Abstract
Studies in the northern (Rio San Juan) watershed in Costa Rica show that the freshwater crab Potamocarcinus nicaraguensis has spread from its original habitat in the Great Lakes region of Nicaragua throughout the Rio San Carlos basin into rivers and streams having clear water, a muddypebbly bottom and temperatures above 20 C. Some intraspecific adaptive variation is apparent as to length and width of the carapace and coloration, the San Carlos crabs being darker than those from the Nicaraguan lake region. No other major diferences were found between the two populations, which have not as yet become entirely separated from each other.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
