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The Gelidiales comprises economically valuable species of marine red algae that are found globally, in cold, temperate, and warm waters. Although there is much known about the species diversity and distribution of this order, it remains underexplored on the temperate coast of the Southwestern Atlantic Ocean. This study aimed to update current knowledge about the intertidal Gelidiaceae found on the temperate coast of Argentina using a combination of rbcL data and morpho-anatomical studies and to evaluate the morphological variability among species related to habitat characteristics. Three morphotypes were found at the six localities surveyed; two were identified as different morphologies of Gelidium crinale and one was identified as Gelidium carolinianum. Populations of both species were widespread and coexisted extensively from 37° S to 40° S along the Argentinean coast. G. carolinianum is newly reported in the Southern Hemisphere, indicating it has a disjunct distribution that includes the North Atlantic and Mediterranean as well. Molecular data confirmed previous reports of G. crinale in Argentina, a species that exhibited broad morphological variability among sites. The development of both spermatangia and carpogonia on the same fertile gametophyte thalli in G. crinale and G. carolinianum was described for the first time and demonstrated that they are monoecious. These findings shed light on the diversity and biogeography of Gelidiales from temperate South America. [ABSTRACT FROM AUTHOR]

Abstract: Detailed morphological and rbcL sequence analyses are presented for two species of Gelidium collected along the Pacific coast of Costa Rica. Although relatively well known in the tropical eastern [...]

Since the description of Peromyscus leucopus easti Paradiso, 1960, scant work has been directed toward examining the evolutionary relationships of P. leucopus in the mid-Atlantic region. We used morphometric and molecular analyses to examine the phylogenetic relationships of 3 subspecies known from the eastern United States (P. l. easti, P. l. leucopus, and P. l. noveboracensis); additional specimens from North and South Dakota (P. l. aridulus) were incorporated in the molecular analysis. Morphometric analyses revealed that large mice are found in New England and the Appalachian Mountains as far south as west-central North Carolina and that intermediate-sized mice inhabit the Cumberland Plateau and the lowlands from Virginia southward at least to Alabama. These groups represent P. l. noveboracensis and P. l. leucopus, respectively. The smallest specimens, which are referable to P. l. easti, were found in the vicinity of Princess Anne County, Virginia. The largest mice were found on the southern half of Hatteras Island, North Carolina. Examination of D-loop sequence data revealed that there is no apparent restriction of gene flow among P. leucopus on the mainland of the eastern United States, including those from Princess Anne County, Virginia. However, mice from the southern end of Hatteras Island, North Carolina, were as distinct from specimens from the eastern United States as were mice from North and South Dakota. The population of white-footed mice from Hatteras Island, North Carolina, represents an undescribed subspecies. Key words: mid-Atlantic region, new subspecies, Peromyscus leucopus, systematics, white-footed mouse

Abstract The endemic seagrass Halophila hawaiiana Doty & Stone is found in discrete populations throughout the Hawaiian Archipelago. Morphological characteristics of plants from Midway Atoll, Pearl and Hermes Reef, Kaua'i, [...]

Complete and/or partial DNA sequences for the plastid-encoded rbcL gene and the 5′ end of the mitochondrial cytochrome oxidase I (COI-5P) gene were used to re-examine the systematics of Hypnea species (Cystocloniaceae, Rhodophyta) from North Carolina, USA. These data, combined with light microscopic observations, indicate that two species (Hypnea cryptica and H. musciformis sensu stricto) are present in nearshore waters of coastal North Carolina. Molecular and morphological analyses with topotype material of Hypnea volubilis from North Carolina offshore waters revealed that it and Calliblepharis saidana are conspecific. Hypnea volubilis is proposed as a heterotypic synonym of C. saidana. This is the first report of Calliblepharis from the United States Atlantic coast and only the second report from the western hemisphere. [ABSTRACT FROM AUTHOR]

The Caribbean spiny lobster, Panulirus argus, is distributed from Brazil throughout the Caribbean and the Gulf of Mexico to approximately North Carolina and Bermuda (Holthius, 1991). It supports major commercial [...]

Polysiphoniais the largest genus of red algae, and several schemes subdividing it into smaller taxa have been proposed since its original description. Most of these proposals were not generally accepted, and currently the tribe Polysiphonieae consists of the large genusPolysiphonia(190 species), the segregate genusNeosiphonia(43 species) and 13 smaller genera (< 10 species each). In this paper, phylogenetic relationships of the tribe Polysiphonieae are analysed, with particular emphasis on the generaCarradoriella, Fernandosiphonia, Melanothamnus, Neosiphonia, Polysiphonia sensu stricto,StreblocladiaandVertebrata. We evaluated the consistency of 14 selected morphological characters in the identified clades. Based on molecular phylogenetic (rbcL and 18S genes) and morphological evidence, two speciose genera are recognized:Vertebrata(including the type species of the generaCtenosiphonia, Enelittosiphonia, BoergeseniellaandBrongniartella) andMelanothamnus(including the type species of the generaFernandosiphoniaandNeosiphonia). Both genera are distinguished from other members of the Polysiphonieae by synapomorphic characters, the emergence of which could have provided evolutionarily selective advantages for these two lineages. InVertebratatrichoblast cells are multinucleate, possibly associated with the development of extraordinarily long photoprotective trichoblasts.Melanothamnushas 3-celled carpogonial branches and plastids lying exclusively on radial walls of the pericentral cells, which similarly may improve resistance to damage caused by excessive light. Other relevant characters that are constant in each genus are also shared with other clades. The evolutionary origin of the generaMelanothamnusandVertebratais estimated as 75.7–95.78 and 90.7–138.66 Ma, respectively. Despite arising in the Cretaceous, before the closure of the Tethys Seaway,Melanothamnusis a predominantly Indo-Pacific genus and its near-absence from the north-eastern Atlantic is enigmatic. The nomenclatural implications of this work are that 46 species are here transferred toMelanothamnus, six species are transferred toVertebrata, and 13 names are resurrected forVertebrata. [ABSTRACT FROM PUBLISHER]