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An unusual testicular structure in the white grunt, Haemulon plumieri , and the French grunt, H. flavolineatum , and a urinary exocrine gland in H. flavolineatum are described. The testes of both species are comprised predominantly of efferent ducts, with spermatogenetic tissue restricted to the gonadal periphery. The epithelial cells of the efferent ducts produce glycogen which may serve a role in the storage and nutrition of sperm. The urinary gland is a male accessory gland thought to be associated with reproduction. The gland is mesonephric in origin and the epithelial cells of the gland produce mucins which may be involved in intraspecific chemical communication.  相似文献   
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Threeline grunt (Parapristipoma trilineatum) distributes around the southwestern coast of Japan and the east coast of China. The Chinese P. trilineatum was imported by Japan as an aquacultural seed because of its rapid growth compared with that of the Japanese P. trilineatum. The Japanese P. trilineatum differs from the Chinese P. trilineatum in some quantitative traits, and it has been suggested that these two P. trilineatum populations are genetically different. In order to identify the population structures around Japan and China, 5 local populations of the Japanese P. trilineatum and 2 local populations of the Chinese P. trilineatum were analyzed using 4 microsatellite DNA markers. Significant differences were detected between Japanese and Chinese P. trilineatum and among samples of Chinese P. trilineatum; however, among the samples of Japanese P. trilineatum, no significant differences were detected. These results suggest that care must be taken to prevent the escape of the Chinese P. trilineatum from culture cages around the Japanese coast, in order to preserve the genetically different population structures of Japanese and Chinese P. trilineatum.  相似文献   
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The reproductive biology of the white grunt Haemulon plumierii was studied from 360 individuals obtained from artisanal fisheries landings in the Abrolhos Bank, Brazil, between August 2010 and March 2012. The overall sex‐ratio did not differ significantly from 1:1, although males predominated in larger size classes. β‐Binomial modelling of historical sex‐ratio data indicated that the catch rate of females has increased in recent years. Females reached maturity at a smaller total length (LT; 214 mm) than males (235 mm LT) and the LT at which 50% of all individuals are mature (L50) was 220 mm, corresponding to 41·5% of the maximum recorded LT. Variation in the gonado‐somatic index and in the relative frequency of reproductive stages indicates that reproduction occurs year round, with increased activity during the austral spring and summer. Fecundity was not size dependent. The reproductive parameters provided here can support management measures focussed on seasonal closures during spawning peaks (September to November and February to March) and minimum sizes (>L50) for the capture of this important artisanal fisheries resource in Abrolhos, the region with the largest and most biodiverse coralline reefs in the South Atlantic Ocean.  相似文献   
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Morphometric measurements, meristic counts and DNA barcoding identified the presence of a biglip grunt Plectorhinchus macrolepis in the western Atlantic Ocean. As the species is endemic to the tropical eastern Atlantic Ocean and has not previously been reported in the western Atlantic Ocean, we discuss the possible means by which it might have dispersed to the western Atlantic Ocean. Even though this species is not considered established in Paranaguá Bay, we advocate monitoring of possible new individuals and other exotic fish species.  相似文献   
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The ring‐tailed lemur (Lemur catta) is a group‐living strepsirhine primate endemic to Madagascar that has a complex vocal repertoire including affiliative moan and hmm calls. Past research has suggested that both vocalisations may be contact calls, and we assessed their usage in addition to examining the effect of individual differences and social factors on male calling behaviour. We tested three hypotheses: the group cohesion, preferred companion and individual differences hypotheses. From March to July 2010, 565 h of focal animal data were collected on 31 males aged ≥1 year at the Beza Mahafaly Special Reserve, Madagascar. Focal males were observed for 30 min, with vocalisations, allogrooming and agonistic interactions noted using one‐zero sampling, and general behaviour, nearest neighbour identity and distance noted using instantaneous point sampling, all at 2.5 min intervals. We found support for the group cohesion hypothesis for both vocalisations, and support for the preferred companion and individual differences hypotheses for the hmm but not the moan vocalisation. Moan and hmm calls maintained the distance between a male and his nearest neighbour, and were made at higher rates during behaviours which may lead to separation from conspecifics, such as travel and vigilance. Males made hmm calls at higher rates when they were low‐ranking, and/or when the nearest neighbour of a male or a preferred companion of either sex. Low‐ranking males may hmm call to maintain proximity to specific individuals within social groups who will show them increased tolerance, with the hmm signalling peaceful intent. Ring‐tailed lemurs are one of the best living models of gregarious primate ancestors, and gaining a better knowledge of the function and range of usage of their contact calls informs our understanding of the evolution of primate cognition.  相似文献   
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