Multiple spawning and length of embryonic development ofMunida gregariain northern Patagonia (Argentina)

Author(s):  
Fernando G. Dellatorre ◽  
Pedro J. Barón

Munida gregariais a small galatheid widely distributed around the southern hemisphere, considered a key species in food webs of coastal and shelf marine ecosystems. Previous studies conducted at 55°S and 46°S on the Atlantic coast of South America, have shown that the species can adapt its reproductive patterns to different environmental conditions. The objectives of this work are to complete this analysis by determining: (1) the reproductive season span; (2) the potential of the species to produce multiple clutches of eggs; (3) the length of its embryonic development; and (4) based on previous objectives, the potential number of clutches produced byM. gregariaby reproductive season in the northern range of its coastal distribution (42–43°S, northern Patagonia). In this region, brooding females were present from June to December, representing more than 80% of total females between July and October. Females presented previtellogenic oocytes beginning maturation just after egg extrusion, and fully developed vitellogenic oocytes just before hatching. From November to February increasing proportions of females showed signs of athresia and resorption of mature oocytes. The complete embryonic development ofM. gregarialasted 26–29 days at 11ºC constant temperature. Considering the pattern of synchronous ovary re-maturation and embryonic development, the length of embryogenesis at water temperatures typical from costal waters off northern Patagonia during the breeding season, it is concluded that femaleM. gregariahave the potential to consecutively lay more than three egg clutches per reproductive season.

2019 ◽  
Vol 57 (2) ◽  
pp. 400-417 ◽  
Author(s):  
Alexandre Pires Marceniuk ◽  
Tibério Cesar Tortola Burlamaqui ◽  
Claudio Oliveira ◽  
Jeferson Carneiro ◽  
Bruno Eleres Soares ◽  
...  

Zootaxa ◽  
2019 ◽  
Vol 4576 (1) ◽  
pp. 109 ◽  
Author(s):  
ALEXANDRE PIRES MARCENIUK ◽  
RODRIGO ANTUNES CAIRES ◽  
LEONARDO MACHADO ◽  
NAJILA NOLIE CATARINE DANTAS CERQUEIRA ◽  
RAYLA ROBERTA M. DE S. SERRA ◽  
...  

The genus Orthopristis includes seven valid species, three from the western Atlantic and five from eastern Pacific, while the available identification guides and taxonomic keys incorrectly recognize Orthopristis ruber as the only valid species found on the Atlantic coast of South America. Efforts to expand the inventory of fish species from the northern coast of Brazil led to the identification of two distinct species of Orthopristis from Atlantic South America, based on the analysis of coloration patterns and meristic data, as well as DNA. In the present study, the limits of Orthopristis ruber are reviewed, while Orthopristis scapularis is recognized as a valid species for the northern and northeastern coasts of South America. Based on intermediate morphological characteristics and nuclear DNA markers, a hybrid zone was identified off the state of Espírito Santo, on the eastern Brazilian coast. Additionally, considerations are made on the diversity and biogeography of the coastal marine and estuarine fishes found on the Brazilian coast. 


Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mauro N. Tammone ◽  
Ulyses F.J. Pardiñas

Abstract Subterranean rodents Ctenomys are iconic representatives of the mammalian fauna from southern South America. Based on molecular data, eight lineages have been identified within the genus, although species-level identifications and relationships are still debated. Until now, the “magellanicus” clade has been the only lineage mentioned from arid, extra-Andean portions of Patagonia. Here, we report the presence of a Ctenomys population from northern Patagonia that is unambiguously associated with the Central Argentinean “mendocinus” lineage. Most of the 160,000 km2 comprising the northern portion of Patagonia – an area consisting primarily of Monte Desert shrub-land – are inhabited by Ctenomys populations of unknown taxonomy.


2021 ◽  
Author(s):  

Abstract There is little published information on this plant pathogenic fungus, which is limited to parts of North, Central and South America. It infects Rubus spp., which exist in other regions of the world with similar environmental conditions, therefore this species may pose a threat to native or agricultural plants if introduced.


2021 ◽  
Author(s):  
Shane C. Miller ◽  
Diana P Baumann ◽  
M. Shane Merryman

The starlet sea anemone (Nematostella vectensis) is an emerging model organism, and we have maintained a colony at the Stowers Institute since 2007. Nematostella are known as a simple sea anemone, related to other cnidarians such as jellyfish and corals. Native to estuarine environments across the Atlantic coast of North America, from Novia Scotia to Florida, they encounter a variety of environmental conditions (e.g., temperature, salinity). Acknowledging that husbandry conditions and environmental parameters can impact research results we provide information about the housing, nutrition, maintenance, and health for our colony of Nematostella. This information will be applicable to any Nematostella housed in the facility in 2021.


2011 ◽  
Vol 9 (3) ◽  
pp. 571-578 ◽  
Author(s):  
Oscar Lasso-Alcalá ◽  
Jorge L. S. Nunes ◽  
Carlos Lasso ◽  
Juan Posada ◽  
Ross Robertson ◽  
...  

We examined 308 specimens of the Indo-Pacific blenniid Omobranchus punctatus deposited in four museum collections, and analyzed data on their collection locations to assess its invasion on the Atlantic coast of Central and South America. This species occurs in shoreline estuarine and marine habitats in the Indo-West Pacific. Previous sampling and recent records in the Tropical West Atlantic from 1930 to 2004 produced 20 records for: Panamá, Colombia, Venezuela, Trinidad and Brazil. In this work, we provide data on 17 new records for the Gulfs of Venezuela and Paria in Venezuela, as well as four records for Maranhão and Pará states in NE Brazil. The temporal pattern of collections (1930 - 2009) and the proximity of most localities to ports and zones of ship traffic indicate that O. punctatus was initially introduced to the Atlantic by ships travelling from India to Trinidad. Within Brazil the introduction is linked to shipping connected to petroleum platforms. In Maranhão and Pará the introduction may have occurred as a result of fish sheltering in fouling on hulls of ships moving between ports around the mouth of the Amazon River. Alternatively, the spread of this species along of the American coast may reflect the expansion of the range of O. puntactus through larval dispersal in northward flowing currents. We recommend monitoring of this introduced species, and studies of its ecology in West Atlantic areas.


2016 ◽  
Vol 94 (3) ◽  
pp. 441 ◽  
Author(s):  
Carolina A. León ◽  
Gisela Oliván-Martínez ◽  
Gisela Oliván-Martínez ◽  
Juan Larraín ◽  
Juan Larraín ◽  
...  

2021 ◽  
Author(s):  
John Lindo ◽  
Andre Luiz Campelo dos Santos ◽  
Michael DeGiorgio ◽  
Gonzalo Figueiro

The prehistory of the people of Uruguay is greatly complicated by the dramatic and severe effects of European contact, as with most of the Americas. After the series of military campaigns that exterminated the last remnants of nomadic peoples, Uruguayan official history masked and diluted the former indigenous ethnic diversity into the narrative of a singular people that all but died out. Here we present the first whole genome sequences of the Indigenous people of the region before the arrival of Europeans, from an archaeological site in eastern Uruguay that dates from 2,000 years before present. We find a surprising connection to ancient individuals from Panama and eastern Brazil, but not to modern Amazonians. This result may be indicative of a distinct migration route into South America that may have occurred along the Atlantic coast. We also find a distinct ancestry previously undetected in South America. Though this work begins to piece together some of the demographic nuance of the region, the sequencing of ancient individuals from across Uruguay is needed to better understand the ancient prehistory and genetic diversity that existed before European contact, thereby helping to rebuild the history of the indigenous population of what is now Uruguay.


Climate ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 42 ◽  
Author(s):  
Diana Sousa-Guedes ◽  
Salvador Arenas-Castro ◽  
Neftalí Sillero

How species are distributed on Earth depends largely on climate factors. Whenever these environmental conditions change, species tend to shift their distributions to reach more favourable conditions. Distinct sets of species similarly distributed (i.e., chorotypes) occur in biogeographical regions with homogeneous environmental conditions. Here, we analysed whether biogeographical regions are unstable over time (from the past to the future). We modelled the realised niche of amphibians and reptiles in the Iberian Peninsula in the present, and several past and future climate scenarios. Then, we used Jaccard’s index and the unweighted pair group method (UPGMA) to define the biogeographical regions. Our results suggest that the biogeographical regions of Iberian amphibians and reptiles changed greatly over time, due to the climatic changes between periods. Biogeographical regions composed of species with Atlantic affinities changed particularly, overall gaining suitable areas in past colder periods and losing suitable areas in warmer periods. The areas of refugia for amphibians over time corresponded to the most humid regions (north-west of the peninsula), while the most important areas for reptiles occur in the south and on the Atlantic coast. The identification of biogeographical patterns considering past climate changes is essential to better apply conservation measures.


Sign in / Sign up

Export Citation Format

Share Document