(Murcia: Universidad de Murcia, Servicio de Publicaciones, 2005) Al-Jufaily, S M; A Jawad, Llaith; Al-Azi, A N; Sin departamento asociado; Facultad de Biología
Siamese twins represent a condition in which two
animals are conjoined to varying degrees. The occu
rrence of the phenomenon is well documented in di
fferent vertebrate groups (Witschi, 1952). Jussieu
(1754) reported the first case among fish (Carassius
sp.). It is common in both farmed and wild fish stock
species (Hulata and Rothbard, 1978, Huang et al.,
1987, Roberts, 1989, Bruno, 1990), where in the lat
ter; only few cases survive beyond the absorbed yolk
sac stage (Gordolla, 1968).