Premium
Abnormal craniofacial development in cyclopic salmonid fishes
Author(s) -
Bolker Jessica A.,
Thomson Keith S.
Publication year - 1992
Publication title -
journal of morphology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.652
H-Index - 74
eISSN - 1097-4687
pISSN - 0362-2525
DOI - 10.1002/jmor.1052110104
Subject(s) - cyclopia , anatomy , biology , craniofacial , dorsum , holoprosencephaly , fetus , pregnancy , genetics
Different types and degrees of “spontaneous” and artificially induced cyclopic malformation in fishes are defined. Symmetrical cyclopia ranges from approximation of the eyes, to partial merger of the eyes in the midline, to complete cyclopia with a single median eye. It is always associated with dorsal displacement of the rostral‐nasal apparatus to the top of the head. Skeletal reorganization associated with symmetrical cyclopia is described for the first time, using hatchery material of Salmo gairdneri and S. trutta . Development of the nasal capsule is essentially normal, except for position; the trabeculae cranii remain in the normal position but show modified shape corresponding to the degree of cyclopia. The jaw apparatus is modified through anterior foreshortening, especially the upper jaws. The branchial apparatus is unaffected. The condition demonstrates that later morphogenesis of the nasal capsule and trabeculae cranii are independent of each other. Cyclopia appears to result from alteration of relative position and timing in developmental events in the head, especially the prosencephalon.