head

See: cephalon [Martin, 2005].

(Order Cladocera):

Anterior of two divisions (tagmata) of body (head, trunk); Consists of five somites bearing antennules, antennae, mandibles, maxillules, and (reduced) maxillae. Bears compound and naupliar eyes and may be covered by a head shield. Not enclosed by carapace. (Clearly delimited/not clearly delimited; helmeted, rounded, with/without rostrum). (Syn. cephalon) [Stachowitsch, 1992].

(Order Notostraca):

Anterior of three divisions (tagmata) of body (head, thorax, abdomen). Consists of five somites bearing in part poorly developed antennules, antennae, mandibles, maxillules, and maxillae. Covered, along with thorax, by carapace; border between head and thorax indicated by cervical groove [Stachowitsch, 1992].

(Order Diplostraca):

Anterior of two divisions (tagmata) of body (head, trunk). Consists of five somites bearing antennules, antennae, mandibles, maxillules, and maxillae. Bears ventral rostrum, compound and nauplius eyes, and is typically entirely enclosed by carapace. (entirely/not entirely enclosed by carapace; with/without frontal appendage). (Syn. cephalon) [Stachowitsch, 1992].

(Order Anostraca):

Anterior of three divisions (tagmata) of bosy (head, thorax, abdomen). Consists of five somites bearing antennules, antennae, mandibles, maxillules, and maxillae. Also bears pair of compound eyes laterally and nauplius eye middorsally; superfically subdivided dorsally by transverse mandibular groove. (Syn. cephalon) [Stachowitsch, 1992].

(Class Cephalocarida):

Cephalon [Stachowitsch, 1992].

(Order Cumacea):

Cephalon [Stachowitsch, 1992].

(Order Tanaidacea):

Anterior of three basic divisions (tagmata) of body (head, thorax, abdomen). Consists of five somites with five pairs of appendages (antennules, antennae, mandibles, maxillules, maxillae); fused with first thoracic somite (bearing maxillipeds), this entire complex also being termed head [Stachowitsch, 1992].

(Order Decapoda):

Cephalon [Stachowitsch, 1992].

(Order Amphipoda):

Cephalon [Stachowitsch, 1992].

(Order Isopoda):

Cephalon [Stachowitsch, 1992].

(Order Mysida):

Anterior of three basic divisions (tagmata) of body (head, thorax, abdomen). Fused with anterior thoracic segments (thoracomeres) to form cephalothorax; covered by carapace [Stachowitsch, 1992].

(Order Stomatopoda):

Cephalon [Stachowitsch, 1992].

(Order Leptostraca):

Cephalon [Stachowitsch, 1992].

(Subclass Branchiura):

Cephalon [Stachowitsch, 1992].

(Subclass Cirripedia):

Anterior of typically two basic divisions (tagmata) of body (head, thorax; in ascothoracican: head, thorax, abdomen). If fully consists of five fused segments (somites) bearing antennules, antennae, mandibles, maxillules, and maxillae [Stachowitsch, 1992].

(Subclass Mystacocarida):

Cephalon [Stachowitsch, 1992].

(Class Ostracoda):

Anterior of two major regions (head, thorax) of body; unsegmented and not clearly delimited from thorax. Bears five pairs of appendages (cephalic appendages), including antennules, antennae, mandibles, maxillules, and maxillae as well as eye. Entirely enclosed in carapace. (Syn. cephalon) [Stachowitsch, 1992].

(Class Remipedia):

Cephalon [Stachowitsch, 1992].

(Superorder Syncarida):

Anterior of three major divisions (tagmata) of body (head, thorax, abdomen). Consists of basically five somites (bearing antennules, antennae, mandibles, maxillules, and maxillae), although in anaspidacean and stygocaridacean first thoracic somite (bearing maxillipeds) is fused to head. (See also cervical groove, rostrum). (Syn. cephalon) [Stachowitsch, 1992].

(Order Thermosbaenacea):

Cephalon [Stachowitsch, 1992].

(Order Euphausiacea):

Cephalon [Stachowitsch, 1992].