Resumen Introducción: El bivalvo Anadara tuberculosa es un recurso pesquero y económico importante en el Pacífico Este Tropical. La proporción sexual varia a lo largo de su área de distribución, con casos de aparición de hermafroditismo, ocasional para algunas poblaciones, normal en otras. Estas características podrían ser una respuesta a presiones antropogénicas y ambientales. Objetivo: Evaluar la proporción sexual y el hermafroditismo en la especie en el Pacífico de Panamá. Métodos: Se analizó información reproductiva de A. tuberculosa generada entre 1994 y 2020 para el Golfo de Montijo, así como datos de 2017 para el manglar de David. Se aplicaron procedimientos macroscópicos, contrastados con histológicos y se generó un factor de corrección para ajustar la proporción sexual macroscópica, debido al efecto, sobre la proporción sexual, que ocasiona los organismos indeterminados. Resultados: Para el Golfo de Montijo, la histología indicó una proporción sexual hembra a macho de 1:1 hasta 3.2:1, entre 1994 y 2017, mientras que la macroscopía varió de 1.9:1 a 5.1:1 entre 2004 y 2020. Para el manglar de David, la histología indicó una proporción sexual de 3.7:1, y de 7.9:1 por macroscopía en el 2017. En ambas localidades, especímenes más grandes mostraron mayor variación en la proporción sexual, pese a la técnica implementada, así como hermafroditismo protándrico no casual en el 2017. Conclusiones: La aparición del hermafroditismo protándrico y los cambios en la proporción sexual indican que la población de A. tuberculosa, en ambas localidades, está respondiendo a presiones antropogénicas y ambientales.

Abstract Introduction: The bivalve Anadara tuberculosa is an important fishery in the Eastern Tropical Pacific. The sex ratio varies along its geographic range and there are cases of hermaphroditism, occasional in some populations, normal in others. These characteristics may be a response to anthropogenic and environmental pressure. Objective: To evaluate sex ratio and hermaphroditism of the species in the Panamanian Pacific. Methods: Data on reproductive features of A. tuberculosa generated between 1994 and 2020 for Gulf of Montijo, as well as 2017 data from mangroves of David was analyzed. Macroscopic diagnosis of individual sex is sensitive to the problem of indeterminate individuals, which in turn can skew the sex ratio analysis; therefore, the macroscopic method was compared with histological sections to generate a correction factor to adjust the macroscopically determined sex ratio. Results: For Montijo, histology indicated that the female to male sex ratio ranged from 1:1 to 3.2:1 between 1994 and 2017, while macroscopy indicated 1.9:1 to 5.1:1 between 2004 and 2020. For David, histology indicated a ratio of 3.7:1, and macroscopy 7.9:1. At both localities, larger specimens had more sex ratio variation, independently of the technique, and there was non-casual protandric hermaphroditism in 2017. Conclusion: The occurrence of protandric hermaphroditism and sex ratio changes suggest anthropogenic and environmental pressure in all populations.

RESUMO Mudanças morfoanatômicas ou fisiológicas em conjunto com mudanças no tamanho do corpo, são conhecidas como relações alométricas. O objetivo do estudo foi identificar os pontos de mudanças de crescimento de Centropomus com base na morfometria e morfogeometria dos otólitos. Foram coletados 455 indivíduos de C. undecimalis e 176 de C. parallelus, adquiridos com pescadores artesanais do estado de Alagoas, Brasil. Os otólitos sagitta foram medidos quanto ao comprimento, altura, perímetro, área e pesados. Os modelos potencial e polifásico foram ajustados entre o comprimento do peixe e o comprimento do otólito. Os morfotipos de otólitos são descritos por descritores de Fourier e índices de forma. O modelo polifásico detectou três fases de crescimento. A primeira stanza para C. undecimalis foi em 46,8 cm e a segunda em 75,9 cm. Já C. parallelus, a primeira foi em 18,8 cm e segunda em 41,2 cm. Cada stanza possui um morfotipo específico de otólitos em ambas as espécies. Os otólitos de C. undecimalis e C. parallelus exibiram mudanças alométricas ontogenéticas em seu padrão de crescimento com dois pontos de mudança de stanzas. As stanzas corresponderam a comprimentos específicos alcançados por indivíduos ao longo de seus ciclos de vida, como seu tamanho na maturidade e comprimento na reversão sexual.

ABSTRACT Morphoanatomical or physiological changes coupled with changes in body size are known as allometric relationships. The objective of this study was to identify the points of growth changes in Centropomus based on otolith morphometry and morphogeometry. For this purpose, 455 individuals of C. undecimalis and 176 of C. parallelus were collected from artisanal fishermen of the coast of the state of Alagoas, Brazil. The sagittal otoliths were measured for length, height, perimeter, area and weighed. The potential and polyphasic models were fitted between total fish length and otolith length. The morphotypes otoliths wen describe by form Fourier descriptors and shape indices. The polyphasic model detected three growth phases. The first stanza for C. undecimalis was at 46.8 cm and the second at 75.9 cm. For C. parallelus, it was at 18.8 cm and at 41.2 cm. Each stanza has a specific otoliths morphotype in both species. The otoliths of C. undecimalis and C. parallelus exhibited ontogenetic allometric changes in their growth pattern with two stanzas changing points. The stanzas corresponded to specific lengths reached by individuals over their life cycles, such as their size at maturity and length at sexual reversion.

Abstract The aim of this study was to investigate the spatial and temporal distribution of Exhippolysmata oplophoroides and relate its abundance to various environmental variables (bottom water temperature and salinity, texture of sediment and percentage of dissolved organic matter). The sampling of shrimp and abiotic factors was carried out monthly from July 2012 to June 2014, in seven trawling stations (S1-S7), four of them in the marine area and three in the estuary (southern coast of the state of São Paulo, Brazil). The distribution of individuals showed significant differences between stations and between the two years of study (ANOVA, p < 0.05), but not among seasons (p > 0.05). A total of 2005 shrimp were collected, with the highest abundance being found in S4 (n= 937). Bottom salinity and sediment texture were the environmental factors with significant influence on the distribution of the species in the studied region. The low salinity values at S6 and S7, and the low capacity for osmoregulation of E. oplophoroides limit its distribution in the marine environment. High concentrations of silt+clay found at S4 contributed to the accumulation of organic matter, which influenced the high abundance of shrimp there. The information gathered in our study provides valuable results for the knowledge of this species in its area of distribution and contributes to a better understanding of the life history.

Abstract: Background: the predictability of nectarivorous bats and their greater fecundity efficiency promote specialized pollination systems in columnar cactus in central Mexico. Some authors have suggested the same pollination pattern for Agave genus, and even when recent meta-analysis does not find such pattern, they have suggested this could be due to the lack of descriptive studies of pollination for this genus. Hypothesis: according to the chiropterophily syndrome of its flowers, the most efficient pollinator of Agave horrida will be nectarivorous bats leading to a pollination system with a specialist tendency in this agave species. Studied species: Agave horrida and floral visitors. Study site and years of study: lava field of the Chichinautzin mountain range, in Morelos State in Central Mexico in 2005. Methods: we studied the floral biology of A. horrida, its floral offer (density of flowers in a given area), visitor rate, and visitor abundance, and conducted exclusion experiments for diurnal and nocturnal visitors. Results: A. horrida has protandric flowers with chiropterophilous characteristics (larger nectar production at night and nocturnal anther dehiscence and stigma receptivity). Nectarivorous bats were the most frequent flower visitors and the guild that most frequently presented pollen on their bodies. Pollinator exclusion experiments show that both birds and bats can successfully pollinate A. horrida. Nevertheless, the predictability and abundance of the nectarivorous bat Leptonycteris nivalis, along with the greater fruit and seed production than birds, makes it the most efficient pollinator. Conclusions: our results support the hypothesis of a specialized pollination system towards nectarivorous bats in agaves in central Mexico.

Resumen: Antecedentes: la predictibilidad de murciélagos nectarívoros y su mayor eficiencia en la fecundación de las flores promueven sistemas de polinización especialistas en los cactus columnares del centro de México. Aunque algunos autores han sugerido el mismo patrón en la polinización del género Agave, resultados de meta-análisis recientes no encuentran dicho patrón, sugiriendo que esto se debe a los pocos estudios disponibles sobre polinización de agaves. Hipótesis: de acuerdo al síndrome quiropterófilo de sus flores, el polinizador más eficiente de Agave horrida serían los murciélagos nectarívoros; lo anterior conduciría a un sistema de polinización quiropterófilo en A. horrida. Especies de estudio: Agave horrida y sus visitantes florales. Sitio y años de estudio: Pedregal de la sierra del Chichinautzin, México, en el año 2005. Métodos: estudiamos la biología floral de A. horrida, la tasa de visita y la abundancia de visitantes florales y realizamos experimentos de exclusión de polinizadores. Resultados: A. horrida tiene flores quiropterófilas (producción de néctar, dehiscencia de las anteras y receptividad nocturnas). Los murciélagos nectarívoros son los visitantes florales más abundantes y el gremio que más frecuentemente presenta polen en su cuerpo. Los experimentos de exclusión muestran que aves y murciélagos polinizan a A. horrida. Sin embargo, la predictibilidad y abundancia del murciélago nectarívoro Leptonycteris nivalis, aunado a su mayor producción de frutos y semillas en comparación con las aves lo convierten en el polinizador mas eficiente. Conclusiones: nuestros resultados refuerzan la hipótesis de un sistema de polinización especialista a murciélagos nectarívoros en agaves del centro de México.

RESUMEN La ecología de la polinización de Syagrus orinocensis fue estudiada durante tres períodos reproductivos, en un bosque de piedemonte en Casanare, Orinoquia colombiana. Syagrus orinocensis crece hasta 10m., produce de una a cuatro inflorescencias bisexuales aunque ocasionalmente son unisexuales. Las bisexuales presentan flores estaminadas y pistiladas agrupadas en tríadas, y las unisexuales llevan sólo estaminadas en díadas. Las inflorescencias protándricas abren de día, y permanecieron activas 26 días; la fase masculina se extendió los primeros 15 días, siguió una fase inactiva por ocho días, y finalmente, la fase pistilada por tres días. Las inflorescencias fueron visitadas por 43 especies de insectos de los órdenes Coleoptera, Hymenoptera y Diptera. Los insectos visitaron las inflorescencias en fase masculina, donde buscaban polen y lugares para reproducirse, mientras que en la fase femenina buscaban néctar. Los polinizadores más efectivos fueron abejas meliponinas (Apidae, Meliponini), que transfirieron adherido a su cuerpo el 83 % del polen. La presencia, constancia y eficiencia de abejas durante el estudio son evidencia sólida de melitofilia en palmas. Este caso de melitofilia permitió proponer los criterios para redefinir este tipo de polinización en palmas silvestres neotropicales.

ABSTRACT The pollination ecology of the Syagrus orinocensis was studied in the course of three consecutive yearly flowering seasons in a foothill forest in Casanare, Colombian Orinoco region. Syagrus orinocensis palms grow up to 10 m high and produce one to four bisexual, occasionally unisexual, inflorescences. The bisexual inflorescences bear staminate and pistillate flowers arranged in triads, whereas the unisexual inflorescences carry only staminate flowers in dyads. The inflorescences are protandric and open during daytime, remaining active for 26 days. The male phase extends for the first 15 days, which are followed by 8 days of an inactive phase; the pistillate phase lasts up to three days. The inflorescences of S. orinocensis were visited by 43 species of insects belonging to the orders Coleoptera, Hymenoptera and Diptera. The presence of anthophilous insects was primarily restricted to the male phase of anthesis, during which the visitors searched for pollen and breeding sites; those which visited inflorescences during the female phase seeked out nectar. The most effective pollinators of S. orinocensis were stingless bees (Apidae, Meliponini), as they transferred in average 83% of the pollen that reached receptive inflorescences. The presence, constancy and efficiency of stingless bees during this study constitute solid evidence of melittophily in S. orinocensis and allows us to propose criteria to redefine this pollination syndrome in Neotropical wild palms.

ResumenLos róbalos (C. undecimalis y C. ensiferus) son recursos pesqueros de importancia en toda su área de distribución. En Venezuela son capturados por pesquerías artesanales a lo largo de toda la costa, sin embargo, los estudios sobre su biología que permitan orientar regulaciones de su pesca son escasos. Para analizar aspectos de la reproducción de ambas especies se analizaron 1 325 individuos de C. undecimalis y 2 025 de C. ensiferus, provenientes de la pesca artesanal en la Laguna de Tacarigua, en el norte de Venezuela, desde julio 2009 a septiembre 2010. Se midió la longitud total, peso total, sexo y madurez sexual de cada individuo. La proporción sexual varió a lo largo del año, se observó una diferencia significativa en favor de los machos para C. undecimalis (1:1.5) y de las hembras para C. ensiferus (1:3.3). Se evidenciaron diferencias en la proporción sexual de la talla para ambas especies: los machos dominan las tallas inferiores, mientras que las hembras dominan las superiores. Lo cual señala un patrón típico de hermafroditismo secuencial (protándrico) en ambas. Se estimaron las tallas de madurez sexual (Lm50) para C. undecimalis (♀= 73.6 y ♂= 59.3 cm) y C. ensiferus (♀= 26 y ♂= 21.5 cm). C. ensiferus se reproduce durante todo el año con dos periodos de mayor intensidad (agosto a septiembre y febrero a abril), mientras para C. undecimalis fueron escasos los individuos maduros, mostrando febrero el pico de reproducción más importante. Se encontró diferencia en el crecimiento entre machos y hembras de C. undecimalis: alométrico positivo para hembras (P= 0.0022*L3.353) y negativo para machos (P= 0.0108*L2.945), mientras no se encontraron diferencias para C. ensiferus, que presentó alometría positiva (P= 0.0049*L3.235) para ambos sexos. La falta de regulación y controles de pesca, la evidencia de importantes volúmenes de individuos inmaduros en las capturas, así como el carácter particular de la biología reproductiva de estas especies, sugiere la necesidad de establecer regulaciones para garantizar su aprovechamiento responsable, como un periodo de veda durante el primer trimestre de año y tallas mínimas de captura para ambas especies.

Abstract:Snooks C. undecimalis and C. ensiferus are important fishery resources in their distribution area. In Venezuela they are caught by artisanal fisheries along the entire coast. However, studies on their biology that would help establish fishing regulations are scarce. To study reproduction aspects of these species, we analyzed 1 325 individuals of C. undecimalis and 2 025 of C. ensiferus caught by artisanal fishing in the Laguna de Tacarigua in Northern Venezuela, from July 2009 to September 2010. Total length, total weight, sex and stage of gonadal development were recorded. The sex ratio varied throughout the year: there was a significant difference in favor of C. undecimalis males (1.5:1), and C. ensiferus females (1:3.3). Differences were also evident in the sexual proportion at each size group. For both species, males dominated in the lower size ranges while females dominated in the larger size ranges. These results suggested sequential hermaphroditism (protrandry) in both species. Size at sexual maturity (Lm50) for C. undecimalis was ♀= 73.6 and ♂= 59.3 cm, and ♀= 26 and ♂= 21.5 cm for C. ensiferus. C. ensiferus reproduced throughout the year with two periods of higher intensity (August to September and February to April). Although we found very few mature individuals for C. undecimalis, February showed an important reproduction peak. Growth differences were found between males and females of C. undecimalis: positive allometry for females (P= 0.0022*L3.353) and negative allometry for males (P= 0.0108*L2.945). Both males and females of C. ensiferus showed a positive allometric relationship (P= 0.0049*L3.235). Lack of fishing regulations and controls, evidenced in this study by significant volumes of immature individuals in the catches, and the particular reproductive biology of these species, strongly indicates the need to establish regulations to ensure their responsible use. We recommend establishing a closed season during the first quarter of the year and minimum catch sizes for both species. Rev. Biol. Trop. 65 (1): 181-194. Epub 2017 March 01.

From the evaluation floral morphology, reproductive phenology, floral biology, floral visitors and pollinator’s definition, the reproduction strategy of a Syagrus smithii (Arecaeae) in a Colombian Amazonia region was described. Syagrus smithii palms grow up to 10 m high and produce one to three bisexual inflorescences. The bisexual inflorescences bear staminate and pistillate flowers arranged in triads with a female central flower and two male sides. The inflorescences are protandric and open during daytime, remaining active for 28 days. The male phase extends for the first 14 days, which are followed by 10 days of an inactive phase; the pistillate phase lasts up to four days. The inflorescences of S. smithii were visited by 37 species of insects belonging to the orders Coleoptera, Hymenoptera and Diptera. All visitors get to the flowers in searching of abundant pollen, floral tissues that feed them and as sites of reproduction. The most effective pollinators of S. smithii were Mystrops sp nov. 2 and Mystrops sp nov. 3 (Nitudiladae: Coleoptera), and Microstates sp.2 and Sibinia sp. 1 (Curculionidae: Coleoptera) were secondary pollinators. Since all species of major pollinators have developed their life cycles into inflorescences, we suggest the existence of a specialized system and mutual dependence between pollinators and the palm, which ensures the presence of pollinators throughout the year and individuals with viable seeds

A partir de la evaluación de la morfología floral, la fenología reproductiva, la biología floral, los visitantes florales y determinación de polinizadores se describe la estrategia de polinización de una población de la palma Syagrus smithii de la Amazonia colombiana. Syagrus smithii es una palma solitaria de hasta 10 m de alto; produjo de una a tres inflorescencias bisexuales, con flores estaminadas y pistiladas agrupadas en tríadas, con una flor central femenina y dos laterales masculinas. Las inflorescencias abrieron de día y las flores estuvieron activas de noche. Una inflorescencia permaneció activa en promedio 28 días; la fase masculina se extendió durante los primeros 14 días, seguida de una fase inactiva de 10 días, y la fase final pistilada por cuatro días. En fase masculina, las inflorescencias fueron visitadas por 37 y en fase femenina por 21 especies de insectos, principalmente de los órdenes Coleoptera‚ Hymenoptera y Diptera. Los visitantes accedieron en busca de polen y lugar para reproducción. De todos los visitantes‚ pocas especies fueron polinizadores. Los valores de los índices (IVIP) e (IRP) indicaron que Mystrops sp. nov. 2 y Mystrops sp nov. 3 (Nitidulidae: Coleoptera) fueron los principales polinizadores, mientras que especies de coleópteros como Microstates sp.2 y Sibinia sp. 1 fueron polinizadores secundarios. Dado que los polinizadores desarrollaban sus ciclos de vida en las inflorescencias‚ sugerimos la existencia de un sistema de mutua dependencia entre polinizadores y la palma, el cual asegura la presencia de los polinizadores a lo largo del año y palmas con semillas viables

O controle do sexo dos peixes é uma técnica promissora na aquicultura, pois permite obter vantagens associadas a um dos sexos. Sendo assim, o objetivo deste trabalho foi avaliar o efeito do hormônio 17β-estradiol (E2) na feminização, crescimento e sobrevivência de juvenis de robalo-flecha (Centropomus undecimalis). Durante 45 dias, os juvenis foram submetidos a três dietas (controle, 50, 100 mg E2 kg-1 de ração) com três repetições cada. Após este período, os peixes passaram a ser alimentados somente com ração comercial sem adição de hormônio. Durante o período de administração do E2, os peixes do controle cresceram mais que os dos outros tratamentos. No final do experimento, no tratamento com 50 mg E2 kg-1, 26% dos peixes eram machos, 68.42% eram fêmeas e 5.26% eram intersexo. No tratamento com 100 mg E2 kg-1, 10% dos peixes eram machos e 90% eram fêmeas. Após 11 meses não houve diferença de crescimento entre os tratamentos. Este trabalho mostrou que é possível obter 90% de fêmeas de robaloflecha utilizando rações com 100 mg E2 kg-1 durante 45 dias sem danos ao crescimento ou à sobrevivência.

Sex control in fish is a promising technique for aquaculture, since it gives advantages associated with one sex. The aim of this study was to investigate the feminization of common snook (Centropomus undecimalis) by oral administration of two doses of estradiol-17β (50 and 100 mg E2 kg-1 feed) and control treatment for 45 days and to evaluate their effects on the sex ratio, growth and survival of common snook juveniles. After this period, fish were fed only with commercial feed without hormone supplementation. During the period of E2 administration, the control fish grew more than those in the other treatments. At the end of the experiment in the treatment with 50 mg E2 kg-1, 26.32% of the fish were male, 68.42% were female, and 5.26% were intersex. In the treatment with 100 mg E2 kg-1, 10% of the fish were male, and 90% were female. There was no difference in growth among the treatments after 11 months. This study showed that it is possible to obtain 90% common snook females using feeds with 100 mg E2 kg-1 for 45 days without impairing the fish growth or survival.

The reproductive cycle, recruitment and maturity size of the mangrove cockle Anadara tuberculosa was studied between August 2009 and August 2010 at the 4 departments of the Colombian Pacific coast. Biological samples were collected on three 50 m² plots of each region following the traditional method of capture. To determine the state of sexual development, monthly macro and microscopy (using standard histological techniques) observations were performed. The reproductive cycle was divided in 4 stages, resting, development, maturity and spawning. Spawning events were evident throughout the study period, with higher reproductive activity between December and March, and a second short event between June and August. The average maturity size (46.68 ± 9.29 mm) and mean first maturity size (43.50 mm) are below the minimum legal size of capture (50.00 mm) in Colombia. Temporal variation of reproductive activity and recruitment shows no evidence of sexual maturity synchrony in the Colombian Pacific, important for the establishment of management strategies of the resource. Three percent of hermaphroditism was found which is considered protandric due to the imbalance of sex ratio between females and males (2.46:1) and size difference between sexes.

Se estudió el ciclo reproductivo, reclutamiento y tallas de madurez de la piangua Anadara tuberculosa entre agosto de 2009 y agosto de 2010 en cuatro departamentos de la costa Pacífica colombiana. Se realizaron muestreos biológicos en 3 parcelas de 50 m² para cada región, siguiendo la metodología tradicional de captura. Para determinar el estado de desarrollo sexual, mensualmente se realizaron observaciones macroscópicas e histología rutinaria. Para el análisis reproductivo se definieron los estados de reposo, desarrollo, madurez y desove. Eventos de desove fueron evidentes durante todo el tiempo de estudio, con mayor actividad reproductiva entre diciembre y marzo, y otro evento corto entre junio y agosto. En términos generales, las tallas medias de madurez sexual (46,68 ± 9,29 mm) y de primera madurez (43,50 mm), están por debajo de la talla mínima legal de captura (50,00 mm) en Colombia. La variación temporal de la actividad reproductiva y del reclutamiento, muestra que no se presenta una sincronía de madurez sexual evidente en el Pacífico colombiano, lo cual es información importante para establecer estrategias de manejo del recurso. Se presentó el 3% de hermafroditismo, considerado protándrico, debido a las diferencias en proporción sexual entre hembras y machos (2,46:1) y a la diferencia de tallas entre sexos.

Samples (N = 1065) of the gilthead seabream, Sparus aurata, were collected in the Gulf of Gabes (Tunisia) from March 2008 to February 2010. This species is a protandric hermaphrodite. Total length (TL) ranged from 10.10 to 35.00 cm and the number of males to each female was 1.18:1. The reproductive season extended from October to February and maximum spawning activity occurred from December to January. The size at which 50% of the males reached maturity was 17.63 ± 0.28 cm TL and the size at which 50% of males transformed into females was 18.75 ± 0.19 cm TL. The length-weight relationship for all individuals was described by the following parameters: a = 0.0107 and b = 3.0797. Age of fish ranged from 0 to 8 years. Estimates of the von Bertalanffy growth parameters for the whole sample were: L∞ = 38.28 cm, k = 0.202 year-1, and t0 = -1.888 years.

Se recolectaron muestras (N = 1065) de la dorada, Sparus aurata, en el golfo de Gabes (Túnez) de marzo de 2008 a febrero de 2010. Esta especie es una hermafrodita protándrica. La longitud total (LT) varió de 10.10 a 35.00 cm y el número de machos por cada hembra fue de 1.18:1. La temporada reproductiva se extendió de octubre a febrero y la máxima actividad reproductiva se presentó de diciembre a enero. La talla a la cual el 50% de los machos alcanzó la madurez sexual fue de 17.63 ± 0.28 cm LT y el tamaño al cual el 50% de los machos se transformó en hembras fue de 18.75 ± 0.19 cm LT. La relación longitud-peso para todos los individuos fue descrita por los siguientes parámetros: a = 0.0107 y b = 3.0797. Se encontraron peces de 0 a 8 años de edad. Las estimaciones de los parámetros de crecimiento de von Bertalanffy para toda la muestra fueron: L∞ = 38.28 cm, k = 0.202 año-1 y t0 = -1.888 años.

The barbouriid shrimp Janicea antiguesis (Chace, 1972) is reported from Porto de Galinhas and Tamandaré in Pernambuco and Guarapari in Espírito Santo, Brazil. These records confirm the presence of J. antiguensis in northeastern and eastern Brazil, considerably extending its Brazilian range from Fernando de Noronha to southern Espírito Santo and also representing the first record of this species from mainland coastal reefs. In Brazil, J. antiguensis occurs in or near marine reef caves, typically at depths between 5 and 15 m, and can be most easily observed while scuba diving at night. Colour photographs of J. antiguensis from various Atlantic localities are provided and its colour pattern is compared to that of the closely related Indo-West Pacific barbouriid shrimp, Parhippolyte misticia (Clark, 1989). Some in situ observations are provided for the Porto de Galinhas population of J. antiguensis. Multiple observations of pairs with both individuals brooding embryos at different developmental stages suggest protandric simultaneous hermaphroditism in J. antiguensis.

Crepidula coquimbensis is a protandric marine gastropod with direct development and restricted mobility, which only inhabits inside of empty shells of other marine gastropods cohabiting with hermit crabs of the genus Pagurus. In this study, we report potential dispersal mechanisms of C. coquimbensis and the effect on its population genetic distance and structure, using the gene COI, in three localities of northern Chile. The results suggested that C. coquimbensis shows high levels of genetic differentiation at local scale, and the association with P. edwardsi would be its only one mechanism of dispersal.

Aulonemia aristulata (Döll) McClure é uma espécie de bambu lignificado endêmico do Brasil. Esta espécie ocorre em florestas do sudeste e pode atingir altas densidades em bordas de floresta e dominar o sub-bosque de manchas de floresta que tiveram o dossel perturbado. O objetivo deste estudo foi descrever o período de florescimento, a biologia floral, a frutificação e o recrutamento de plântulas de A. aristulata, em condições naturais, em duas áreas localizadas em um segmento de FlorestaAtlântica. Foram registrados dados sobre a morfologia das sinflorescências e das espiguetas, tempo e sequência de eventos de antese e visitantes florais. Foram também verificadas a polinização natural (polinização aberta e controle) e a autopolinização espontânea.Aviabilidade do pólen foi estimada usando a técnica de acetocarmim. Aulonemia aristulata é monocárpica (semélpara) com floração gregária. Todos os colmos em ambas as populações estudadas floresceram e frutificaram entre agosto e novembro de 2007 e, subsequentemente, morreram entre dezembro de 2007 e abril de 2008. Dois tipos de sinflorescências foram observadas: terminais com antécios bissexuais e protândricos com antese de 3-4 dias e axilares com antécios bissexuais, mas funcionalmente femininos e com antese de 3-4 dias.As últimas foram observadas no rizoma de plantas das quais a porção aérea foi removida. A presença de sinflorescências axilares com flores pistiladas é descrita aqui pela primeira vez em espécies de Aulonemia. Além disso, este é o primeiro relato de ginomonoicia em bambus lignificados. A frutificação sob condições naturais (35%) foi superior à obtida nas sinflorescências ensacadas (11,5%). A produção de frutos originados das flores femininas foi cerca de 20%. A viabilidade do pólen foi de cerca de 90%. O conjunto de resultados obtidos sugere que Aulonemia aristulata é anemófila. O recrutamento massivo de plântulas, observado após a morte, associado à habilidade de colonizar áreas abertas poderá promover a regeneração de Aulonemia aristulata.

Aulonemia aristulata (Döll) McClure is a lignified bamboo species endemic to Brazil. This species occurs in southeastern forests and can reach high density at forest edges, dominating the understory of canopy-disturbed forest patches. The goal of this study was to describe the flowering period, floral biology, fruiting and seedling recruitment of A. aristulata in natural conditions in two areas located in a segment of the Atlantic Forest. Data on the morphology of the synflorescences and florets, timing and sequence of the anthesis events and floral visitors were recorded. Natural pollinators (open pollination or control) as well as spontaneous self-pollination were also checked. Pollen viability was estimated using the acetocarmine technique. Aulonemia aristulata is monocarpic (semelparous) with gregarious flowering. All culms in both studied areas blossomed and fruited between August and November 2007, dying subsequently between December 2007 and April 2008. Two types of synflorescences and flowers were observed: terminal with bisexual and protandric florets, with the anthesis lasting for 3-4 days; and axillary, with morphologically bisexual, but functionally female, florets and anthesis lasting for 3-4 days. The latter were also observed in the rhizome of plants whose aerial portion had been removed. The presence of axillary synflorescences with pistillate flowers is described here for the first time in Aulonemia species. Moreover, this is the first report of gynomonoecy in woody bamboo. Fruiting from bisexual florets under natural conditions (35%) was superior to that obtained from bagged synflorescences (11.5%). Fruiting from functional female florets was around 20%. Pollen viability was on the average of 90%. The results suggest that Aulonemia aristulata is anemophilous. The massive bamboo seedling recruitment observed after dieback with the ability to colonize open areas could promote the regeneration of Aulonemia aristulata.

A population of the river shrimp Potimirim mexicana from the Máquinas River in Veracruz, Mexico, was analyzed. The pattern of size distribution by sex in this species suggests that it is a sequential hermaphrodite. A discriminant analysis method applied to establish the subgroups that are part or the population showed the existence of 3 classes: sexually undifferentiated organisms, males and females. Within the male subgroup 3 types or organisms were established depending on the length of the appendix masculina. With this analysis it is confirmed that P. mexicana is a species with sequential hermaphroditism.

Se analizó una población del camaroncito de río Potimirim mexicana obtenida del río Máquinas en el estado de Veracruz, México. Esta especie presenta una distribución de tallas por sexo que sugiere que se trata de una especie con hermafroditismo secuencial. Se aplicó el método de análisis discriminante para establecer los subgrupos que conforman la población, dando como resultado 3 clases: organismos sexualmente indeterminados, machos y hembras. En el subgrupo de los machos se establecieron 3 conjuntos, con base en el tamaño del appendix masculina. Mediante este análisis se confirmó que P. mexicana es una especie hermafrodita secuencial.

Una pregunta importante en la ecología de reproducción es ¿por qué hay sexos separados en algunas especies pero hermafroditismo en otras? Este artículo está enfocado en un sistema sexual recientemente descrito, hermafroditismo simultáneo protándrico (HSP), en camarones "limpiadores" del género Lysmata. En este sistema, los individuos maduran primero en una fase masculina (FM) pero más tarde cambian a una fase femenina (FF). Aunque los individuos FF producen embriones como si fueran hembras, también retienen los ductos masculinos y producen esperma. Los FF son hermafroditas simultáneos que pueden copular como machos y fertilizar otros FF pero no pueden autofertilizarse. Es posible que el tamaño (edad) de cambio de FM a FF sea dependiente de la abundancia relativa de los FM y FF en la población (determinación ambiental de sexo). Dada la amplia variación de los atributos socioecológicos entre especies de Lysmata, es difícil proponer una sola fuerza selectiva que pueda explicar la evolución de HSP. Se propone una hipótesis basada en la historia evolutiva de Lysmata. Se sugiere que el HSP no ocurre en otros grupos de carideos porque evolucionó bajo circunstancias únicas a Lysmata ("contingencia histórica"). Para entender este raro sistema sexual, hay que estudiar en detalle la ecología, etología y filogenia de Lysmata.

An important question in reproductive ecology is: why are there separate sexes in some species but hermaphroditism in others? The focus of this paper is on a recently-described sexual system, protandric simultaneous hermaphroditism (PSH), in cleaner shrimps of the genus Lysmata. An individual first matures in a male phase (MP) but later changes to a female phase (FP). Although an FP produces embryos like a female, it also retains the male ducts and produces sperm. The FPs are simultaneous hermaphrodites that can copulate like males and fertilize other FP’s but they cannot self-fertilize. It is possible that the size (age) of change from MP to FP is dependent on the relative abundance of MPs and FPs in the population (environmental sex determination). Given the variation in socioecological attributes in Lysmata, it is difficult to propose a single selective pressure that explains the evolution of PSH. A hypothesis is proposed based on evolutionary history. It is suggested that PSH does not occur in other caridean groups because it evolved under unique circumstances in Lysmata ("historical contingency"). In order to understand this rare sexual system, it will be necessary to study in detail the ecology, behavior and phylogeny of Lysmata.

Uma pergunta importante na ecologia da reprodução é: por quê há sexos separados em algumas espécies mas hermafroditismo em outras? Este artigo está enfocado em um sistema sexual recentemente descrito, hermafroditismo simultâneo protândrico (HSP), em camarões "limpadores" do gênero Lysmata. Neste sistema, os indivíduos maduram primeiro em uma fase masculina (FM) mas, mais tarde mudam a uma fase feminina (FF). Ainda que os indivíduos FF produzem embriões como se fossem fêmeas, também retêm os dutos masculinos e produzem esperma. Os FF são hermafroditas simultâneos que podem copular como machos e fertilizar outros FF mas não podem auto-fertilizar-se. É possível que o tamanho (idade) de mudança de FM a FF seja dependente da abundância relativa dos FM e FF na população (determinação ambiental de sexo). Dada a ampla variação dos atributos socio-ecológicos entre espécies de Lysmata, é difícil propor uma só força seletiva que possa explicar a evolução de HSP. Propõe-se uma hipótese baseada na história evolutiva de Lysmata. É sugerido que o HSP não ocorre em outros grupos de carídeos porque a Lysmata evoluiu sob circunstâncias únicas ("contingência histórica"). Para entender este raro sistema sexual, há que estudar em detalhe a ecologia, etiologia e filogenia de Lysmata.