Definitions

(Taxon-specific: Subclass Copepoda) One of up to four stages in copepodid phase of development of caligid-like parasitic copepods; the chalimus usually is attached to the host, often by a frontal filament held by maxilla 2. The first chalimus is molted from the first copepodid stage; the four chalimus stages correspond to the second to fifth copepodid stages. [Ferrari and Dahms, in press]
(Taxon-specific: Subclass Copepoda) The post-copepodid developmental stage of most siphonostomatoid fish parasites, characterised by possession of a frontal filament for attachment to the host. [Boxshall and Halsey, 2004]