From 25 populations of Pseudorasbora in Japan, polymorphism at 22 allozyme loci indicated that the level of genetic differentiation between Pseudorasbora parva and Pseudorasbora pumila (D = 0·421–0·517) was greater than that between the two subspecies of P. pumila, P. pumila pumila and P. pumila subsp. (D = 0·164), consistent with morphological differences. While P. parva displayed genetic variation (H = 0·003–0·100) similar to other freshwater fishes, P. pumila pumila and P. pumila subsp. populations showed no genetic variation. In five of the 15 populations collected from the contact zone between P. parva and P. pumila pumila, hybrids were detected by allozyme analyses. All hybrids were presumed to represent the F1 generation, because they were heterozygous at all 12 loci diagnostic between P. parva and P. pumila pumila. Although four populations were characterized by high frequencies of F1 hybrids (c. 40%), only one of the parental species was observed in each case. The results indicated that the two species have hybridized easily under natural conditions, but cannot coexist in the long‐term. It is suggested that continued invasion of P. parva would hasten the extinction of P. pumila pumila.
Journal of Fish Biology – Wiley
Published: Jul 1, 2003
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera