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Techniques for Investigating the Anatomy of the Ant Visual System
Published on: November 27, 2017
A crab with three eyes, two rostra, and a dorsal antenna-like structure
Gerhard Scholtz1, Peter K L Ng2, Stephen Moore3
1Humboldt-Universität zu Berlin, Institut für Biologie/Vergleichende Zoologie, Philippstrasse 13, D-10115 Berlin, Germany.
Abstract:
We describe a malformed specimen of the freshwater crab Amarinus lacustris from New Zealand. With three eyes in a horizontal row, two rostra, and a dorsal antenna-like structure, the pattern of malformation of this animal is unique and has not been described before. A careful inspection and description of external and internal structures, in particular the central nervous system, were carried out. These revealed, in addition to the external abnormalities, a retarded brain with a hypertrophied and backwards bent protocerebrum connected with all three eyes and putatively with the dorsal antenna-like structure. Based on these data, a variety of hypotheses about the causes for this kind of malformation are discussed. A scenario combining a conjoined twin (Duplicitas anterior) based on the duplication of the embryonic anterior head lobes and a regeneration event leading to the replacement of an eye by an antenna shows the best fit to the observed patterns.
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