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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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This content will become publicly available on July 1, 2026
Prorocentrum insidiosum sp. nov. (Prorocentrales, Dinophyceae): Morphological and Phylogenetic Characterization of a Mucosphere Producing Dinoflagellate From the “ cordatum Group”
ABSTRACT Prorocentrumcf.balticumwas the provisional designation assigned to strains of a small, pelagic, mixoplanktonic dinoflagellate found to produce carbon‐rich mucilage‐based prey capture devices, termed “mucospheres.” Here we characterize the morphology and phylogeny of the strains, describe them asProrocentrum insidiosumsp. nov., and discuss common morphological features among the six species of the phylogenetically definedP. cordatumgroup. Cells ofP. insidiosumsp. nov. were round to slightly ovate in lateral view, 12–16 μm long and 8–15 μm deep, and laterally compressed. Scanning electron microscopy revealed the thecal plates were densely ornamented with short spines and there were two size classes of pores irregularly distributed across both plates, and a row of two to four large round pores in apical‐ventral position on the right thecal plate. The periflagellar area consisted of eight platelets, and there were two prominent wing‐like apical projections in the form of a double layered curved structure on platelet 1 with additional projections on most other platelets except platelet 4.Prorocentrum insidiosumsp. nov. is distinct from all genetically represented species within the genus and possesses a unique combination of morphological features differentiating it from other protologues of smallProrocentrumspecies.
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- Award ID(s):
- 2140395
- PAR ID:
- 10648539
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Eukaryotic Microbiology
- Volume:
- 72
- Issue:
- 4
- ISSN:
- 1066-5234
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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