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Angel Guerra - One of the best experts on this subject based on the ideXlab platform.
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allozyme divergence supporting the taxonomic separation of octopus Mimus and octopus maya from octopus vulgaris cephalopoda octopoda
Bulletin of Marine Science, 2002Co-Authors: Marcos Perezlosada, Angel Guerra, Andres SanjuanAbstract:Taxonomic status and phylogeny of shallow-water octopuses remain to be resolved. Recently the octopod inhabiting Peru and North Chilean waters has been identified on morphological basis as Octopus Mimus instead of O. vulgaris. The former shows faint paired ocelli whereas the latter is a non-ocellated species. Another ocellated octopus is O. maya, which is restricted to the Gulf of Mexico. Thirty allozyme loci were studied in O. Mimus collected from Peru, O. vulgaris from Spain and O. maya from the Gulf of Mexico, and in two other Spanish octopods (Eledone cirrhosa and E. moschata) which were used as outgroups. Genetic identity values (Nei, 1972) between O. vulgaris and O. minus-O. maya (mean I = 0.18) were typical of confamilial genera, whereas genetic identity between the two latter species (I = 0.44) was typical of congeneric species. Moreover, neighbor-joining and parsimony trees showed that O. Mimus and O. maya constitute a monophyletic clade. These genetic results suggest that O. mimes and O. maya should be considered as belonging to a different confamilial genus than O. vulgaris, and support the hypothesis of both taxa as Panamanian geminate species resulting from an allopatric speciation event associated with the uplift of Central America.
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Growth of Octopus Mimus (Cephalopoda, Octopodidae) in wild populations
Fisheries Research, 1999Co-Authors: Tito Cortez, Ángel F. González, Angel GuerraAbstract:Abstract A total of 6171 specimens of Octopus Mimus was collected from the commercial small-scale fishery in northern Chilean waters (off Iquique) between January 1991 and March 1992. The animals were grouped by sex, size and month for modal progression analysis (MPA). Total length of the animals ranged from 24 (66 g) to 107 cm (4358 g) for males and from 28 (63 g) to 115 cm (3714 g) for females. There were no significant differences in the length–weight relationship between sexes except in summer. The size structure of the exploited population of O. Mimus is rather complex and MPA indicated six sub-annual cohorts for males and five for females. Instantaneous relative growth rate ( G ) in total body weight varied from 0.29% to 1.37% d −1 and from 0.23% to 1.78% d −1 for males and females, respectively. Seasonality and water temperature affected G in both sexes. Differences in G among sub-annual cohorts within the same season were found and it was observed that G tended to decrease with size.
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Growth of cultured Octopus Mimus (Cephalopoda, Octopodidae)
Fisheries Research, 1999Co-Authors: Tito Cortez, Ángel F. González, Angel GuerraAbstract:Abstract Laboratory rearing of 19 Octopus Mimus from 40 to 589 g at 20.1±1.8°C (September to December 1991) provided information on the growth pattern and variation in instantaneous relative growth rate ( G ) of this Chilean littoral octopus. The three smallest specimens (ranging from 40 to 49.8 g) attained an average weight of 558 g in 70 days. Growth of this species had two phases. Growth was exponential during the first 40 days of culture with an average G of 5.33%. It slowed and became logarithmic when the animals attained weights ranging from 326.6 to 439 g. Instantaneous relative growth rate decreased from 2.25% to 0.99% during the logarithmic phase. A similar pattern was found for the 16 larger specimens (61.4–406.4 g initial weight). The change in growth pattern observed between the exponential and logarithmic phases occurred at body weights ranging from 326.6 to 454.2 g. No differences in growth were found between sexes in O. Mimus . The growth pattern of this species is discussed and compared to other small-egged octopus species raised in captivity.
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Growth of Octopus Mimus (Cephalopoda, Octopodidae) in wild populations
Fisheries Research, 1999Co-Authors: Tito Cortez, Ángel F. González, Angel GuerraAbstract:9 páginas, 4 figuras, 3 tablasA total of 6171 specimens of Octopus Mimus was collected from the commercial small-scale fishery in northern Chilean waters (off Iquique) between January 1991 and March 1992. The animals were grouped by sex, size and month for modal progression analysis (MPA). Total length of the animals ranged from 24 (66 g) to 107 cm (4358 g) for males and from 28 (63 g) to 115 cm (3714 g) for females. There were no significant differences in the length–weight relationship between sexes except in summer. The size structure of the exploited population of O. Mimus is rather complex and MPA indicated six sub-annual cohorts for males and five for females. Instantaneous relative growth rate (G) in total body weight varied from 0.29% to 1.37% d−1 and from 0.23% to 1.78% d−1 for males and females, respectively. Seasonality and water temperature affected G in both sexes. Differences in G among sub-annual cohorts within the same season were found and it was observed that G tended to decrease with sizePeer reviewe
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drilling behaviour of octopus Mimus gould
Journal of Experimental Marine Biology and Ecology, 1998Co-Authors: Tito Cortez, Bernardino G Castro, Angel GuerraAbstract:Abstract The hole-drilling behaviour of the common octopus in North Chilean waters, Octopus Mimus , on nine of its molluscan prey was studied in 70 specimens of 10–2000 g body weight in the laboratory. The occurrence of perforation was low, only 24.50% of the ingested prey were drilled. The bivalve Protothaca thaca (Molina) was the prey most frequently perforated, on 73.30% of occasions. The mean length of the P. thaca ingested increased significantly with octopus weight ( r 2 =0.982, p p Concholepas concholepas (Brugiere). The most specific location occurred when Protothaca thaca was perforated; 83% of the holes were located within or close to the myostracum of the anterior, mainly, and posterior adductor muscles of the clam. Within these small areas, there was a preference for the proximal edges.
Tito Cortez - One of the best experts on this subject based on the ideXlab platform.
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Growth of Octopus Mimus (Cephalopoda, Octopodidae) in wild populations
Fisheries Research, 1999Co-Authors: Tito Cortez, Ángel F. González, Angel GuerraAbstract:Abstract A total of 6171 specimens of Octopus Mimus was collected from the commercial small-scale fishery in northern Chilean waters (off Iquique) between January 1991 and March 1992. The animals were grouped by sex, size and month for modal progression analysis (MPA). Total length of the animals ranged from 24 (66 g) to 107 cm (4358 g) for males and from 28 (63 g) to 115 cm (3714 g) for females. There were no significant differences in the length–weight relationship between sexes except in summer. The size structure of the exploited population of O. Mimus is rather complex and MPA indicated six sub-annual cohorts for males and five for females. Instantaneous relative growth rate ( G ) in total body weight varied from 0.29% to 1.37% d −1 and from 0.23% to 1.78% d −1 for males and females, respectively. Seasonality and water temperature affected G in both sexes. Differences in G among sub-annual cohorts within the same season were found and it was observed that G tended to decrease with size.
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Growth of cultured Octopus Mimus (Cephalopoda, Octopodidae)
Fisheries Research, 1999Co-Authors: Tito Cortez, Ángel F. González, Angel GuerraAbstract:Abstract Laboratory rearing of 19 Octopus Mimus from 40 to 589 g at 20.1±1.8°C (September to December 1991) provided information on the growth pattern and variation in instantaneous relative growth rate ( G ) of this Chilean littoral octopus. The three smallest specimens (ranging from 40 to 49.8 g) attained an average weight of 558 g in 70 days. Growth of this species had two phases. Growth was exponential during the first 40 days of culture with an average G of 5.33%. It slowed and became logarithmic when the animals attained weights ranging from 326.6 to 439 g. Instantaneous relative growth rate decreased from 2.25% to 0.99% during the logarithmic phase. A similar pattern was found for the 16 larger specimens (61.4–406.4 g initial weight). The change in growth pattern observed between the exponential and logarithmic phases occurred at body weights ranging from 326.6 to 454.2 g. No differences in growth were found between sexes in O. Mimus . The growth pattern of this species is discussed and compared to other small-egged octopus species raised in captivity.
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Growth of Octopus Mimus (Cephalopoda, Octopodidae) in wild populations
Fisheries Research, 1999Co-Authors: Tito Cortez, Ángel F. González, Angel GuerraAbstract:9 páginas, 4 figuras, 3 tablasA total of 6171 specimens of Octopus Mimus was collected from the commercial small-scale fishery in northern Chilean waters (off Iquique) between January 1991 and March 1992. The animals were grouped by sex, size and month for modal progression analysis (MPA). Total length of the animals ranged from 24 (66 g) to 107 cm (4358 g) for males and from 28 (63 g) to 115 cm (3714 g) for females. There were no significant differences in the length–weight relationship between sexes except in summer. The size structure of the exploited population of O. Mimus is rather complex and MPA indicated six sub-annual cohorts for males and five for females. Instantaneous relative growth rate (G) in total body weight varied from 0.29% to 1.37% d−1 and from 0.23% to 1.78% d−1 for males and females, respectively. Seasonality and water temperature affected G in both sexes. Differences in G among sub-annual cohorts within the same season were found and it was observed that G tended to decrease with sizePeer reviewe
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drilling behaviour of octopus Mimus gould
Journal of Experimental Marine Biology and Ecology, 1998Co-Authors: Tito Cortez, Bernardino G Castro, Angel GuerraAbstract:Abstract The hole-drilling behaviour of the common octopus in North Chilean waters, Octopus Mimus , on nine of its molluscan prey was studied in 70 specimens of 10–2000 g body weight in the laboratory. The occurrence of perforation was low, only 24.50% of the ingested prey were drilled. The bivalve Protothaca thaca (Molina) was the prey most frequently perforated, on 73.30% of occasions. The mean length of the P. thaca ingested increased significantly with octopus weight ( r 2 =0.982, p p Concholepas concholepas (Brugiere). The most specific location occurred when Protothaca thaca was perforated; 83% of the holes were located within or close to the myostracum of the anterior, mainly, and posterior adductor muscles of the clam. Within these small areas, there was a preference for the proximal edges.
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Reproduction and condition of female Octopus Mimus (Mollusca: Cephalopoda)
Marine Biology, 1995Co-Authors: Tito Cortez, Bernardino G Castro, Angel GuerraAbstract:The relationship between reproduction and condition was studied in a 15 mo sample of 919 maturing, mature and post-spawning female Octopus Mimus (388 to 3714 g) caught in Iquique (North Chile). O. Mimus is a semelparous species, with reproduction taking place all year round. Investment in reproductive tissues was, on average, 9.9% of mature female body weight, independent of season. However, somatic growth during maturation was dependent on season and varied between 26 and 63% of the whole-body growth in weight. The condition of females did not vary markedly until spawning, although seasonal variations were apparent, winter being the most unfavourable. Condition deteriorated dramatically after spawning, during parental care of the eggs. During this period, somatic-tissue depletion, mainly from the muscles, was >25% of the total body weight of mature females. The fecundity of O. Mimus was probably limited by the costs associated with parental care of the eggs.
Ángel F. González - One of the best experts on this subject based on the ideXlab platform.
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Growth of Octopus Mimus (Cephalopoda, Octopodidae) in wild populations
Fisheries Research, 1999Co-Authors: Tito Cortez, Ángel F. González, Angel GuerraAbstract:Abstract A total of 6171 specimens of Octopus Mimus was collected from the commercial small-scale fishery in northern Chilean waters (off Iquique) between January 1991 and March 1992. The animals were grouped by sex, size and month for modal progression analysis (MPA). Total length of the animals ranged from 24 (66 g) to 107 cm (4358 g) for males and from 28 (63 g) to 115 cm (3714 g) for females. There were no significant differences in the length–weight relationship between sexes except in summer. The size structure of the exploited population of O. Mimus is rather complex and MPA indicated six sub-annual cohorts for males and five for females. Instantaneous relative growth rate ( G ) in total body weight varied from 0.29% to 1.37% d −1 and from 0.23% to 1.78% d −1 for males and females, respectively. Seasonality and water temperature affected G in both sexes. Differences in G among sub-annual cohorts within the same season were found and it was observed that G tended to decrease with size.
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Growth of cultured Octopus Mimus (Cephalopoda, Octopodidae)
Fisheries Research, 1999Co-Authors: Tito Cortez, Ángel F. González, Angel GuerraAbstract:Abstract Laboratory rearing of 19 Octopus Mimus from 40 to 589 g at 20.1±1.8°C (September to December 1991) provided information on the growth pattern and variation in instantaneous relative growth rate ( G ) of this Chilean littoral octopus. The three smallest specimens (ranging from 40 to 49.8 g) attained an average weight of 558 g in 70 days. Growth of this species had two phases. Growth was exponential during the first 40 days of culture with an average G of 5.33%. It slowed and became logarithmic when the animals attained weights ranging from 326.6 to 439 g. Instantaneous relative growth rate decreased from 2.25% to 0.99% during the logarithmic phase. A similar pattern was found for the 16 larger specimens (61.4–406.4 g initial weight). The change in growth pattern observed between the exponential and logarithmic phases occurred at body weights ranging from 326.6 to 454.2 g. No differences in growth were found between sexes in O. Mimus . The growth pattern of this species is discussed and compared to other small-egged octopus species raised in captivity.
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Growth of Octopus Mimus (Cephalopoda, Octopodidae) in wild populations
Fisheries Research, 1999Co-Authors: Tito Cortez, Ángel F. González, Angel GuerraAbstract:9 páginas, 4 figuras, 3 tablasA total of 6171 specimens of Octopus Mimus was collected from the commercial small-scale fishery in northern Chilean waters (off Iquique) between January 1991 and March 1992. The animals were grouped by sex, size and month for modal progression analysis (MPA). Total length of the animals ranged from 24 (66 g) to 107 cm (4358 g) for males and from 28 (63 g) to 115 cm (3714 g) for females. There were no significant differences in the length–weight relationship between sexes except in summer. The size structure of the exploited population of O. Mimus is rather complex and MPA indicated six sub-annual cohorts for males and five for females. Instantaneous relative growth rate (G) in total body weight varied from 0.29% to 1.37% d−1 and from 0.23% to 1.78% d−1 for males and females, respectively. Seasonality and water temperature affected G in both sexes. Differences in G among sub-annual cohorts within the same season were found and it was observed that G tended to decrease with sizePeer reviewe
Lukas F. Keller - One of the best experts on this subject based on the ideXlab platform.
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Microsatellite primers for the four Galápagos mockingbird species (Mimus parvulus, Mimus macdonaldi, Mimus melanotis and Mimus trifasciatus).
Molecular ecology resources, 2009Co-Authors: Paquita E. A. Hoeck, Thomas Bucher, Peter Wandeler, Lukas F. KellerAbstract:Nineteen di- and tetranucleotide and one trinucleotide microsatellite DNA markers were isolated from the Galapagos mockingbird (Mimus parvulus) and tested for cross-species amplification in the other three mockingbird species in the Galapagos. In addition, primers for two microsatellite loci previously developed for Mimus polyglottos were redesigned to obtain shorter amplification fragments. The number of alleles per locus and species ranged from 1 to 8, and expected heterozygosity varied from 0.0 to 0.809. These microsatellite markers will be useful to study levels of inbreeding in different island populations.
Irene De Los Angeles Barrigasosa - One of the best experts on this subject based on the ideXlab platform.
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genetic structure of octopus Mimus gould 1852 along three biogeographic marine provinces
Marine Biodiversity, 2020Co-Authors: Ricardo Pliegocardenas, Unai Markaida, Scarlett M. Prieto, Marco A. Apon, Irene De Los Angeles BarrigasosaAbstract:The population genetic structure of a species is frequently shaped by biogeographic barriers that prevent the movement of individuals from one genetic population to another. Although Octopus Mimus Gould, 1852 was reported to inhabit the shallow marine waters of the Peruvian province, recent studies suggest its synonymy with O. hubbsorum Berry, 1953 from the Panamanian and the Cortez provinces where it is the main octopus species caught in the artisanal fishery. The aim of the present study was to assess the genetic variability of O. Mimus and to determine the presence of population structure across three sampled regions of the eastern Pacific Ocean using the mitochondrial marker cytochrome c oxidase subunit I. The hypothesis that the biogeographic boundary between the Panamanian and Peruvian provinces acts as a genetic break was further tested and recognized by the conformation of two phylogenetic clades and two haplogroups. Results indicate that these lineages are demographically independent populations of O. Mimus and do not represent different species as evidenced by the Generalized Mixed Yule Coalescent method. The oceanographic processes have apparently allowed enough genetic flow along the Pacific coast yielding low but significant levels of genetic structure (FST = 0.16, p < 0.05) as seen in some fish populations.
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the complete mitochondrial genomes of two octopods of the eastern pacific ocean octopus Mimus and octopus fitchi cephalopoda octopodidae and their phylogenetic position within octopoda
Molecular Biology Reports, 2020Co-Authors: Erika Magallongayon, Miguel Angel Del Rioportilla, Irene De Los Angeles BarrigasosaAbstract:The complete mitochondrial genomes of two important octopus species from the eastern Pacific were sequenced, obtaining their complete nucleotide sequences. Octopus Mimus is the most important commercially catched species along the eastern Pacific, from Mexico to Chile, whereas ‘Octopus’ fitchi is a pigmy species with uncertain taxonomic genus. The mitogenomes of Octopus Mimus and ‘Octopus’ fitchi were 15,696 and 15,780 base pairs (bp) in length with an A + T composition of 75.5% and 75.8%, respectively. Each genome contains 13 protein-coding genes, 22 tRNA genes, and two rRNA genes, as well as a control region. Gene order is maintained as reported for other species of the Octopodidae. The phylogenetic analysis based on the concatenated thirteen protein-coding genes confirms that O. Mimus belongs to the genus Octopus, which is supported by the genetic distance (11–16%) whereas the position of ‘O’. fitchi within this group it is not supported. The analysis also indicated that the phylogenetic position of ‘O’. fitchi is closer to Callistoctopus than to the Cistopus or the Amphioctopus clades. Based on the tree topology and the high genetic distance observed (24–25%), we suggest that ‘O’. fitchi might represent a different genus.