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Lobophorais a common tropical to temperate genus of brown algae found in a plethora of habitats including shallow and deep‐water coral reefs, rocky shores, mangroves, seagrass beds, and rhodoliths beds. Recent molecular studies have revealed thatLobophoraspecies diversity has been severely underestimated. Current estimates of the species numbers range from 100 to 140 species with a suggested center of diversity in the Central Indo‐Pacific. This study used three molecular markers (cox3,rbcL,psbA), different single‐marker species delimitation methods (GMYC,ABGD,PTP), and morphological evidence to evaluateLobophoraspecies diversity in the Western Atlantic and the Eastern Pacific oceans.Cox3 provided the greatest number of primary species hypotheses(PSH), followed byrbcL and thenpsbA.GMYCspecies delimitation analysis was the most conservative across all three markers, followed byPTP, and then ABGD. The most informative diagnostic morphological characters were thallus thickness and number of cell layers in both the medulla and the dorsal/ventral cortices. Following a consensus approach, 14 distinctLobophoraspecies were identified in the Western Atlantic and five in the Eastern Pacific. Eight new species from these two oceans were herein described:L. adpressasp. nov.,L. cocoensissp. nov.,L. colombianasp. nov.,L. crispatasp. nov.,L. delicatasp. nov.,L. dispersasp. nov.,L. panamensissp. nov., andL. tortugensissp. nov. This study showed that the best approach to confidently identifyLobophoraspecies is to analyzeDNAsequences (preferablycox3 andrbcL) followed by comparative morphological and geographical assessment.
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Paludicola gen. nov. and Revision of the Species Formerly in Batrachospermum Section Turfosa (Batrachospermales, Rhodophyta)
Since the first phylogenetic study of the order Batrachospermales,Batrachospermumwas shown to be paraphyletic. Subsequently, sections of the genus have been methodically investigated usingDNAsequences and morphology in order to propose new genera and delineate species.BatrachospermumsectionTurfosais the last section with multiple species yet to be examined. New sequence data of specimens from Europe and the United States were combined with the sparse sequence data already available. Phylogenetic analyses usingrbcL andCOI‐5P sequences showed this section to be a well‐supported clade, distinct fromBatrachospermumsectionBatrachospermumand its segregate genera. Section Turfosais raised to the generic rank asPaludicolagen. nov. Substantial genetic variation within the genus was discovered and 12 species are recognized based onDNAsequence data as well as morphological characters and geographic distribution. The following morphological characters were applied to distinguish species: branching pattern (pseudodichotomous or irregular), whorl size (reduced or well developed), primary fascicles (curved or straight), spermatangia origin (primary or secondary fascicles), and carposporophyte arrangement (loose or dense). Previously published species were transferred to the new genus:P. turfosa,P. keratophyta,P. orthosticha,P. phangiae,andP. periploca. Seven new species are proposed as follows:P. groenbladiifrom Europe;P. communis,P. johnhallii, andP. leafensisfrom North America; andP. aquanigra,P. diamantinensis, andP. turfosiformisfrom Brazil. In addition, three unsequenced species in the section,P. bakarensis,P. gombakensis, andP. tapirensis, were transferred to the new genus.
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- PAR ID:
- 10456358
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Phycology
- Volume:
- 56
- Issue:
- 4
- ISSN:
- 0022-3646
- Page Range / eLocation ID:
- p. 844-861
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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