Orquídeas de los municipios de Santo Domingo Yanhuitlán y San Pedro y San Pablo Teposcolula, Oaxaca

In Oaxaca the Mixteca Alta region is characterized by its high rates of marginalization, edaphic erosion, and deforestation; but also, because its floristic diversity is known only by some isolated studies and at present there are still areas whose floristic richness had not been documented. Here is present an orchideological inventory of a portion of the Mixteca Alta that has been scarcely explored botanically, which correspond to the municipalities of Santo Domingo Yanhuitlán and San Pedro y San Pablo Teposcolula. Both municipalities are part of Cerros Negro-Yucaño priority terrestrial region and the floristic province of the Tehuacan-Cuicatlan valley, so this study contributes to the knowledge of the biodiversity of both regions. This inventory was based on field work, review of herbarium collections, and literature. Fifty-six species (six of them represented by infraspecific categories) and 26 genera of orchids are reported; most (83.9 %) are of terrestrial/rupicolous habit; twenty are endemic to Mexico, and four are restricted to the limits of Oaxaca. Malaxis reichei and Habenaria macvaughiana are new reports for the flora of Oaxaca; Bletia lilacina, Bletia urbana, Habenaria guadalajarana, and Platanthera brevifolia are new records for the flora of the Tehuacan-Cuicatlan valley. Four species are protected by Mexican laws; Laelia albida, Laelia furfuracea, and Prosthechea karwinskii have ornamental and commercial value, they present abundant populations in the study zone, although in other areas of Oaxaca they face risks due to the extraction for local trade and religious uses.En Oaxaca la región de la Mixteca Alta se caracteriza por sus altas tasas de marginación, erosión edáfica y desforestación, pero también porque su diversidad florística se conoce solo por algunos estudios aislados y en la actualidad persisten áreas cuya riqueza florística no ha sido documentada. Aquí presentamos el inventario orquideológico de un área de la Mixteca Alta que ha sido poco explorada botánicamente, comprendida en los municipios de Santo Domingo Yanhuitlán y San Pedro y San Pablo Teposcolula. Ambos municipios son parte de la región terrestre prioritaria de Cerros Negro-Yucaño y de la provincia florística del valle de Tehuacán-Cuicatlán, por lo que el estudio contribuye al conocimiento de la biodiversidad de ambas regiones. Este inventario se generó mediante trabajo de campo, revisión de colecciones científicas y de literatura. Se reportan 56 especies (seis de ellas representadas por categorías infraespecíficas) y 26 géneros de orquídeas; la mayoría (83.9%) son de hábito terrestre/rupícola; veinte son endémicas de México y cuatro se restringen a los límites de Oaxaca. Malaxis reichei y Habenaria macvaughiana son nuevos reportes para la flora de Oaxaca; Bletia lilacina, Bletia urbana, Habenaria guadalajarana y Platanthera brevifolia son nuevos registros para la flora del valle de Tehuacán-Cuicatlán. Cuatro especies se encuentran protegidas por las leyes mexicanas; Laelia albida, Laelia furfuracea y Prosthechea karwinskii son orquídeas de valor ornamental y comercial, presentan poblaciones abundantes en la zona de estudio, pero en otras regiones de Oaxaca enfrentan riesgos por la extracción para comercio local y usos religiosos

The origin and speciation of orchids

SummaryOrchids constitute one of the most spectacular radiations of flowering plants. However, their origin, spread across the globe, and hotspots of speciation remain uncertain due to the lack of an up-to-date phylogeographic analysis.We present a new Orchidaceae phylogeny based on combined high-throughput and Sanger sequencing data, covering all five subfamilies, 17/22 tribes, 40/49 subtribes, 285/736 genera, and c. 7% (1921) of the 29 524 accepted species, and use it to infer geographic range evolution, diversity, and speciation patterns by adding curated geographical distributions from the World Checklist of Vascular Plants.The orchids' most recent common ancestor is inferred to have lived in Late Cretaceous Laurasia. The modern range of Apostasioideae, which comprises two genera with 16 species from India to northern Australia, is interpreted as relictual, similar to that of numerous other groups that went extinct at higher latitudes following the global climate cooling during the Oligocene. Despite their ancient origin, modern orchid species diversity mainly originated over the last 5 Ma, with the highest speciation rates in Panama and Costa Rica.These results alter our understanding of the geographic origin of orchids, previously proposed as Australian, and pinpoint Central America as a region of recent, explosive speciation

Documentation of the medicinal knowledge of Prosthechea karwinskii in a Mixtec community in Mexico

In Mexico, native orchids are appreciated for their ornamental value and traditional uses and in many indigenous communities they comprise part of a biocultural heritage. The orchid Prosthechea karwinskii (Mart.) J.M.H. Shaw, Orchidaceae, is particularly relevant in this context, although some of its traditional uses have been attributed to a very similar species, P. citrina. A recent study of P. karwinskii reported unknown medicinal and other traditional uses by the Mixtec community in Mexico. Unfortunately, increasing acculturation of indigenous communities has resulted in a loss of the community's traditional knowledge, thus, we herein documented the worldview and practices associated with the medicinal use of P. karwinskii as well as the socioeconomic aspects that characterize the holders of this knowledge. People with this knowledge are mainly indigenous women with little or no schooling, who learned the medicinal practices from family tradition. They use pseudobulbs, leaves, or flowers of the plant to treat coughs (infusions), wounds and burns (poultices), diabetes (tea or chewed), to prevent miscarriages and to assist in childbirth (infusions). These results show a promising future for ethnopharmacological research on P. karwinskii

Three new species of Stelis (Orchidaceae; Pleurothallidinae) from Mexico

Three new species in the genus Stelis (Orchidaceae) are here described and illustrated for the first time: two have been previously mentioned and are published formally here. For each taxon, information is provided about its distribution, habitat, phenology, traits that distinguish it from similar species, and conservation status. A line drawing, photo, and map for the known localities of the three species are provided. Key words: Orchids, Stelis guerrerensis, Stelis kaiae, Stelis lapinerae. Resumen. Se describe e ilustra por primera vez tres nuevas especies en el género Stelis (Orchidaceae): dos habían sido mencionadas previamente como nombres no publicados y aquí son formalmente publicados. Para cada taxon se proporciona información acerca de su distribución, hábitat, fenología, rasgos que la distinguen de especies similares, así como su estatus de conservación. Se proporciona un dibujo a línea, foto y mapa para las localidades conocidas de las tres especies aquí descritas

Diez meses de análisis de las enfermedades en especímenes silvestres de Litopenaeus setiferus en el Sur del Golfo de México

The development of shrimp aquaculture in Mexican coasts of the Gulf of Mexico began to be explored using the Pacific white shrimp Litopenaeus vannamei in the mid 90´s. Many concerns over the risk of disease transmission to the economically important native penaeids, have been the main deterrent for the aquaculture of L. vannamei in the region. Concurrently, more than 10 years of research experience on the aquaculture suitability of the native Litopenaeus setiferus from the Terminos Lagoon, in the Yucatán Peninsula, have been accumulated. The aim of this study was then to determine the seasonal variations of the naturally acquired diseases and the possible detection of exotic pathogens. For this, random subsamples (n~60) of juveniles L. setiferus were collected from monthly captures. In order to detect the widest range of pathogens, including infectious hypodermal and hematopoietic necrosis (IHHNV) and white spot syndrome (WSSV) viruses, both histopathological and molecular methods were employed. Monthly prevalence (%) was calculated for every finding. We were able to detect a total of 16 distinct histological anomalies, most of which the presumptive aetiological agent was readily identified. PCR results for viruses were negative. For some pathogens and symbionts, the prevalence was significantly different between the adult and juvenile populations. Prevalence of diseases tended to be higher in juvenile shrimp than in adults. The results of this study indicated that L. setiferus carry a wide variety of pathogens and symbionts that seem to be endemic to penaeids of the Gulf of Mexico, and those juveniles were more conspicuous to acquire pathogens and symbionts than adults.Durante la década de los 90´s se introdujo el camarón blanco del Pacífico Litopenaeus vannamei a los Estados costeros mexicanos del Golfo de México con fines acuícolas, por lo que desde entonces existe preocupación por la posible introducción de enfermedades que puedan afectar a las poblaciones de camarones nativos. La investigación sobre la domesticación de especies nativas para una acuacultura sustentable se ha realizado por más de 10 años, sin embargo, aún existe escasa información sobre las enfermedades que se presentan de manera natural en estas poblaciones y posible trasfaunación. El presente estudio aborda el problema de las enfermedades encontradas en subpoblaciones de jóvenes y adultos de Litopenaeus setiferus del Área natural protegida Laguna de Términos, estado de Campeche, México. Técnicas de histología y biología molecular fueron utilizadas como herramientas de diagnóstico. Se encontró que L. setiferus es portador de patógenos y simbiontes endémicos del Golfo de México, y comparativamente, los jóvenes son más susceptibles en adquirir estas infecciones que los adultos, como probable respuesta al ambiente lacustre que ocupan. No se encontró evidencia de los virus IHHNV y WSSV, aunque en trabajos más recientes en algunos Estados del Norte ya se han detectado en poblaciones silvestres

A ten-month diseases survey on wild Litopenaeus setiferus (Decapoda: Penaeidae) from Southern Gulf of Mexico

The development of shrimp aquaculture in Mexican coasts of the Gulf of Mexico began to be explored using the Pacific white shrimp Litopenaeus vannamei in the mid 90´s. Many concerns over the risk of disease transmission to the economically important native penaeids, have been the main deterrent for the aquaculture of L. vannamei in the region. Concurrently, more than 10 years of research experience on the aquaculture suitability of the native Litopenaeus setiferus from the Terminos Lagoon, in the Yucatán Peninsula, have been accumulated. The aim of this study was then to determine the seasonal variations of the naturally acquired diseases and the possible detection of exotic pathogens. For this, random subsamples (n~60) of juveniles L. setiferus were collected from monthly captures. In order to detect the widest range of pathogens, including infectious hypodermal and hematopoietic necrosis (IHHNv) and white spot syndrome (WSSv) viruses, both histopathological and molecular methods were employed. Monthly prevalence (%) was calculated for every finding. We were able to detect a total of 16 distinct histological anomalies, most of which the presump- tive aetiological agent was readily identified. PCR results for viruses were negative. For some pathogens and symbionts, the prevalence was significantly different between the adult and juvenile populations. Prevalence of diseases tended to be higher in juvenile shrimp than in adults. The results of this study indicated that L. setiferus carry a wide variety of pathogens and symbionts that seem to be endemic to penaeids of the Gulf of Mexico, and those juveniles were more conspicuous to acquire pathogens and symbionts than adults

The complete mitochondrial and plastid genomes of Corallina chilensis (Corallinaceae, Rhodophyta) from Tomales Bay, California, USA

Genomic analysis of the marine alga Corallina chilensis from Tomales Bay, California, USA, resulted in the assembly of its complete mitogenome (GenBank accession number MK598844) and plastid genome (GenBank MK598845). The mitogenome is 25,895 bp in length and contains 50 genes. The plastid genome is 178,350 bp and contains 233 genes. The organellar genomes share a high-level of gene synteny to other Corallinales. Comparison of rbcL and cox1 gene sequences of C. chilensis from Tomales Bay reveals it is identical to three specimens from British Columbia, Canada and very similar to a specimen of C. chilensis from southern California. These genetic data confirm that C. chilensis is distributed in Pacific North America