Udotea cyathiformis f. sublittoralis (W.R. Taylor) D.S. Littler & M.M. Littler 1990: 216

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 : 196

Udotea cyathiformis f. sublittoralis (W.R. Taylor) D.S. Littler & M.M. Littler 1990: 216

Basionym:— Udotea sublittoralis W.R. Taylor 1928: 91

Type Locality:— USA. Florida, Garden Key, Dry Tortugas.

Morphology:—Thalli to 12 cm tall, anchored on substrata by a compact rhizoidal mass. Stipe cylindrical 5–47 mm length, 3–6 mm diameter and flattening towards the blade. Evident transition between the stipe and blade. Spatulate blade, green, longer (1–8 cm) than wider (1.5–5 cm), lower margin ovate, multistratose, ecorticate, calcified, and lightly zonate (Figs. 26, 27).

Anatomy: — Blade siphons without lateral appendages, dichotomously branched, 40–80 μm in diameter, distance between each dichotomy ranges from 1200 to 1900 μm (Fig. 28), supra dichotomous constrictions 18–30 μm length, 10–20 μm in diameter (Fig. 29). Stipe siphons adjacent to lateral appendages 40–70 μm in diameter, appendages peduncle 150–200 μm length, 25–40 μm in diameter. Appendages dichotomously branched 2–3 times, with short swollen and flattened apices (Fig. 30).

Reproduction: — Vegetative.

Material examined:— MEXICO. Quintana Roo, Santa Rosa, 11 June 2014, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23100. MEXICO. Quintana Roo, Santa Rosa, 9 September 2014, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23105. MEXICO. Quintana Roo, Santa Rosa, 18 December 2014, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23122. MEXICO. Quintana Roo, Isla Mujeres, 16 June 2014, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González ENCB, 23120. MEXICO. Quintana Roo, Rio Indio, 11 September 2014, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23101. MEXICO. Quintana Roo, Punta Akumal, 16 December 2014 J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23121. MEXICO. Quintana Roo, Punta Placer, 13 June 2014, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23106. MEXICO. Quintana Roo, Uvero, 10 June 2014, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23102. MEXICO. Quintana Roo, Punta Mahahual, 20 December 2014, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23104. MEXICO. Quintana Roo, Pulticub, 14 September 2012, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González ENCB 20854. MEXICO. Quintana Roo, Punta Pelicanos, 17 January 2011, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 20707. MEXICO. Campeche, Playa Villamar, 25 January 2016, J. A. Acosta Calderón, L. E. Mateo Cid, A. C. Mendoza González, ENCB 23103.

Geographic distribution: — Florida, Lesser Antilles, Brazil, North Carolina, Belize, Panama, Bahamas, Cuba, Martinique, Puerto Rico, Mexico.

Habitat: — Rocky platforms with soft waves. Subtidal to 2 m depth.

Comments: — Taylor (1928) described for the first time Udotea sublittoralis from specimens with the funnelshaped lamina, not flattened with spongy appearance and with irregularly branched lateral appendages and folded or truncated apices. However, Littler & Littler (1990) considered that those specimens corresponding to U. sublittoralis should be considered as a form of the parental species ( U. cyathiformis ), thus, they assigned the name U. cyathiformis f. sublittoralis to those specimens of fibrous and cup-like appearance. In this work, the shape of the stipe appendages coincides with those described by Taylor (1928) and Littler & Littler (1990), however the blade shape was different from what these authors mention. The diameter of stipe and blade siphons does not match those registered by Taylor (1928) and Littler & Littler (1990). The presence of this taxon is confirmed in the Quintana Roo coast and it is a firsttime record for Campeche shores.