Since Taylor (1960) used Bermuda’s Meredithia crenata to illustrate K. limminghei for his concept of the species in the western Atlantic, subsequent workers may have followed his concept of the species over the past half-century. For example, a specimen from

Puerto Rico published as K. limminghei (Ballantine et al. 2011) is also attributable to Meredithia, being genetically different but most closely related to M. crenata (Saunders unpublished data). As the Bermuda specimens are now a new species in a different genus, it remains uncertain what true K. limminghei looks like at maturity and to what it is related. A sequenced collection from Guadeloupe is necessary to taxonomically understand this poorly known species and to know whether other workers’ concept of the taxon from other Caribbean sites is correct (e.g., Littler and Littler 2000). MK-8669 clinical trial In our genetic analyses, Meredithia crenata PD98059 clustered with M. microphylla, Psaromenia berggrenii (J. Agardh) D’Archino, W.A. Nelson et Zuccarello, Cirrulicarpus nanus, and several novel molecular species of Meredithia and Psaromenia from Korea, the Philippines, Lord Howe Island, Tasmania and Western Australia in a strongly supported clade (Figs. 1 and 2). Our molecular results are thus consistent with our morphological observations in assigning our Bermudian species to

the genus Meredithia. Furthermore, our molecular results corroborate the relationship of M. microphylla, M. crenata, and P. berggrenii in the partial LSU rDNA tree shown by D’Archino et al. (2011) (fig. 2, M. crenata listed as K. limminghei). Meredithia guiryorum G.W. Saunders et C.W. Schneid. sp. nov. (Fig. 6, A and B) Description: Plants in small MCE clusters of simple blades. Individuals stipitate, stipes ~0.5–1.0 mm wide and 1–2 mm tall; blades nonpeltate, irregular in outline, typically taller than wide 1.0–2.5 cm in diameter, not anastomosing(?) (Fig. 6A). Blades 200–270 μm thick in longitudinal section near the margin, composed of a moderately dense filamentous medulla with common, darkly staining stellate medullary cells observed throughout the section (Fig. 6B).

Inner cortex of two to three cell layers, outer cortex with one to two layers of slightly larger (4–5 μm wide, 5.0–7.5 μm tall) versus two to three layers of slightly smaller (2.5–5.0 μm wide, 5–6 μm tall) cells on the ventral and dorsal surfaces respectively (Fig. 6B). Reproduction not observed. Best identified by comparison with the type COI-5P barcode sequence (GenBank: KC157616). Type collection: Coll. G.W. Saunders (GWS)/K. Dixon (KD)/R. Withall (RW), November 23, 2010, North Head Gutters, Lord Howe, I., Australia, 31.52439° S, 159.04204° E, depth 15 m on rock. Holotype, UNB [GWS023256, BOLD OZSEA1125-10] (Fig. 6, A and B). Isotypes, UNB [GWS023196, GWS023198, GWS023199, GWS023220]. Additional collections (Paratypes): Listed in Table 1.