with those described by Littler & Littler (1990). The diameter of blade and stipe siphons is less than those recorded in specimens from Haiti and Honduras ( Littler & Littler 1990), buy are like those recorded in algae from Quintana Roo, Mexico ( Collado-Vides et al. 2009). Udotea dotyi was an uncommon species in the study area and is recorded for the first time for the Campeche littoral.

Figures

FIGURES 43–44. U. dotyi. 43) blade lateral appendages, 44) stipe lateral appendages. FIGURES 45–49. U. fibrosa. 45–46) external morphology, 47) blade siphons, 48) detail of the supradichotomic constriction of the blade siphon, 49) stipe lateral appendages. FIGURES 50–51. U. flabellum. 50–51) external morphology.