Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Electronic Resource  (2)
  • Perna viridis  (1)
  • food segregation  (1)
Material
  • Electronic Resource  (2)
Years
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Hydrobiologia 362 (1997), S. 107-113 
    ISSN: 1573-5117
    Keywords: diet ; food segregation ; inter-specific competition ; portunidcrabs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Gastric mills of 2,619 specimens of portunid crabs(Portunus pelagicus, P. sanguinolentus andCharybdis feriatus) in Tolo Harbour, Hong Kongwere examined. Of these, 1,498 containedrecognizable food items. A total of 34 food items wereidentified, 10 of which (29.4%) were common to thethree crab species. The principal food items werebivalves, decapods, fish and algae. However, thepercent frequency of occurrence of these food itemsdiffered significantly (ANOVA, p 〈 0.001) among thecrabs. In addition to these principalfood items, differences were noted in other dietarycategories: P. pelagicusand P. sanguinolentus fed on the brittle starOphiura kinbergi, whereas P.sanguinolentus and C. feriatus fed on detritusand gastropods. The diet of P. sanguinolentuswas found to be more similar to C. feriatus thanto P. pelagicus. Exploitation of different fooditems and selective feeding on common prey may reduceinter-specific competition for natural food resourcesand allow the three portunid crabs to co-exist in thesame habitat.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1438-3888
    Keywords: Key words Spermatogenesis ; Perna viridis ; Acrosome formation ; Flagellum development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Spermatogenesis in the mussel Perna viridis was studied by electron microscopy. Results demonstrated that cytological development in spermatogonia and spermatocytes was similar to that previously described in other Mytilidae. Acrosome formation began with the arising of proacrosomal vesicles in spermatogonia. The abundance of proacrosomal vesicles increased in spermatocytes, which were flagellated. However, during spermiogenesis, dual patterns of acrosome development as well as flagellum development could be found among spermatids in a male gonad. The two lines of acrosome formation in spermatids ultimately gave rise to morphologically similar acrosomes. The two lines of flagellum development in spermatids resulted in the formation of sperm cells with either a typically posteriorly directed tail or an anteriorly directed tail.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...