A First Estimate of Species Diversity for Benthic Diatom Assemblages from the Revillagigedo Archipelago, Mexico

Recent investigations at previously unexplored localities on the Mexican coast have confirmed the high taxonomic potential of benthic marine diatom assemblages (BMDA) in the region. An exploratory study of epiphytic diatoms of macroalgae in the Revillagigedo Archipelago (RA) suggested that further studies would yield many more taxa, prompting the hypothesis that diversity measurements, based on ecological indices, would be among the highest in pristine environments. Thus, the aim of this research was to enrich the record of epiphytic diatom floristics of the RA, and to estimate species diversity based on information theory (H′). Floristically, 167 identified taxa are added here to the BMDA species list of the RA, bringing the total to 397 taxa overall, including 52 taxa that are potentially new records for the Mexican Pacific coast. Among the most conspicuous genera are Mastogloia with five new taxa and it remains the most diverse genus with 55 taxa overall, followed by Cocconeis (27), Nitzschia (24), Amphora (23), Navicula (19), Diploneis (17) and Grammatophora (15). As expected for a pristine environment, the computed species diversity values for the BMDA were high, ranging from H′ = 3.92–5.2, depicting stability. Future surveys are expected to further increase the species richness of BMDA for the RA.

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New species of the gorgoniian genus Pacifigorgia (Coelenterata: Octocorallia: Gorgoniidae) from Pacific Panama

Zootaxa ◽

10.11646/zootaxa.541.1.1 ◽

2004 ◽

Vol 541 (1) ◽

pp. 1 ◽

Cited By ~ 10

Author(s):

ODALISCA BREEDY ◽

HECTOR M. GUZMAN

Keyword(s):

New Species ◽

National Park ◽

Pacific Coast ◽

New Records ◽

Scanning Electron Micrographs ◽

Species List ◽

The Pacific ◽

Fourth Species ◽

Shallow Water Species ◽

Water Species

Four new shallow water species of the genus Pacifigorgia were found in recent surveys along the Pacific coast of Panama. One of the species was only found in dense patches at two shallow seamount-like localities inside the Coiba National Park, Gulf of Chiriqu . Two other species were patchily distributed at several localities in the Gulf of Chiriqu . A fourth species was widely distributed around the gulfs of Chiriqu and Panama encompassing a broad range of habitats and depths. The new species are described and illustrated in detail with scanning electron micrographs (SEM) of the sclerites, and colour photographs of the colony forms. The suspected occurrence of a particular Pacifigorgia species for this region is confirmed and two other new records are added to the species list. With the new four species, a total of 15 are established for Panama, making 31 species for the eastern Pacific to date.

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FLORÍSTICA DE DIATOMEAS EPIFITAS EN UN MANCHÓN DE MACROALGAS SUBTROPICALES

CICIMAR Oceánides ◽

10.37543/oceanides.v21i1-2.25 ◽

2006 ◽

Vol 21 (1-2) ◽

pp. 11

Author(s):

D. A. Siqueiros Beltrones ◽

O. U. Hernández Almeida

Keyword(s):

Species Richness ◽

Species Composition ◽

New Records ◽

Diatom Assemblages ◽

Epiphytic Diatoms

Se determinó la composición de especies de diatomeas epifitas en macroalgas de distintos taxa en una zona subtropical. Para ello, en un manchón ubicado en la playa Punta Roca Caimancito, B. C. S., se tomaron muestras de las macroalgas sobresalientes, en junio y diciembre de 2001, y abril, mayo y julio del 2002. Se identificaron 13 especies de macroalgas, de las cuales: Hydroclathrus clathrathus, Laurencia pacifica, L. johnstonii, Padina mexicana, P. caulescens y Codium spp. fueron las más conspicuas. El examen de la flora epifítica redituó 278 taxa de diatomeas, que es la máxima riqueza registrada para este tipo de sustrato, y de los cuales 44 son nuevos registros para la región. De los 75 géneros reconocidos de diatomeas, los mejor representados fueron: Mastogloia (25 especies), Amphora (23), Navicula (23), Nitzschia (22), Cocconeis (22), Lyrella (12) y Achnanthes (11). Los taxa más abundantes fueron Cocconeis disculus y C. dirupta. El número de taxa de diatomeas por especie hospedera también fue alto y varió entre 89 ( Codium spp.) y 143 ( L. pacifica), aunque las diferencias podrían deberse al número de especímenes procesados por especie de macroalga. Floristics of epiphytic diatoms in a patch of subtropical macroalgae The species composition of epiphytic diatom assemblages found on different taxa of subtropical macroalgae was determined. Samplings were carried out in a macroalgae bed located in Punta Roca Caimancito beach, B. C. S. in june and december 2001, and on april, may and july 2002, collecting the most frequent macroalgae taxa. The most conspicuous out of twelve macroalgae taxa were: Hydroclathrus clathrathus, Laurencia pacifica, L. johnstonii, Padina mexicana and P. caulescens. A total of 278 diatom taxa were recorded. This is the largest species richness recorded for this type of substrate, and out of which 44 are new records for the region. Out of 75 genera recognized the best represented were: Mastogloia (25 species), Amphora (23), Navicula (23), Nitzschia (22), Cocconeis (22), Lyrella (12) and Achnanthes (11). The most abundant taxa were Cocconeis disculus and C. dirupta. The number of diatom taxa per macroalgae species was also high, ranging from 89 (Codium spp.) to 143 (L. pacifica). Albeit, this difference could be attributed to the number of specimens collected per macroalga species.

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New records of benthic hydroids (Cnidaria: Hydrozoa) from the coast of Oaxaca, Mexico

Zootaxa ◽

10.11646/zootaxa.4455.3.3 ◽

2018 ◽

Vol 4455 (3) ◽

pp. 454 ◽

Cited By ~ 1

Author(s):

KARLA J. HUMARA-GIL ◽

CHRISTOPHER CRUZ-GÓMEZ

Keyword(s):

Pacific Coast ◽

New Records ◽

Mexican Pacific ◽

Geographic Ranges ◽

The Pacific

Hydroids of the Pacific coast of Mexico have been little studied. For the coast of Oaxaca, only five papers provide information on species of the region, with some records included in those publications being questionable. Seven species, Pennaria disticha, Clytia linearis, Clytia cf. gracilis, Obelia dichotoma, Ventromma halecioides, Dynamena crisioides and Tridentata turbinata, were discovered during the study and are reported herein. Of these species, Pennaria disticha and Tridentata turbinata are new records for the Mexican Pacific coast, and Clytia linearis and Ventromma halecioides are new records for Oaxaca. Geographic ranges of other hydroids, recorded in earlier studies, are expanded.

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Chrysopetalids (Phyllodocida: Chrysopetalidae) from the southern Mexican Pacific, including a new species

Zootaxa ◽

10.11646/zootaxa.4521.1.3 ◽

2018 ◽

Vol 4521 (1) ◽

pp. 61 ◽

Cited By ~ 1

Author(s):

CHRISTOPHER CRUZ-GÓMEZ ◽

J. ROLANDO BASTIDA-ZAVALA

Keyword(s):

New Species ◽

Pacific Coast ◽

New Records ◽

Eastern Pacific ◽

Tropical Eastern Pacific ◽

Mexican Pacific ◽

The Pacific ◽

The Family ◽

First Time ◽

A New Species

The family Chrysopetalidae has been poorly studied from the Pacific coast of Mexico compared to other families. Specifically from the southern Mexican Pacific, only two species of the family have been recorded in previous studies, Chrysopetalum occidentale and Paleanotus chrysolepis. In this study 311 specimens were revised, and nine species, belonging to six genera were found. Eight of these species are new records from the southern Mexican Pacific coast: Arichlidon watsonae n. sp., Bhawania cf. goodei, Chrysopetalum elegantoides, C. maculata, Hyalopale sp., Paleaequor psamathe, Paleanotus bellis and P. purpurea. A new species is also described, Arichlidon watsonae n. sp., which is characterized by the curved tips blades of the falcigers and their small and ovoid palps. Additionally, the genera Arichlidon and Hyalopale are recorded by first time from the Tropical Eastern Pacific.

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Two new endemic species of Gorgoniidae (Cnidaria, Anthozoa, Octocorallia) from Revillagigedo Archipelago, Mexico

Zootaxa ◽

10.11646/zootaxa.4442.4.2 ◽

2018 ◽

Vol 4442 (4) ◽

pp. 523 ◽

Cited By ~ 2

Author(s):

URSULA OLVERA ◽

OSVALDO HERNÁNDEZ ◽

CARLOS SÁNCHEZ ◽

JAIME GÓMEZ-GUTIÉRREZ

Keyword(s):

Species Diversity ◽

Gulf Of California ◽

Benthic Fauna ◽

Mexican Pacific ◽

Sampling Locations ◽

Close Relationship ◽

Yellow Coloration ◽

Volcanic Islands ◽

Revillagigedo Archipelago ◽

Sea Fan

Two new species of the genera Eugorgia and Leptogorgia were discovered while underwater collecting at the Revillagigedo Archipelago, Mexico. Sea fan species diversity and density population in these four volcanic islands is low (<12 spp.), and the possibility of endemism is high given their isolation from the mainland (403 km southwest of Cabo San Lucas, Baja California peninsula). Morphological features suggest Eugorgia wilkiei sp. nov. has a close relationship to species of the daniana group, particularly with Eugorgia multifida Verrill, 1870. However, E. wilkiei sp. nov. has densely branched irregular-pinnate colonies that grow in several simple planes or multiplanar flabelliform, and shows two distinct chromotypes (yellow or red). Leptogorgia waltonae sp. nov. is added here to the ena group because its similar in size and sclerites to Leptogorgia ena Breedy et al. 2012. However, the wart-like terminal twigs representing an enlargement of the axis (but not the coenenchyme which has the same thickness throughout the colony), 90°-angled lateral branching, and the red, purple, orange, or yellow coloration range of the colonies are the main taxonomic characters to distinguish L. waltonae sp. nov. from L. ena. Scuba diving observations in about 200 sampling locations done since 1995 to 2016 along the mexican Pacific coast, including the Gulf of California, indicate both new octocoral species are distributed only at Revillagigedo islands. Revillagigedo Archipelago is surrounded by oligotrophic oceanic waters, strong seawater currents, and relatively frequent hurricane perturbations that favor small or robust, and hard and resistant sea fan colonies, low-species diversity, and low-population density. These factors may enhance speciation processes supporting the comparatively high endemism of the islands benthic fauna as well.

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PROSPECTIVE FLORISTICS OF EPIPHYTIC DIATOMS ON RHODOPHYTA FROM THE SOUTHERN GULF OF MEXICO

CICIMAR Oceánides ◽

10.37543/oceanides.v32i2.207 ◽

2017 ◽

Vol 32 (2) ◽

pp. 35

Author(s):

David Alfaro Siqueiros Beltrones ◽

Yuriko Joscelin Martínez - Hernández

Keyword(s):

Species Richness ◽

Gulf Of Mexico ◽

Species Composition ◽

Light Microscopy ◽

Red Algae ◽

New Records ◽

Similarity Measurement ◽

Diatom Assemblages ◽

Epiphytic Diatoms ◽

Southern Gulf Of Mexico

Studies on epiphytic diatoms can be considered somewhat lacking worldwide, mainly because of the enormous scientific research potential around them, and there is still much to do concerning floristics alone. Particularly for the Mexican coasts, mainly in the southern Gulf of Mexico. Thus, our objective was to determine the epiphytic diatom floristics for several species of Rhodophyta from the coast of Veracruz state (México). Diatoms sampled from specimens of six taxa of Rhodophyta were observed in permanent mountings, under light microscopy. A total 115 diatom taxa were identified, that support our expectancy of a potential species richness much higher on red algae hosts. A presence absence similarity measurement suggested that a single diatom assemblage was hosted in the six red algae taxa. The species composition is highly similar to epiphytic diatom assemblages from NW Mexico, albeit six taxa are new records for Mexican littorals. A photographic catalog of the identified epiphytic diatoms is provided.Florística prospectiva de diatomeas epifitas sobre Rhodophyta en el Sur del Golfo de México Los estudios sobre diatomeas epifitas a nivel global se pueden considerar escasos, principalmente por el gran potencial científico que representan. Una consecuencia de ello es lo mucho que falta por hacer tan solo en florística a lo largo de las costas mexicanas, particularmente al sur del Golfo de México. Así, el objetivo de nuestro estudio fue determinar la florística de diatomeas epifitas en varias especies de Rhodophyta de la costa del Estado de Veracruz, México. Se identificaron diatomeas epifitas en talos de seis taxa en preparaciones permanentes bajo microscopía de luz. La lista florística de diatomeas redituó 115 taxa, lo que respalda nuestra expectativa de una riqueza de especies potencial mucho mayor en Rhodophyta hospederos. La similitud (Bray-Curtis) con base en presencia/ausencia de taxa sugiere que una sola asociación de diatomeas epifitas se distribuye entre los seis taxa de algas rojas hospederos. La composición de especies es muy similar a la de asociaciones de diatomeas epifitas del NW de México, aunque seis taxa son nuevos registros para litorales mexicanos. Se incluye un catálogo fotográfico de los taxa de diatomeas epifitas identificadas.

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Diatoms in the Early Valdai (Weichselian) sediments in Lake Ladoga basin

Issues of modern algology (Вопросы современной альгологии) ◽

10.33624/2311-0147-2019-2(20)-225-228 ◽

2019 ◽

pp. 225-228

Author(s):

Anna V. Ludikova

Keyword(s):

Species Diversity ◽

High Energy ◽

Lake Ladoga ◽

Diatom Assemblages ◽

Marine Diatoms ◽

Selective Preservation

The pioneer diatom study of the Early Weichselian (Valdai) sediments in Lake Ladoga basin was performed. The specifics of the diatom assemblages (co-occurrence of ecologically incompatible taxa, poor species diversity, low diatom concentration and selective preservation) suggest that during the Early Weichselian time intense erosion of previously deposited marine Eemian (Mikulino) sediments prevailed, which resulted in re-deposition of marine diatoms. The sedimentation took place in high-energy environments unfavorable for diatom accumulation and preservation.

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