6 - Sphaeromatidae::“Cute As Buttons”

FLABELLIFERA • AEGIDAE 115
4. Pereopods 4—7 prehensile, with dactyli longer than propodi; antennae
reduced, with no clear distinction between peduncle and flagellum
Cymothoidae
Pereopods 4—7 ambulatory, with dactyli shorter than propodi; antennae
normal, peduncle and flagellum clearly distinguished 5
5. Maxilliped bearing distal recurved hooks; pereopods 1-3 strongly
prehensile Aegidae
Maxilliped lacking distal recurved hooks; pereopods 1-3 ambulatory or
at most weakly prehensile 6
6. Maxilliped lacking, or with very reduced endite; maxilla 1 a strongly
falcate hook Corallanidae
Maxilliped with strong endite; maxilla 1 not strongly falcate 7
7. Mandibular incisor distally narrowed, lacinia lacking; maxilla 1 slender
and elongate, with 3-5 distal hooked spines Tridentellidae **
Mandibular incisor distally broad, cusped; maxilla 1 relatively broad,
with several distal spines and setae Cirolanidae {
usually consisting of two lobes. Pereopods generally ambulatory, sometimes
prehensile; pereopods 1 and 2 subchelate only in Serolidae, ancinine
Sphaeromatidae, and some Cirolanidae; posterior pereopods sometimes sec­
ondarily natatory in some cirolanids. Pleon consisting of as many as five free
pleonites plus pleotelson, but pleonites variously fused in several families.
Five pairs of pleopods usually present, Uropods lateral, usually forming tail-
fan with pleotelson.
REMARKS This suborder contains a large group of diverse families, largely
held together by primitive features such as the tailfan structure. Future work
will undoubtedly show the Flabellifera to be an artificial polyphyletic group.
Family Aegidae Leach, 1815
DIAGNOSIS Dorsal integument usually unornamented. Coxae distinct on
pereonites 2-7. Eyes usually present, large, often almost, or complete con­
tiguous. Mandible lacking lacinia mobilis, spine-row, and molar. Maxilla 1
slender, with apical spines. Maxilla 2 with two terminal unequal lobes bear­
ing apical spines. Maxillipedal palp of two, three, or five articles. Pereopods
1—3 prehensile, with dactyli strongly curved; pereopods 4—7 ambulatory.