Biodiversidad de algas epizoicas en el Pacífico tropical mexicano

Background and Aims: Although the phycological knowledge for the Mexican Pacific region is broad, most studies have been oriented to know the flora adhered to rocky substrates. However, the number of works on macroalgae that grow on living organisms, such as epizoics, is limited. The purpose of this paper is to contribute to the knowledge of epizoic algal flora in the Mexican tropical Pacific.Methods: Four samplings of the mollusk Chiton articulatus were carried out in two locations in Guerrero, Mexico, during 2014, to know the algae that grow on it. Furthermore, a literature review of studies in the Mexican tropical Pacific was carried out to obtain the records of the algae that grow on animals. Finally, algae on molluscs were determined by observations of complete thallus and sections.Key results: A total of 124 species, 81 genera, 51 families and 27 orders was reported, distributed in four algae divisions. The orders with the highest specific richness were Ceramiales (23) and Corallinales (20), and the families with the highest number of species were Rhodomelaceae (13), Cladophoraceae (11) and Lithophyllaceae (10). The most diverse genera were Amphiroa and Cladophora (7). For Guerrero, 12 new species records are presented, of which three are also new records for the Mexican tropical Pacific and three for the Mexican Pacific. The state with the highest number of recorded species was Guerrero (58). The most common substrate was mollusks. The predominant algal morphofunctional group were the filaments.Conclusions: The results of this work demonstrate that the biodiversity of algae present on animal substrates is high, contributing significantly to the specific richness recorded for Guerrero and the Mexican Pacific. The importance of developing more studies that focus on knowledge of algal epibiosis is evident.Antecedentes y Objetivos: El conocimiento ficológico para la región del Pacífico mexicano es amplio, la mayoría de los estudios han estado orientados a conocer la flora adherida a sustratos rocosos. Sin embargo, es reducido el número de trabajos acerca de macroalgas que crecen sobre organismos vivos, como las algas epizoicas. El presente trabajo tiene como finalidad contribuir al conocimiento de la flora algal epizoica en el Pacífico tropical mexicano. Métodos: Se llevaron a cabo cuatro muestreos del molusco Chiton articulatus en dos localidades de Guerrero, México, durante 2014, para conocer las algas que crecen sobre él. Además, se realizó una revisión bibliográfica de estudios en el Pacífico tropical mexicano para obtener los registros de las algas que crecen sobre animales. Finalmente, se determinaron las algas en los moluscos mediante observaciones de talos completos y cortes. Resultados clave: En total se reportaron 124 especies, 81 géneros, 51 familias y 27 órdenes, distribuidos en cuatro divisiones de algas. Los órdenes con mayor riqueza específica fueron Ceramiales (23) y Corallinales (20) y las familias con mayor número de especies fueron Rhodomelaceae (13), Cladophoraceae (11) y Lithophyllaceae (10). Los géneros más diversos fueron Amphiroa y Cladophora (7). Se presentan, para Guerrero, 12 nuevos registros de especies, de los cuales tres son además nuevos registros para el Pacífico tropical mexicano y tres para el Pacífico de México. El estado con mayor número de especies registradas fue Guerrero (58). El sustrato más común fueron los moluscos. El grupo morfofuncional algal predominante fue los filamentos.Conclusiones: Los resultados de este trabajo demuestran que la biodiversidad de algas presente en los sustratos animales es alta, y contribuye notablemente a la riqueza específica registrada para Guerrero y para el Pacífico de México. Se hace patente la importancia de desarrollar más estudios que se enfoquen al conocimiento de la epibiosis algal

Chaetognath assemblages in Bahia de Banderas, Mexico

The composition, distribution, and main assemblages of chaetognath species were examined throughout an annual cycle in Bahia de Banderas, Mexico. Zooplankton sampling was carried out during five seasons (1989 and 1991), using a 50 cm diameter and 1.5 m long conical net with a 505 pm mesh size. The abundance of chaetognaths in each season was subjected to a Factor Correspondence Analysis (FCA) in order to identify the main assemblages. A total of 4142 individuals was sorted out from samples, and seven species were identified: Sagitta euneritica (Alvarino, 1961), Sagitta neglecta Aida, 1897, Sagitta inflata Grassi, 1881, Sagitta bedoti Beraneck, 1895, Sagitta pacifica (Tokioka, 1940), Sagitta minima Grassi, 1881, and Krohnitta pacifica (Aida, 1897). Sagitta euneritica was the most abundant and widely distributed species throughout the study area. The FCA defined two chaetognath groups, the "euneritic assemblage" and the "mixed assemblage," whose differences were established mainly by relative species abundance, rather than composition. For most of the year, the "euneritic assemblage" occupied the area over the shelf, possibly reflecting an area of high secondary production

Lists of Shiphonophores, Polychaetes, Decapods and Chaetognaths in the Gulf of California, Mexico

This work is part of the results of the research of the Laboratory of Invertebrates of the Facultad de Ciencias UNAM, partially financed by the Comision Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO) developing during 2006-2007. The purpose is contributed to knowledge of the biodiversity of the complex pelagic community that lives in the Gulf of California. Faunistics lists of sorting material from 175 samples taking of the epipelagic region during four oceanographics cruseis (AA7704, AA7802, AA7810 and GOLCA8404), including siphonophores, polychaetes, decapods and chaetognaths are present. A total of 97.963 specimens (or zooids, in case of the siphonophores). were identified, which 10,821 were siphonophores, 30,894 polychaetes, 4,314 decapods and 5 1,934 chaetognaths. These lists include 9 orders. 31 families, 9 genera and 56 species