Sergio Cházaro-Olvera

Lista actualizada de las especies de anfípodos (Peracarida: Gammaridea y Corophiidea) marinos invasores en México

An updated checklist of the marine invasive amphipod species from Mexico is documented. This list includes 11 species, belonging to the suborders Gammaridea and Corophiidea, and grouped in five families and six genera. Information about distribution, habitat, natural history, and dispersal mechanisms was added, according to the Sistema Nacional de Informacion sobre Biodiversidad and Analisis de Riesgo. The species Ampelisca abdita, A.burkei, A. schellenbergi, Melita nitida, Colomastix irciniae, C. tridentata, Ampithoe longimana, A. pollex, Apocorophium acutum, Monocorophium acherusicum, and M. insidiosum, were characterized as marine invasive species from Mexico.

Cadmium, copper and lead in macroalgae from the Veracruz Reef System, Gulf of Mexico: Spatial distribution and rainy season variability

This study focused on the spatial distribution of trace metals in the Veracruz Reef System in the Southern Gulf of Mexico, and its variability in the early (July) and late (September) rainy season of 2008, by analyzing the concentration of Cd, Cu and Pb in benthic macroalgae. Mean concentrations are lower (Pb 295 ± 347 ng g(-1), Cd 17.9 ± 15.0 ng g(-1)), or similar (Cu 3.4 ± 4.5 μg g(-1)) to those reported from other coastal areas. Cd and Pb concentrations are influenced by the discharge of the Jamapa River, evidencing a fluvial control on coastal trace metal levels. Also, Cd and Cu concentrations were lower in the late rainy season, when there is a high load of suspended sediments derived from fluvial discharge, which probably adsorb dissolved metals decreasing their bioavailability. Pb concentrations have been decreasing in the last two decades in the SGM, after the banning of leaded-gasoline in the late 20th century.

Growth, Mortality, and Fecundity of Palaemonetes pugio from a Lagoon System Inlet in the Southwestern Gulf of Mexico

Abstract The objective of the current study is to understand population characteristics of the grass shrimp Palaemonetes pugio by describing growth, population structure, mortality, fecundity, and size at sexual maturity from a lagoon system inlet in the southwestern Gulf of Mexico. The shrimps were collected between January and December 2007 by otter trawl of 1-mm mesh size; salinity and water temperature were recorded simultaneously. Regressions were applied between total length (TL) and total weight (TW) of females and males. Growth parameters were estimated by length-frequency distributions with 0.01-mm length interval of carapace using the von Bertalanffy growth function (VBGF), mortality was calculated with an exponential model. To represent fecundity, the potential model was selected. The average salinity and temperature values were 6.39 ± 2.49 ppt and 27.63 ± 1.59°C, respectively. The number of females was higher than for males in winter and spring, suggesting a reproductive strategy that increases the probability for the male of finding a receptive female. The K (Bertalanffy growth coefficient) values were 0.48 for males and 0.43 for females. This could indicate a reduction of female energy investment in growth, directing it rather to reproduction. The instantaneous mortality estimates (Z) suggest a relationship with the reproductive period; the highest mortality was encountered from April to September. Female size at sexual maturity was estimated to be 2.41 cm TL, showing that ovarian development starts in winter and continues until early spring. Consequently, P. pugio showed faster growth, a seasonally oscillating growth pattern, a rather short life span, a somewhat high mortality, and an early onset of sexual maturity, which is considered to be similar to r selected species.

Morphological differentiation of megalopae in the family Panopeidae Ortmann, 1893, from a lagoon system inlet in the southwestern Gulf of Mexico

Some morphological differences among the megalopae of the family Panopeidae have been determined. The megalopa stage was obtained from the artificial inlet of the Camaronera Lagoon, Veracruz, Mexico. Morphological analysis consisted of: dissection of the antennule, carapace, and telson, classification and counting of setae and aesthetascs, and measurements of carapace width and carapace length. A total of 96 172 megalopae of several species of Brachyura were obtained, of which 577 belonged to the family Panopeidae. Six species of this family were identified: Panopeus herbstii, P. lacustris, Dyspanopeus texanus, Neopanope packardii, Eurypanopeus depressus, and Hexapanopeus angustifrons. Morphological differences include: E. depressus lacks anterolateral projections and was smallest in size; D. texanus has two subterminal setae and four terminal setae on the endopod of the antennula; N. packardii has six strong plumose setae on the second segment of the uropod; H. angustifrons has one subterminal seta and two terminal setae on the endopod of the antennula. With respect to carapace size, the two species of the genus Panopeus, P. herbstii and P. lacustris, present the largest carapace size, while the smallest size was registered for E. depressus. A key for the identification of these megalopae of the family Panopeidae is presented. Se determinaron algunas diferencias morfologicas en megalopas de la familia Panopeidae. Las megalopas se obtuvieron en la boca artificial de la Laguna de Camaronera, Veracruz, Mexico. El analisis morfologico consistio en: la diseccion de la antenula, del caparazon, y del telson, la clasificacion y conteo de las setas y estetes, y la medicion del ancho y largo del caparazon. Se obtuvieron un total de 96 172 megalopas de varias especies de Brachyura, de las cuales 577 pertenecieron a la familia Panopeidae. Se identificaron seis especies de esta familia: Panopeus herbstii, P. lacustris, Dyspanopeus texanus, Neopanope packardii, Eurypanopeus depressus y Hexapanopeus angustifrons. Las diferencias morfologicas mostraron que E. depressus carece las proyecciones anterolaterales en el caparazon y es mas pequeno; D. texanus tiene dos setas subterminales y cuatro setas terminales en el endopodo del antenula; N. packardii tiene seis fuertes setas plumosas en el segundo segmento del uropodo; H. angustifrons tiene un seta subterminal y dos setas terminales en el endopodo de la antenula. Con respecto al tamano de caparazon, la dos especies del genero Panopeus: P. herbstii y P. lacustris, presentaron el tamano mas grande del caparazon, mientras que el tamano mas pequeno se registro para E. depressus. Se presenta una clave de identificacion para las megalopas de estas especies de la familia Panopeidae.

Growth of individuals within the parasite-host association Bopyrina abbreviata (Isopoda, Bopyridae) and Hippolyte zostericola (Decapoda, Caridea), and variations in parasite morphology

Abstract Growth is an important ecological factor of species on which information is scant for host–parasite associations. A sample of 680 Hippolyte zostericola parasitized by the isopod Bopyrina abbreviata were collected at Términos Lagoon, Mexico, to evaluate the growth of both members of this association by the von Bertalanffy method, as well as longevity of parasitized and unparasitized hosts, and parasite females. Misidentification of bopyrid species could be attributed to morphological variations of stages of development, so the relative growth of some body parts of B. abbreviata females were estimated at different stages of development. Overall, H. zostericola parasitized by B. abbreviata had lower growth rate and longevity than did unparasitized shrimp. Unparasitized H. zostericola females lived longer (10.2 months) than males (8.9 months), but parasitized males lived longer (7.31 months) than females (5.62 months). B. abbreviata longevity (5.98 months) was similar to that estimated for its host (6.31 months). The relative growth of the morphological characters differed between immature and mature stages of B. abbreviata females; the appearance of coxal plates, tergal projections and the fusion of pleomeres was progressive throughout development, so a combination of characters is proposed to allow differentiation between immature and mature females of B. abbreviata.

Morphology of the Pachygrapsus gracilis (De Saussure, 1858) megalopa (Brachyura, Grapsidae) reared in the laboratory

[This study describes the morphology of the megalopa stage of Pachygrapsus gracilis in detail and compares it with that of other species collected in the Camaronera Lagoon inlet of the Alvarado Lagoon system, Veracruz, Mexico. The biological material was collected with a conical net (1.0 m length, 0.75 m width, 243 μm mesh opening). Rearing was conducted in a vertical re-circulating system. We find that the numbers and types of setae to differentiate the megalopa of P. gracilis are on the following structures: antennula, basal and coxal endite of the maxillule, basal endite and scaphognathite of the maxilla, protopodite and epipodite of the first maxilliped, fifth segment of the endopod of the second maxilliped, fourth and fifth segment of the endopod and the epipodite of the third maxilliped, and the number of setae of the pleopods. The P. gracilis megalopa has the largest-sized carapace of all the megalopae of the crab species of the Camaronera lagoon inlet. En este estudio se realizo la descripcion morfologica de la megalopa de Pachygrapsus gracilis y se comparo con otras especies colectadas en la boca de la laguna Camaronera del Sistema Lagunar de Alvarado, Veracruz, Mexico. El material biologico fue colectado con una red conica (1.0 m de longitud, 0.75 m de ancho y 243 μm de abertura de malla). El cultivo se realizo en un sistema de re-circulacion vertical. Nosotros encontramos que el numero y tipo de setas para diferenciar a la megalopa de P. gracilis estan sobre las siguientes estructuras: antenula, endito basal y endito coxal de la maxilula, endito basal y escafognatito de la maxila, protopodito y epipodito del primer maxilipedo, quinto segmento del endopodo del segundo maxilipedo, cuarto y quinto segmento del endopodo y el epipodito del tercer maxilipedo y el numero de setas de los pleopodos. P. gracilis presento la talla mas grande respecto a otras especies colectadas en la boca de la laguna Camaronera., This study describes the morphology of the megalopa stage of Pachygrapsus gracilis in detail and compares it with that of other species collected in the Camaronera Lagoon inlet of the Alvarado Lagoon system, Veracruz, Mexico. The biological material was collected with a conical net (1.0 m length, 0.75 m width, 243 μm mesh opening). Rearing was conducted in a vertical re-circulating system. We find that the numbers and types of setae to differentiate the megalopa of P. gracilis are on the following structures: antennula, basal and coxal endite of the maxillule, basal endite and scaphognathite of the maxilla, protopodite and epipodite of the first maxilliped, fifth segment of the endopod of the second maxilliped, fourth and fifth segment of the endopod and the epipodite of the third maxilliped, and the number of setae of the pleopods. The P. gracilis megalopa has the largest-sized carapace of all the megalopae of the crab species of the Camaronera lagoon inlet. En este estudio se realizo la descripcion morfologica de la megalopa de Pachygrapsus gracilis y se comparo con otras especies colectadas en la boca de la laguna Camaronera del Sistema Lagunar de Alvarado, Veracruz, Mexico. El material biologico fue colectado con una red conica (1.0 m de longitud, 0.75 m de ancho y 243 μm de abertura de malla). El cultivo se realizo en un sistema de re-circulacion vertical. Nosotros encontramos que el numero y tipo de setas para diferenciar a la megalopa de P. gracilis estan sobre las siguientes estructuras: antenula, endito basal y endito coxal de la maxilula, endito basal y escafognatito de la maxila, protopodito y epipodito del primer maxilipedo, quinto segmento del endopodo del segundo maxilipedo, cuarto y quinto segmento del endopodo y el epipodito del tercer maxilipedo y el numero de setas de los pleopodos. P. gracilis presento la talla mas grande respecto a otras especies colectadas en la boca de la laguna Camaronera.]

A new species of cirolanid isopod (Peracarida, Isopoda) collected from Cenote Aerolito, Cozumel Island, northwestern Caribbean

A new species of Cirolana Leach, 1818, collected from Cenote Aerolito, Cozumel Island, Mexican Caribbean, is described. Cirolana (Anopsilana) adriani sp. nov. has a body 2.7× as long as wide, widest at pereonites 5-6; cephalon smooth, with small rostral point; pereonites without tubercles or ridges; antenna 2 not surpassing back of segment 2 of pereon; pleonite 4 lacking free ventrolateral margins; pleotelson as long as wide, smooth, with 9 distal robust setae; appendix masculina extremely long, 2× as long as endopod of pleopod 2. The main differences between the new species and the marine species Cirolana (Anopsilana) jonesi (Kensley, 1987) and C. (A.) sinu (Kensley & Schotte, 1994), as well as the stygobitic species C. (A.) yucatana Botosaneanu & Iliffe, 2000, the most similar known species of Cirolana (Anopsilana) in the region, are described. This is the second isopod of the genus Cirolana recorded from the karstic systems of the Yucatan Peninsula.

TRANSPORT OF FARFANTEPENAEUS AZTECUS POSTLARVAE IN THREE LAGOON-SYSTEM INLETS IN THE SOUTHWESTERN GULF OF MEXICO

[This study evaluates the night-time recruitment of Farfantepenaeus aztecus postlarvae and its relation with temperature, salinity, and velocity and flow direction of the current in the artificial inlet of the Camaronera lagoon of Alvarado, Veracruz, the Soto la Marina river inlet of Tamaulipas, and the Puerto Real inlet of Terminos lagoon, Campeche. Sampling was done during the night. A conical 243 μm mesh net was used for capture. The total catch of F. aztecus for the three coastal systems was 95,279 postlarvae. The average temperature was 28.23 ± 1.37°C, salinity 23.54 ± 7.10 psu, and stream velocity 0.39 ± 0.18 m s–1. During this study, the existence of recruitment peaks between 20:00 h and 02:00 h was established. The correlation coefficient between the density of postlarvae in the hours of sampling and environmental factors was significant (P 23 psu. Recruitment is related to the influx of seawater towards the coastal systems. There was no significant difference in postlarval density (P > 0.05) between consecutive sampling cycles. En este estudio se evaluo el reclutamiento de las postlarvas de Farfantepenaeus aztecus y su relacion con la temperatura, salinidad, velocidad y direccion de la corriente en la boca de comunicacion artificial de la laguna Camaronera de Alvarado, Veracruz, la boca del rio Soto la Marina, Tamaulipas y la boca de comunicacion Puerto Real de la laguna de Terminos, Campeche. Los muestreos se realizaron durante la noche. Para las capturas se utilizo una red conica de 243 micras de abertura de malla. La abundancia total de F. aztecus para los tres sistemas fue de 95 279 postlarvas. El promedio de temperatura fue de 28,23 ± 1,37°C, salinidad de 23,54 ± 7,10 ups y velocidad de corriente de 0,39 ± 0,18 m s–1. Durante la realizacion de este estudio se presentaron los picos de reclutamiento entre las 20:00 h y las 02:00. El coeficiente de correlacion entre la densidad de postlarvas y los factores ambientales fue significativo (P 0,05) entre los ciclos de muestreo consecutivos., This study evaluates the night-time recruitment of Farfantepenaeus aztecus postlarvae and its relation with temperature, salinity, and velocity and flow direction of the current in the artificial inlet of the Camaronera lagoon of Alvarado, Veracruz, the Soto la Marina river inlet of Tamaulipas, and the Puerto Real inlet of Terminos lagoon, Campeche. Sampling was done during the night. A conical 243 μm mesh net was used for capture. The total catch of F. aztecus for the three coastal systems was 95,279 postlarvae. The average temperature was 28.23 ± 1.37°C, salinity 23.54 ± 7.10 psu, and stream velocity 0.39 ± 0.18 m s–1. During this study, the existence of recruitment peaks between 20:00 h and 02:00 h was established. The correlation coefficient between the density of postlarvae in the hours of sampling and environmental factors was significant (P 23 psu. Recruitment is related to the influx of seawater towards the coastal systems. There was no significant difference in postlarval density (P > 0.05) between consecutive sampling cycles. En este estudio se evaluo el reclutamiento de las postlarvas de Farfantepenaeus aztecus y su relacion con la temperatura, salinidad, velocidad y direccion de la corriente en la boca de comunicacion artificial de la laguna Camaronera de Alvarado, Veracruz, la boca del rio Soto la Marina, Tamaulipas y la boca de comunicacion Puerto Real de la laguna de Terminos, Campeche. Los muestreos se realizaron durante la noche. Para las capturas se utilizo una red conica de 243 micras de abertura de malla. La abundancia total de F. aztecus para los tres sistemas fue de 95 279 postlarvas. El promedio de temperatura fue de 28,23 ± 1,37°C, salinidad de 23,54 ± 7,10 ups y velocidad de corriente de 0,39 ± 0,18 m s–1. Durante la realizacion de este estudio se presentaron los picos de reclutamiento entre las 20:00 h y las 02:00. El coeficiente de correlacion entre la densidad de postlarvas y los factores ambientales fue significativo (P 0,05) entre los ciclos de muestreo consecutivos.]

Rearing of juvenile dark crabs, Callinectes rathbunae contreras, 1930, under laboratory conditions

In the present study, we reared juvenile dark crabs, Callinectes rathbunae under laboratory conditions. We determined growth rate, increase in carapace width, moult consumption, regeneration of appendages, and survival. The crabs were collected in March 2004 from the Alvarado Lagoon System in the state of Veracruz, Mexico. Crabs were transported to the laboratory and acclimated to 5 and 15 psu and a temperature of 25 ± 1° C. Growth rate was determined by the difference in size at the time interval between the pre-moult and moult stages. Survival was assessed by counting the juvenile crabs during rearing, moult consumption was determined after 24 hours, and regeneration of appendages at the next moult. The size of juveniles ranged from 1.7 to 6.4 cm. Results revealed that carapace increase was greater at 15 psu, being 35.29% for the 1.7-2.8 cm size range. The mean growth rate at 5 psu was 0.33 ± 0.07 mm/day and 0.76 ± 0.12 mm/day at 15 psu. Moult consumption was 50%. A 100% regeneration of appendages was observed after moulting. Survival was best at 15 psu, with 78.31%. En el presente estudio se realizo el cultivo de cangrejos juveniles de Callinectes rathbunae en condiciones de laboratorio. Se determino la tasa de crecimiento, el incremento en el ancho del caparazon, el consumo de la muda, la regeneracion de apendices y la sobrevivencia. La colecta se realizo en Marzo de 2004 en el Sistema lagunar de Alvarado, Veracruz, Mexico. Los cangrejos fueron transportados al laboratorio y aclimatados a 5 y 15 ups y temperatura de 25 ± 1°C. La tasa de crecimiento se determino por la diferencia de talla y el intervalo de tiempo transcurrido entre la premuda y la postmuda, la sobrevivencia por el conteo de cangrejos juveniles durante el tiempo de cultivo, el consumo de la muda despues de 24 h y la regeneracion de los apendices a la siguiente muda. El intervalo de talla de los juveniles fue de 1,7 a 6,4 cm. Los resultados mostraron que el incremento en el ancho del caparazon fue mayor en una salinidad de 15 ups con el 35. 29% en el intervalo de talla de 1,7 a 2,8 cm. Las tasa de crecimiento promedio a 5 ups fue de 0,33 ± 0,07 mm/dia y a 15 ups fue de 0,76 ± 0,12 mm/ dia. El consumo de muda fue del 50%. Se observo un 100% de regeneracion de apendices despues de la muda. El porcentaje de sobrevivencia fue mayor a 15 ups con el 78,31%.

Fish discard by-catch shrimp trawl (rainy season 2013) in south central coast of Veracruz, Mexico

The brown shrimp (Penaeus aztecus) fishery is the most important in the Gulf of Mexico. This fishery takes non-target species or by-catch fauna, mainly teleost fishes, which are incidentally captured. Some of the by-catch species has commercial use and the rest of them are discarded. Therefore, it is important to describe the composition of the discarded fauna, to determine the impacts under the ecosystem approach. Discarding catch of shrimp trawls carried out in 2013 on the continental shelf off the State of Veracruz in different depth intervals (22-46 and > 46 m) was analyzed. For each trawl, the shrimp catch, the commercial by-catch and the discarding were recorded and the catch ratios respect to shrimp, were obtained. A discard sample was taken and the species were identified, the total length was taken and the ecological parameters were calculated. The non-parametric multiple dimensional scaling test was performed. A total of 7,178 fishes were collected from 34 families, 46 genera and 51 species. The ratio of commercial species by-catch: shrimp and discard: shrimp was 15.41:1 and 40:1 kg, respectively. The species with high relative dominance were Citharichthys macrops, Synodus foetens, Diplectrum bivittatum, Rhomboplites aurorubens and Upeneus parvus. The species with greater importance index were C. macrops, S. foetens, and D. bivittatum. The 43.14% of the discarded species are used as food and 7.84% as bait. The maximum diversity (H ́) was 3.76 bits ind-1 and the trophic level was 4.31. The study of discard composition is a basis to assess the impact generated by the shrimp trawlers and provides guidelines for identify changes in the community structure.espanolLa pesqueria del camaron cafe Penaeus aztecus es la mas importante en el Golfo de Mexico. En esta pesqueria se capturan de manera incidental especies no objetivo compuestas mayormente por peces teleosteos. Es importante describir la composicion del descarte, para determinar el impacto de los arrastres camaroneros bajo un enfoque ecosistemico. Se analizo la captura de descarte de arrastres camaroneros realizados en 2013 en la plataforma continental del Estado de Veracruz en 22-46 y >46 m de profundidad. Para cada arrastre se registro la captura de camaron, fauna de acompanamiento comercial, descarte y fauna de acompanamiento. Se tomo una muestra del descarte, se identificaron las especies y se calcularon los parametros ecologicos de la muestra. Se realizo una prueba de escalamiento dimensional multiple no parametrica. De 87 lances de pesca, se analizaron 7.178 organismos correspondientes a 34 familias, 46 generos y 51 especies. Las especies con mayor dominancia relativa y mayor valor del indice de importancia fueron: Citharichthys macrops, Synodus foetens, Diplectrum bivittatum, Rhomboplites aurorubens y Upeneus parvus. Un alto porcentaje de las especies de descarte (43,14%) presentan uso potencial de alimento y 7,84% carnada. En promedio, la relacion Fauna de Acompanamiento Comercial:Camaron y Descarte:Camaron fue de 15,41:1 y 40:1 kg, respectivamente. El valor maximo de diversidad (H´) fue de 3,76 bits ind-1 y el Nivel Trofico de 4,31. El estudio de la composicion de los descartes es base para evaluar el impacto generado por los arrastres de camaron en la costa veracruzana y proporciona pautas para identificar cambios en la estructura de la comunidad. EnglishThe brown shrimp (Penaeus aztecus) fishery is the most important in the Gulf of Mexico. This fishery takes non-target species or by-catch fauna, mainly teleost fishes, which are incidentally captured. Some of the by-catch species has commercial use and the rest of them are discarded. Therefore, it is important to describe the composition of the discarded fauna, to determine the impacts under the ecosystem approach. Discarding catch of shrimp trawls carried out in 2013 on the continental shelf off the State of Veracruz in different depth intervals (22-46 and > 46 m) was analyzed. For each trawl, the shrimp catch, the commercial by-catch and the discarding were recorded and the catch ratios respect to shrimp, were obtained. A discard sample was taken and the species were identified, the total length was taken and the ecological parameters were calculated. The non-parametric multiple dimensional scaling test was performed. A total of 7,178 fishes were collected from 34 families, 46 genera and 51 species. The ratio of commercial species by-catch: shrimp and discard: shrimp was 15.41:1 and 40:1 kg, respectively. The species with high relative dominance were Citharichthys macrops, Synodus foetens, Diplectrum bivittatum, Rhomboplites aurorubens and Upeneus parvus. The species with greater importance index were C. macrops, S. foetens, and D. bivittatum. The 43.14% of the discarded species are used as food and 7.84% as bait. The maximum diversity (H´) was 3.76 bits ind-1 and the trophic level was 4.31. The study of discard composition is a basis to assess the impact generated by the shrimp trawlers and provides guidelines for identify changes in the community structure.