Revista Chilena de Historia Natural 76 (2): 205-218, 2003
SIMPOSIUM
Extended parental care in crustaceans – an update
Many crustacean species show extended parental care (XPC) for fully developed juvenile
offspring. Herein, the present state of knowledge of the major patterns and consequences of XPC is reviewed, and furthermore
important future research topics are identified. Crustaceans with XPC are found in marine, freshwater and terrestrial environments, but
care for late juvenile stages appears to be more common in terrestrial environments. In all species, females participate or even take
the main share of XPC activities. Crustaceans that carry their offspring during XPC commonly release early juvenile stages, while
species inhabiting particular microhabitats may host offspring until these have reached subadult or adult stages. Apart from providing a
suitable and safe microhabitat to small offspring, parents share food with, groom or actively defend their juveniles. Some of the most
important benefits of XPC include improved juvenile growth and survival. XPC may also lead to conflicts among developing offspring or
between parents and offspring, especially during later phases of XPC when resources (food and space) become increasingly limiting.
Similarly, during long-lasting cohabitation, epibionts (e.g., parasites) may be transferred from parents to offspring, as is indicated by
observational evidence. For several species, local recruitment, where juveniles recruit in the immediate vicinity of their parents, has
been observed. Under these conditions, local populations may rapidly increase, potentially leading to intraspecific competition for
space, thereby possibly causing a decrease in reproductive activity or a reduction in length of XPC. Another consequence of XPC and
local recruitment could be limited dispersal potential, but some marine crustaceans with XPC and local recruitment nevertheless have
a wide geographic distribution. It is hypothesized that the existence of suitable dispersal vectors such as floating macroalgae or wood
can lead to a substantial increase in dispersal distances of crustaceans with XPC via rafting, surpassing that of crustaceans with
pelagic larvae. Since crustaceans with XPC may be particularly susceptible to changing environmental conditions, especially in the
terrestrial environment where populations are often small and locally restricted, conservation of biodiversity should focus on these (and
other invertebrate) species with XPC.
Key words:
Crustacea, Peracarida,
reproduction, parental care, habitat, evolution
