RESUMO
Our knowledge of the mating systems in burrowing shrimps (infraorders Axiidea and Gebiidea) is still rather limited. Here we describe the burrow use pattern, sex ratio, and sexual dimorphism of the burrowing shrimp Axianassa australis to test for monogamy, considering that monogamous species live in heterosexual pairs and exhibit a low degree of sexual dimorphism. To this end, a total of 226 individuals of A. australis were collected from the northeast region of Brazil. Our results showed that A. australis inhabited its burrows mainly as pairs, most of which were male-female pairs. In agreement with the expectations, specimens of A. australis were found dwelling as heterosexual pairs more frequently than expected by chance alone. The presence of ovigerous females was associated with the burrow occupation; that is, brooding females were more frequently observed in male-female combinations than solitarily. Also supporting theoretical considerations, we did not observe sexual dimorphism in body size between males and females of the population and the different categories of the burrow occupation. Conversely, sexual dimorphism in cheliped size was evident in the population, with larger chelipeds in males than in females. This observation agrees with that reported for most burrowing shrimps in which male-male competition is the main evolutionary force of sexual selection. The observations above favor the hypothesis that A. australis is primarily monogamous, with a small fraction of the males moderately promiscuous.
Assuntos
Decápodes , Animais , Evolução Biológica , Tamanho Corporal , Brasil , Feminino , Humanos , Masculino , ReproduçãoRESUMO
Hernáez et al. (2020) described a new species of ghost shrimp, Neocallichirus pinheiroi, from northeastern coast of Brazil, Western Atlantic. Although the description and figures presented by Hernáez et al. (2020) fully characterize the new species, the journal issue in which the description appeared was published online only, and the article in which N. pinheiroi appeared did not include a ZooBank registration number (LISD), required for validation of new names in electronic-only publications [vide Art. 8.5.3 of the amended Code of the International Commission on Zoological Nomenclature (ICZN, 1999, 2012)]. As result, the name Neocallichirus pinheiroi Hernáez, Windsor, Paula Santana, 2020, is not available according the International Code of Zoological Nomenclature (ICZN, 1999, 2012). Therefore, the present note serves to validate the name Neocallichirus pinheiroi by fulfilling the ICZN conditions for nomenclatural availability.
Assuntos
Decápodes , AnimaisRESUMO
Hernáez et al. (2020) described a new fossil species of ghost shrimp, Callichirus santensis, from the Upper Pleistocene Cananéia Formation, southeast Brazil. The article in which C. santensis was originally proposed was published online only (Hernáez et al., 2020), but did not include a ZooBank registration number (LISD), required for validation of the new names in electronic-only publications [vide Art. 8.5.3 of the amended Code of the International Commission on Zoological Nomenclature (ICZN, 1999, 2012)]. Therefore, the present note serves to validate the name Callichirus santensis by fulfilling the ICZN conditions for nomenclatural availability.
Assuntos
Decápodes , Animais , FósseisRESUMO
A new species of intertidal ghost shrimp, Biffarius botterae, is described from Maranhão and Ceará in northeastern Brazilian coast. Diagnostic features of the new species include: (1) antennular peduncle shorter than antennal peduncle; (2) male major cheliped massive; (3) male pleopod 2 uniramous, vestigial; (4) uropodal endopod widening distally, inner lateral margin convex; and (5) anterodorsal plate of uropodal exopod absent. Biffarius Manning Felder, 1991, now consists of four species: B. biformis (Biffar, 1971), B. botterae sp. nov., B. delicatulus Rodrigues Manning, 1992, and B. limosus (Poore, 1975). A key to the species of Biffarius is provided.
Assuntos
Decápodes , Distribuição Animal , Estruturas Animais , Animais , Brasil , MasculinoRESUMO
La mortalidad por pesca ha sido pocas veces estudiada aislando el efecto causado por las capturas. En este estudio se analizó este aspecto usando como modelo biológico al camarón fantasma Callichirus major (Say, 1818), el cual es colectado intensamente en varias regiones de la costa de Brasil. Para ello, la densidad de las galerías y la demografía poblacional de C. major fue analizada en las playas de Gonzaga e Itararé, dos playas contiguas del Estado de São Paulo, Brasil. La playa de Gonzaga fue considerada como control debido a que desde 1992 una ley municipal impide las capturas de C. major, mientras que Itararé fue considerada como tratamiento ya que en este lugar este camarón es recolectado durante todo el año. Los resultados mostraron que la densidad de las galerías y el tamaño de las hembras fueron significativamente mayores en la playa de Gonzaga que en Itararé. En Itararé, la proporción sexual no mostró diferencias significativas de la relación 1:1, lo cual no se ajustó a lo observado en el área sin mortalidad por pesca y al patrón general reportado en otras especies de camarones fantasma del mundo en donde las hembras predominan sobre los machos. El potencial reproductivo fue significativamente menor en Itararé, como efecto del menor número de hembras presentes en esta área sometida a la pesca intensiva de camarones. De acuerdo con una estimativa inicial, un 71% de los individuos murieron por efecto de la pesca en Itararé. Esto hace inviable el sostenimiento ambiental de C. major en esta área dada la actual presión de extracción. La presencia de C. major en la playa de Itararé y probablemente en otras áreas próximas donde es capturada, estaría favorecida por el permanente suministro de larvas procedentes de la playa de Gonzaga, en Santos, que está protegida por ley y fiscalización municipal.(AU)
Studies on mortality due to fishing based on isolating the effect caused by catches are scarce. The present study analyzed this aspect using the ghost shrimp Callichirus major (Say, 1818) as a biological model, which is heavily harvested along the Brazilian coast. For that purpose, density of burrows and population structure of C. major was examined at two adjacent beaches, Gonzaga and Itararé, from the State of São Paulo, Brazil. Gonzaga beach was considered as control because since 1992 a municipal law prevents the capture of C. major, whereas Itararé as treatment since in this place the species is harvested throughout the year. Burrow density and female CL size were significantly higher in Gonzaga than that Itararé. Sex-ratio did not differ significantly from 1:1 in Itararé, differing from the observed in the area without fishing mortality and also to the general pattern reported in other species of ghost shrimps in which females outnumbered than males. Reproductive potential was significantly smaller in Itararé than Gonzaga, as result of the reduced number of females present in this area relative to Gonzaga. A preliminary estimation indicates that 71 % of shrimps in Itararé died as result of fishing. This information suggests non-viability of C. major in this area given the current pressure of fishing. Presence of C. major in the beach of Itararé and probably in other nearby areas where exploitation occurs would be favored by the permanent supply of larvae from Gonzaga beach where the species is protected by and municipal surveillance.(AU)
Assuntos
Animais , Artemia , Conservação dos Recursos Naturais/legislação & jurisprudência , MortalidadeRESUMO
La mortalidad por pesca ha sido pocas veces estudiada aislando el efecto causado por las capturas. En este estudio se analizó este aspecto usando como modelo biológico al camarón fantasma Callichirus major (Say, 1818), el cual es colectado intensamente en varias regiones de la costa de Brasil. Para ello, la densidad de las galerías y la demografía poblacional de C. major fue analizada en las playas de Gonzaga e Itararé, dos playas contiguas del Estado de São Paulo, Brasil. La playa de Gonzaga fue considerada como control debido a que desde 1992 una ley municipal impide las capturas de C. major, mientras que Itararé fue considerada como tratamiento ya que en este lugar este camarón es recolectado durante todo el año. Los resultados mostraron que la densidad de las galerías y el tamaño de las hembras fueron significativamente mayores en la playa de Gonzaga que en Itararé. En Itararé, la proporción sexual no mostró diferencias significativas de la relación 1:1, lo cual no se ajustó a lo observado en el área sin mortalidad por pesca y al patrón general reportado en otras especies de camarones fantasma del mundo en donde las hembras predominan sobre los machos. El potencial reproductivo fue significativamente menor en Itararé, como efecto del menor número de hembras presentes en esta área sometida a la pesca intensiva de camarones. De acuerdo con una estimativa inicial, un 71% de los individuos murieron por efecto de la pesca en Itararé. Esto hace inviable el sostenimiento ambiental de C. major en esta área dada la actual presión de extracción. La presencia de C. major en la playa de Itararé y probablemente en otras áreas próximas donde es capturada, estaría favorecida por el permanente suministro de larvas procedentes de la playa de Gonzaga, en Santos, que está protegida por ley y fiscalización municipal.
Studies on mortality due to fishing based on isolating the effect caused by catches are scarce. The present study analyzed this aspect using the ghost shrimp Callichirus major (Say, 1818) as a biological model, which is heavily harvested along the Brazilian coast. For that purpose, density of burrows and population structure of C. major was examined at two adjacent beaches, Gonzaga and Itararé, from the State of São Paulo, Brazil. Gonzaga beach was considered as control because since 1992 a municipal law prevents the capture of C. major, whereas Itararé as treatment since in this place the species is harvested throughout the year. Burrow density and female CL size were significantly higher in Gonzaga than that Itararé. Sex-ratio did not differ significantly from 1:1 in Itararé, differing from the observed in the area without fishing mortality and also to the general pattern reported in other species of ghost shrimps in which females outnumbered than males. Reproductive potential was significantly smaller in Itararé than Gonzaga, as result of the reduced number of females present in this area relative to Gonzaga. A preliminary estimation indicates that 71 % of shrimps in Itararé died as result of fishing. This information suggests non-viability of C. major in this area given the current pressure of fishing. Presence of C. major in the beach of Itararé and probably in other nearby areas where exploitation occurs would be favored by the permanent supply of larvae from Gonzaga beach where the species is protected by and municipal surveillance.
Assuntos
Animais , Artemia , Conservação dos Recursos Naturais/legislação & jurisprudência , MortalidadeRESUMO
RESUMEN La mortalidad por pesca ha sido pocas veces estudiada aislando el efecto causado por las capturas. En este estudio se analizó este aspecto usando como modelo biológico al camarón fantasma Callichirus major (Say, 1818), el cual es colectado intensamente en varias regiones de la costa de Brasil. Para ello, la densidad de las galerías y la demografía poblacional de C. major fue analizada en las playas de Gonzaga e Itararé, dos playas contiguas del Estado de São Paulo, Brasil. La playa de Gonzaga fue considerada como control debido a que desde 1992 una ley municipal impide las capturas de C. major, mientras que Itararé fue considerada como tratamiento ya que en este lugar este camarón es recolectado durante todo el año. Los resultados mostraron que la densidad de las galerías y el tamaño de las hembras fueron significativamente mayores en la playa de Gonzaga que en Itararé. En Itararé, la proporción sexual no mostró diferencias significativas de la relación 1:1, lo cual no se ajustó a lo observado en el área sin mortalidad por pesca y al patrón general reportado en otras especies de camarones fantasma del mundo en donde las hembras predominan sobre los machos. El potencial reproductivo fue significativamente menor en Itararé, como efecto del menor número de hembras presentes en esta área sometida a la pesca intensiva de camarones. De acuerdo con una estimativa inicial, un 71% de los individuos murieron por efecto de la pesca en Itararé. Esto hace inviable el sostenimiento ambiental de C. major en esta área dada la actual presión de extracción. La presencia de C. major en la playa de Itararé y probablemente en otras áreas próximas donde es capturada, estaría favorecida por el permanente suministro de larvas procedentes de la playa de Gonzaga, en Santos, que está protegida por ley y fiscalización municipal.
ABSTRACT Studies on mortality due to fishing based on isolating the effect caused by catches are scarce. The present study analyzed this aspect using the ghost shrimp Callichirus major (Say, 1818) as a biological model, which is heavily harvested along the Brazilian coast. For that purpose, density of burrows and population structure of C. major was examined at two adjacent beaches, Gonzaga and Itararé, from the State of São Paulo, Brazil. Gonzaga beach was considered as control because since 1992 a municipal law prevents the capture of C. major, whereas Itararé as treatment since in this place the species is harvested throughout the year. Burrow density and female CL size were significantly higher in Gonzaga than that Itararé. Sex-ratio did not differ significantly from 1:1 in Itararé, differing from the observed in the area without fishing mortality and also to the general pattern reported in other species of ghost shrimps in which females outnumbered than males. Reproductive potential was significantly smaller in Itararé than Gonzaga, as result of the reduced number of females present in this area relative to Gonzaga. A preliminary estimation indicates that 71 % of shrimps in Itararé died as result of fishing. This information suggests non-viability of C. major in this area given the current pressure of fishing. Presence of C. major in the beach of Itararé and probably in other nearby areas where exploitation occurs would be favored by the permanent supply of larvae from Gonzaga beach where the species is protected by and municipal surveillance.
RESUMO
Callichirus seilacheri (Bott, 1955) is considered one of the most common ghost shrimps in the intertidal zone of sandy beaches along the eastern tropical Pacific. The present study provides new observations on the morphology of C. seilacheri, based on the revision of abundant material collected along the Pacific coast of Central America, including specimens from the type locality (Playa Los Blancos, El Salvador) of this species. The new features of C. seilacheri include: carapace with low triangular rostrum, without setae on tip; pereiopod 1 highly dissimilar in adult males, but not in females and juveniles of both sexes; first pleopod sexually dimorphic; females with oval gonopores, each one of them on the ventral coxal segment of the third pereiopod, and extra genital pores on the ventral coxal segment of the fifth pereiopod, these latter non-functional (non connected with the ovaries). Apparently, the presence of extra gonopores in females of C. seilacheri is a vestigial character shared with other representatives of the same genus.(AU)
Callichirus seilacheri (Bott, 1955) é considerado um dos camarões-fantasmas mais comuns em zonas intertidais de praias arenosas, ao longo do Pacífico oriental tropical. O presente estudo fornece novas observações sobre a morfologia de C. seilacheri, com base numa revisão de material abundante coletado ao longo da costa do Pacífico, na América Central, incluindo espécimes da localidade tipo desta espécie (Playa Los Blancos, El Salvador). As características inéditas de C. seilacheri, incluem: carapaça com pequeno rostro triangular, e sem cerdas na extremidade; Pereiópodos 1 muito desiguais em machos adultos, mas não nas fêmeas e juvenis, de ambos os sexos; Primeiro pleópodo sexualmente dimórfico; Fêmeas com gonóporos ovais, cada um na porção ventral da coxa do terceiro par de pereiópodos, e poros genitais extras na porção ventral da coxa do quinto pereiópodo, estes últimos não funcionais (não conectados aos ovários). Aparentemente, a presença de gonóporos extras em fêmeas de C. seilacheri é um caráter vestigial, compartilhado com outros representantes do mesmo gênero.(AU)
Assuntos
Animais , Decápodes/anatomia & histologia , Decápodes/ultraestrutura , Constituição Corporal , Praias , Achados Morfológicos e Microscópicos , CostaRESUMO
Callichirus seilacheri (Bott, 1955) is considered one of the most common ghost shrimps in the intertidal zone of sandy beaches along the eastern tropical Pacific. The present study provides new observations on the morphology of C. seilacheri, based on the revision of abundant material collected along the Pacific coast of Central America, including specimens from the type locality (Playa Los Blancos, El Salvador) of this species. The new features of C. seilacheri include: carapace with low triangular rostrum, without setae on tip; pereiopod 1 highly dissimilar in adult males, but not in females and juveniles of both sexes; first pleopod sexually dimorphic; females with oval gonopores, each one of them on the ventral coxal segment of the third pereiopod, and extra genital pores on the ventral coxal segment of the fifth pereiopod, these latter non-functional (non connected with the ovaries). Apparently, the presence of extra gonopores in females of C. seilacheri is a vestigial character shared with other representatives of the same genus.
Callichirus seilacheri (Bott, 1955) é considerado um dos camarões-fantasmas mais comuns em zonas intertidais de praias arenosas, ao longo do Pacífico oriental tropical. O presente estudo fornece novas observações sobre a morfologia de C. seilacheri, com base numa revisão de material abundante coletado ao longo da costa do Pacífico, na América Central, incluindo espécimes da localidade tipo desta espécie (Playa Los Blancos, El Salvador). As características inéditas de C. seilacheri, incluem: carapaça com pequeno rostro triangular, e sem cerdas na extremidade; Pereiópodos 1 muito desiguais em machos adultos, mas não nas fêmeas e juvenis, de ambos os sexos; Primeiro pleópodo sexualmente dimórfico; Fêmeas com gonóporos ovais, cada um na porção ventral da coxa do terceiro par de pereiópodos, e poros genitais extras na porção ventral da coxa do quinto pereiópodo, estes últimos não funcionais (não conectados aos ovários). Aparentemente, a presença de gonóporos extras em fêmeas de C. seilacheri é um caráter vestigial, compartilhado com outros representantes do mesmo gênero.
Assuntos
Animais , Constituição Corporal , Decápodes/anatomia & histologia , Decápodes/ultraestrutura , Achados Morfológicos e Microscópicos , Costa , PraiasRESUMO
Se examinó la distribución espacial y la producción de huevos de langostillas depositados en la colección del Museu de Zoologia de la Universidade de São Paulo (MZUSP), Brasil. Para ello, se analizaron 1.346 ejemplares, de los cuales 169 correspondieron a hembras ovígeras. Las hembras ovígeras estuvieron distribuidas en diez especies de Munididae y tres de Munidopsidae. Once de las trece especies estudiadas se distribuyeron en la costa brasilera, mientras que dos en otras regiones marinas. El análisis de la distribución batimétrica reveló la presencia de cuatro especies de langostillas sobre la plataforma continental ( 200 m: M. spinifrons, M. pusilla, M. irrasa, M. flinti), dos en la primera franja del talud continental (200-500 m: Munida forceps, A. longipes) y cinco distribuidas entre 500 y 1048 m de profundidad (M. erinacea, M. constricta, M. valida, M. microphthalma, M. transtridens). En general, las especies de Munididae produjeron una alta cantidad de huevos (554 ± 619 huevos) de pequeño tamaño (0,48 ± 0,120 mm) comparado con las especies de Munidopsidae (13 ± 10 huevos; 1,12 ± 0,337 mm, respectivamente). Esta tendencia es consistente con la filogenia de ambos clados cuyo origen en común se refleja en similitudes morfológicas tanto en las formas larvales como en las adultas, pero no así en la estrategia reproductiva que claramente separa las especies pertenecientes a estas familias. Nuestros resultados también demuestran que el tamaño del huevo en langostillas está correlacionado con la profundidad, sugiriendo una estrecha relación entre el hábitat y la duración del desarrollo larval de estas especies.(AU)
Spatial distribution and egg production of squat lobsters is examined from specimens deposited in the collection of the Museu de Zoologia of the Universidade de São Paulo (MZUSP), Brazil. A total of 1,346 specimens of squat lobsters were analyzed, out of which 169 were ovigerous females. Ovigerous females contained ten species of Munididae (n = 165) and three of Munidopsidae (n = 4). Eleven of the thirteen studied species were distributed along the Brazilian coast, while two of the remaining species in other marine regions. The analysis of bathymetric distribution revealed the presence of four species on the continental shelf ( 200 m depth: M. spinifrons, M. pusilla, M. irrasa, M. flinti), two on the first layer of the continental slope (200-500 m: Munida forceps, A. longipes) and five distributed between 500 and 1,048 m (M. erinacea, M. constricta, M. valida, M. microphthalma, M. transtridens). Overall, species belonging to Munididae produced a higher number of eggs (554 ± 619 eggs) but of minor size (0.48 ± 0.120 mm) than species of Munidopsidae (13 ± 10 eggs; 1.12 ± 0.337 mm, respectively). Such tendency is consistent with the phylogeny of both clades whose common origin is reflected in morphological similarities both in larval and adult forms, but not in terms of the reproductive strategy that clearly separates the species belonging to these families. Results also demonstrated that egg size in squat lobsters is strongly associated with depth, which suggests the strong influence of habitat on the duration of larval development of these species.(AU)
Assuntos
Animais , Decápodes/classificação , Distribuição Animal , Oceano Atlântico , Fertilidade , BrasilRESUMO
Se examinó la distribución espacial y la producción de huevos de langostillas depositados en la colección del Museu de Zoologia de la Universidade de São Paulo (MZUSP), Brasil. Para ello, se analizaron 1.346 ejemplares, de los cuales 169 correspondieron a hembras ovígeras. Las hembras ovígeras estuvieron distribuidas en diez especies de Munididae y tres de Munidopsidae. Once de las trece especies estudiadas se distribuyeron en la costa brasilera, mientras que dos en otras regiones marinas. El análisis de la distribución batimétrica reveló la presencia de cuatro especies de langostillas sobre la plataforma continental ( 200 m: M. spinifrons, M. pusilla, M. irrasa, M. flinti), dos en la primera franja del talud continental (200-500 m: Munida forceps, A. longipes) y cinco distribuidas entre 500 y 1048 m de profundidad (M. erinacea, M. constricta, M. valida, M. microphthalma, M. transtridens). En general, las especies de Munididae produjeron una alta cantidad de huevos (554 ± 619 huevos) de pequeño tamaño (0,48 ± 0,120 mm) comparado con las especies de Munidopsidae (13 ± 10 huevos; 1,12 ± 0,337 mm, respectivamente). Esta tendencia es consistente con la filogenia de ambos clados cuyo origen en común se refleja en similitudes morfológicas tanto en las formas larvales como en las adultas, pero no así en la estrategia reproductiva que claramente separa las especies pertenecientes a estas familias. Nuestros resultados también demuestran que el tamaño del huevo en langostillas está correlacionado con la profundidad, sugiriendo una estrecha relación entre el hábitat y la duración del desarrollo larval de estas especies.
Spatial distribution and egg production of squat lobsters is examined from specimens deposited in the collection of the Museu de Zoologia of the Universidade de São Paulo (MZUSP), Brazil. A total of 1,346 specimens of squat lobsters were analyzed, out of which 169 were ovigerous females. Ovigerous females contained ten species of Munididae (n = 165) and three of Munidopsidae (n = 4). Eleven of the thirteen studied species were distributed along the Brazilian coast, while two of the remaining species in other marine regions. The analysis of bathymetric distribution revealed the presence of four species on the continental shelf ( 200 m depth: M. spinifrons, M. pusilla, M. irrasa, M. flinti), two on the first layer of the continental slope (200-500 m: Munida forceps, A. longipes) and five distributed between 500 and 1,048 m (M. erinacea, M. constricta, M. valida, M. microphthalma, M. transtridens). Overall, species belonging to Munididae produced a higher number of eggs (554 ± 619 eggs) but of minor size (0.48 ± 0.120 mm) than species of Munidopsidae (13 ± 10 eggs; 1.12 ± 0.337 mm, respectively). Such tendency is consistent with the phylogeny of both clades whose common origin is reflected in morphological similarities both in larval and adult forms, but not in terms of the reproductive strategy that clearly separates the species belonging to these families. Results also demonstrated that egg size in squat lobsters is strongly associated with depth, which suggests the strong influence of habitat on the duration of larval development of these species.
Assuntos
Animais , Decápodes/classificação , Distribuição Animal , Oceano Atlântico , Brasil , FertilidadeRESUMO
RESUMEN: Se examinó la distribución espacial y la producción de huevos de langostillas depositados en la colección del Museu de Zoologia de la Universidade de São Paulo (MZUSP), Brasil. Para ello, se analizaron 1.346 ejemplares, de los cuales 169 correspondieron a hembras ovígeras. Las hembras ovígeras estuvieron distribuidas en diez especies de Munididae y tres de Munidopsidae. Once de las trece especies estudiadas se distribuyeron en la costa brasilera, mientras que dos en otras regiones marinas. El análisis de la distribución batimétrica reveló la presencia de cuatro especies de langostillas sobre la plataforma continental ( 200 m: M. spinifrons, M. pusilla, M. irrasa, M. flinti), dos en la primera franja del talud continental (200-500 m: Munida forceps, A. longipes) y cinco distribuidas entre 500 y 1048 m de profundidad (M. erinacea, M. constricta, M. valida, M. microphthalma, M. transtridens). En general, las especies de Munididae produjeron una alta cantidad de huevos (554 ± 619 huevos) de pequeño tamaño (0,48 ± 0,120 mm) comparado con las especies de Munidopsidae (13 ± 10 huevos; 1,12 ± 0,337 mm, respectivamente). Esta tendencia es consistente con la filogenia de ambos clados cuyo origen en común se refleja en similitudes morfológicas tanto en las formas larvales como en las adultas, pero no así en la estrategia reproductiva que claramente separa las especies pertenecientes a estas familias. Nuestros resultados también demuestran que el tamaño del huevo en langostillas está correlacionado con la profundidad, sugiriendo una estrecha relación entre el hábitat y la duración del desarrollo larval de estas especies.
ABSTRACT: Spatial distribution and egg production of squat lobsters is examined from specimens deposited in the collection of the Museu de Zoologia of the Universidade de São Paulo (MZUSP), Brazil. A total of 1,346 specimens of squat lobsters were analyzed, out of which 169 were ovigerous females. Ovigerous females contained ten species of Munididae (n = 165) and three of Munidopsidae (n = 4). Eleven of the thirteen studied species were distributed along the Brazilian coast, while two of the remaining species in other marine regions. The analysis of bathymetric distribution revealed the presence of four species on the continental shelf ( 200 m depth: M. spinifrons, M. pusilla, M. irrasa, M. flinti), two on the first layer of the continental slope (200-500 m: Munida forceps, A. longipes) and five distributed between 500 and 1,048 m (M. erinacea, M. constricta, M. valida, M. microphthalma, M. transtridens). Overall, species belonging to Munididae produced a higher number of eggs (554 ± 619 eggs) but of minor size (0.48 ± 0.120 mm) than species of Munidopsidae (13 ± 10 eggs; 1.12 ± 0.337 mm, respectively). Such tendency is consistent with the phylogeny of both clades whose common origin is reflected in morphological similarities both in larval and adult forms, but not in terms of the reproductive strategy that clearly separates the species belonging to these families. Results also demonstrated that egg size in squat lobsters is strongly associated with depth, which suggests the strong influence of habitat on the duration of larval development of these species.
RESUMO
A new callianideid species, Callianidea mariamartae n. sp. is described from the Pacific coast of Costa Rica. The material is compared with the type description of C. laevicauda Gill, 1859 and C. typa H. Milne Edwards, 1837. Diagnostic features of the new species include a linea thalassinica very short, lateral margin of carapace with a distinct hepatic groove, accessory respiratory filaments unsegmented, outer uropodal ramus with strong longitudinal carinae. This is first record of the genus from eastern Pacific of Central America and third report of the family from world. A key for identification of the species belonging to the genus is provided in this document.
Assuntos
Decápodes/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , América Central , Decápodes/anatomia & histologia , Ecossistema , MasculinoRESUMO
Freshwater crabs are an important component of the fauna of limnic environments, and out of the two true freshwater crab families present in the Neotropics, Pseudothelphusidae is the most diverse. Considering the lack of information regarding reproductive features of neotropical freshwater crabs, we studied, for the first time, the fecundity and the presence of juveniles carried by females of two pseudothelphusids from the Amazon region - Kingsleya latifrons (Randall, 1840) and Kingsleya ytupora Magalhães, 1986 - and one from Central America - Potamocarcinus magnus (Rathbun, 1896). The two Kingsleya species produced relatively few (56-114) and large eggs (1.9-3.7 mm), typical for species with an abbreviated or direct development. Recently produced eggs were substantially larger in K. latifrons (mean 2.83 mm) when compared to those of K. ytupora (mean 1.87 mm); however, at the end of the embryogenesis, mean egg diameter was similar in both species. Therefore, it is assumed that hatchlings in both species should have a similar size. A brief description of attached juveniles of K. ytupora is provided. The number of juveniles varied between 30 (K. ytupora) and 179 (P. magnus); two size groups of juveniles were found, which indicates that the offspring cling to their mother for a prolonged period of time. There was no significant loss of eggs and juveniles; it is assumed that parental care diminishes the loss of their offspring. We compiled the available information of reproductive aspects from freshwater crabs: egg diameter was in the range of 2-3 mm, independent of female size and fecundity, and reported egg number varied between 9 and 417 eggs.
RESUMO
Freshwater crabs are an important component of the fauna of limnic environments, and out of the two true freshwater crab families present in the Neotropics, Pseudothelphusidae is the most diverse. Considering the lack of information regarding reproductive features of neotropical freshwater crabs, we studied, for the first time, the fecundity and the presence of juveniles carried by females of two pseudothelphusids from the Amazon region - Kingsleya latifrons (Randall, 1840) and Kingsleya ytupora Magalhães, 1986 - and one from Central America - Potamocarcinus magnus (Rathbun, 1896). The two Kingsleya species produced relatively few (56-114) and large eggs (1.9-3.7 mm), typical for species with an abbreviated or direct development. Recently produced eggs were substantially larger in K. latifrons (mean 2.83 mm) when compared to those of K. ytupora (mean 1.87 mm); however, at the end of the embryogenesis, mean egg diameter was similar in both species. Therefore, it is assumed that hatchlings in both species should have a similar size. A brief description of attached juveniles of K. ytupora is provided. The number of juveniles varied between 30 (K. ytupora) and 179 (P. magnus); two size groups of juveniles were found, which indicates that the offspring cling to their mother for a prolonged period of time. There was no significant loss of eggs and juveniles; it is assumed that parental care diminishes the loss of their offspring. We compiled the available information of reproductive aspects from freshwater crabs: egg diameter was in the range of 2-3 mm, independent of female size and fecundity, and reported egg number varied between 9 and 417 eggs.
RESUMO
La historia natural de los camarones fantasma, conocidos por modelar la estructura de las comunidades en hábitats de aguas someras, ha sido poco estudiada en el Pacífico suramericano. Aquí presentamos información ecológica concerniente a Callichirus seilacheri, con base en individuos recolectados entre enero y diciembre de 2003 en playa Las Machas, norte de Chile. La densidad de las madrigueras varió entre 1.4 y 20.2 madrigueras / 0.25 m2, y fue mayor durante el verano (18.2 madrigueras / 0.25 m2). La proporción de sexos fue 1:1 durante la mayor parte del periodo de estudio; sin embargo, las hembras superaron en número a los machos en enero y setiembre. Los machos presentaron un tamaño máximo mayor al de las hembras (27.1 y 24.0 mm CL, respectivamente). La presencia de juveniles se restringió principalmente al periodo comprendido entre febrero y mayo. La madurez sexual se alcanza a un tamaño de CL de 20.8 mm en los machos y 18.1 mm en las hembras. El periodo reproductivo principal se extendió del otoño al invierno (de mayo a agosto, con un pico en junio), y coincidió con temperaturas decrecientes en el agua y con la presencia de una capa de sedimento sobre las madrigueras.
The life history of ghost shrimps, known for their role in shaping community structures in shallow water habitats, is poorly studied in species occurring along the coasts of the South American Pacific. Here we present ecological information concerning Callichirus seilacheri based upon individuals collected from January to December 2003 in Las Machas beach, northern Chile. Burrow densities varied between 1.4 and 20.2 burrows / 0.25 m2, and was highest during summer (18.2 burrows / 0.25m2). The sex proportion was 1:1 during most of the study period; however, females outnumbered males in January and September. Males reached a larger maximum size than females (27.1 and 24.0 mm CL, respectively). The presence of juveniles was restricted principally to the time between February and May. Sexual maturity was reached at a size of 20.8 mm (males) and 18.1 mm CL (females). The main breeding period lasted from autumn to winter (May to August, peaking in June), and co-occurred with decreasing water temperatures and the presence of a sediment layer covering the burrows.