共查询到20条相似文献,搜索用时 0 毫秒
1.
The present state of knowledge concerning Portunus larvae isreviewed, and the three zoeal and the megalopa stages of P.rubromarginatus are described and figured. Details of appendagesetation are tabulated. This species is unusual amongst knownPortunus spp. in having only three zoeal stages and, like otherPortunus spp. but in contrast with other Portuninae, it has4 + 4, or 4 + 1 + 4, setae on the posterior telson border. When compared with larvae of the five other Indo-West PacificPortunus species whose larvae are known P. rubromarginatus zoeaeare readily distinguished from all, except P. hastatoides, usingthe key features given by Kurata (1975). Comparison was madebetween first zoeae of these two species, and also of P. pelagicusand P. sanguinolentus, using larvae reared by the authors. Itwas found telson characters alone allow distinction betweenlarvae of these four species. These characters are tabulated. P. rubromarginatus megalopae differ from those known for congenitorsin having a large spine on the uchium of the first pereiopod,but not on the carpus, and in having relatively very small sternalcornuae. Several of these features disagree with those previously thoughtto characterise larval Portuninae or Portunus species. 相似文献
2.
The complete larval development of the Eastern Atlantic grapsidcrab, Brachynotus atlanticus, was obtained in the laboratory.Five zoeal stages, the megalopa and the first crab stage aredescribed and illustrated. Under laboratory conditions at 23°Cthe first crab appeared on the 25th day. This is the first speciesof the genus for which the complete larval development is known.Larval features are compared with those of other members ofthe subfamily Varuninae. 相似文献
3.
Seong Mi Oh 《Invertebrate reproduction & development.》2013,57(3):220-228
The spider crab Platymaia wyvillethomsoni was reared in the laboratory, from hatching to the megalopal stage at 20°C. The larval development comprises two zoeal stages and a megalopa. The zoeal stages are described for the first time and compared with those of the four known species of the family Inachidae from the northern Pacific. The zoeal characters (carapace spines, antenna, mouthpart appendages, pleon and telson fork) of P. wyvillethomsoni are significantly different from those of two Achaeus species from northern Pacific and other inachid genera (Inachus and Macropodia) from the Atlantic. Therefore, this species should not be placed in the family Inachidae based on zoeal morphology. A provisional key for the identification of known zoeae of the family from the northern Pacific is provided. 相似文献
4.
5.
6.
7.
8.
9.
10.
The early stages of the Panulirus echinatus were hatched and reared in the laboratory. Ovigerous females were captured in their habitat and carefully transported to the laboratory. Larvae were transferred in a recirculation water tank at a density of 10 larvae.L(-1). The larvae were fed on Artemia and gonads of mussel Brachydonts sp. Microalgae Dunaliella viridis was added at a concentration of 150 x 10(4) cell.mL(-1). Larvae and exuviae of each zoeal stage were preserved in an alcohol 70% + glycerin (1:1) solution. The phyllosomas moulted eight times; the intermoulting period of each instar averaged about 7 to 10 days. The main morphological changes of each appendage were described in detail, illustrated and compared with previous reports. 相似文献
11.
The estuarine grapsid crabs Chasmagnathus granulata and Cyrtograpsus angulatus belong to the most typical and dominant inhabitants of brackish coastal lagoons in southeastern South America. In a combined
laboratory and field investigation of juvenile growth, we measured the increase in body size in these species under controlled
conditions as well as in field experiments (in Mar Chiquita lagoon, Argentina), seasonal changes in size frequency distribution
of a natural population, and growth related changes in selected morphometric traits of male and female juveniles (relations
between carapace width, carapace length, propodus height and length of the cheliped, and pleon width). At 24°C, Cy. angulatus grew faster than Ch. granulata; it reached the crab-9 instar (C9; 13 mm carapace width) after 92 days, while Ch. granulata required 107 days to reach the C8 instar (7.4 mm). At 12°C, growth ceased in both species. The pleon begins to show sexual
differences in the C5 (Cy. angulatus) and C8 instar (Ch. granulata), respectively, while the chelae differentiate earlier in Ch. granulata than in Cy. angulatus (in C4 vs C6). In the field, growth was maximal in summer, and was generally faster than in laboratory cultures. However,
there is great individual variability in size (about 25% even in the first crab instar) and in size increments at ecdysis,
increasing throughout juvenile growth. Our data indicate that, in the field, small-scale and short-term variations in feeding
conditions, temperature, and salinity account for an extremely high degree of variability in the absolute and relative rates
of growth as well as in the time to sexual differentiation.
Received in revised form: 20 September 2001
Electronic Publication 相似文献
12.
13.
The genus Hexapanopeus Rathbun, 1898 contains eight species,of which three are found in the Brazilian coast. The larvaldevelopment of two of these species has already been studiedin the laboratory. This article describes in detail the morphologyof the complete larval stages of Hexapanopeus caribbaeus rearedunder laboratory conditions, and the morphology is comparedwith that of the larvae of the other species of the same genus. 相似文献
14.
The Grapsidae and Ocypodidae (Decapoda: Brachyura) of Tanzania 总被引:3,自引:0,他引:3
R. G. Hartnoll 《Journal of Zoology》1975,177(3):305-328
Twenty-nine species of the Grapsidae and 15 species of the Ocypodidae were collected from the littoral zone in the area around Dar es Salaam. Nine species of Grapsidae and three of Ocypodidae were new records for the East African area, bringing the total of recorded species for the region to 35 and 26 respectively. The distribution of these crabs indicates a very limited endemism in the western Indian Ocean, with the majority of species forming an attenuated extension of the abundant Indo/West Pacific brachyuran fauna.
The habitat preference of each species is described. Within each subfamily there is a relative uniformity in general habitat preference, mode of life and manner of feeding. The species of each subfamily are then separated by substrate choice and preferred level on the shore. The greatest numbers of species occur in the most diverse habitats—the creek mangrove, the coastal mangrove and the reef flat. 相似文献
The habitat preference of each species is described. Within each subfamily there is a relative uniformity in general habitat preference, mode of life and manner of feeding. The species of each subfamily are then separated by substrate choice and preferred level on the shore. The greatest numbers of species occur in the most diverse habitats—the creek mangrove, the coastal mangrove and the reef flat. 相似文献
15.
16.
17.
The megalopae and first crab instars are described for three of the four Indo-west Pacific species of the grapsid crab Percnon—P. abbreviatum, P. guinotae and P. planissimum . Keys are provided to these three species and for the Atlantic/East Pacific P. gibbesi . The validity of separating P. planissimum and P. gibbesi is discussed, as are the implications of the unusually large megalopa in Percnon . 相似文献
18.
The first three zoeal stages of the portunid crab Macropipus
tuberculatus (Roux, 1830) are described and illustrated from
laboratory-reared material obtained from one ovigerous crab captured in the
western Mediterranean Sea. Zoeae of M.tuberculatus can
be distinguished from other known polybiinid species from the northeastern
Atlantic and Mediterranean waters by a combination of meristic and
morphometric features, especially by the number of setae in the outer lobe
of the maxilla endopod. Larval morphology presents additional evidence
supporting the split of the genus Macropipus into the
genera Liocarcinus and Macropipus sensu
stricto based on adult characters.
相似文献
19.
20.
Complete larval development of Crangon hakodatei Rathbun isdescribed, based on material hatched in the laboratory fromovigerous females. The species has six zoeal stages and onepostlarval stage. The morphological characters of the larvaland postlarval stages are described with illustrative figuresand compared with those of two congeneric species. The zoealstages of C. hakodatei can be distinguished from those of otherCrangon species in the number of segments of the antennule peduncle,the number of setae on the antennal scale and basis of the maxillipeds,and the stages of appearance of pereiopods. The first zoealstage in the seven species of Crangon are compared and an annotatedkey for distinguishing them is also provided. 相似文献