Cymodoce Leach 1814

"'The difficulties connected with the definition of this and various other genera of the Sphaeromidae are discussed by Mr Beddard in his Challenger Isopoda, Reports, Vol. 17, p. 145. Until a monograph of the family is carried out by some patient and skilful hand these difficulties are likely to remain. The incapacity of the animal to become completely globular, the resistance to complete folding of one plate over the other in the uropods, and the presence of a lobe in the excavated apex of the telson, are superficial characters which do not offer very firm ground for generic distinction. The maxillipeds do not differ from those found in Exosphaeroma gigas, and in most of the species which I have assigned to that genus." (Stebbing, 1904)

"The head broad, the first segment of the peraeon the longest, the sides of the body very hirsute, and the hind margins of the segments hairy, the sixth and seventh also tuberculose. In the pleon a small first segment is covered by the peraeon, the composite segment which follows has on the hind margin two sub-median bosses. These are followed on the telsonic segment by two slightly divergent carinae leading to two very large bosses each carrying a crest of hairs. To them succeeds a large median boss. This is followed by a convex-sided apically truncate process emerging beyond the convergent apices of the telsonic emargination. All these parts are strongly fringed with setae, and distinguish the species from C. pilosa, Milne-Edwards, which has an otherwise similar pleon, but ending in an almost cylindrical median plate, rounded at the end and not reaching beyond the two lateral apices. In C. aculeata, Haswell, the median plate projects beyond the lateral points, but it is differently shaped, and the bosses on the pleon are arranged transversely, not in successive paii's. In C. tuberculata, Haswell, the bosses are successive, but of quite different character, and the apices of the terminal notch project beyond the median process.

The eyes are wide apart, the anterior margin of the first pei'aeon-segment being deeply emarginate to receive them.

The first antennae have a large, bent, composite basal joint, with the following joint not very large. To the stoutly constructed peduncle succeeds a slender flagellum of 14 joints, of which the first is much the longest. In the second antennae the peduncle is not robust, the fifth joint a little longer than the fourth, the flagellum 17-jointed. In the mandibles the principal cutting edge is horny-looking, not dentate. The palp is rather slight. The maxillipeds have the fourth, fifth and sixth joints fully lobed. As will be seen in the figure the palp on one side of the specimen was in process of regeneration. The limbs of the peraeon are of the character usual in this family. The male appendages of the seventh peraeon-segment are rather long, not very acute. In the second pleopods the male appendage is very long, with its narrow inward-curving apical part reaching much beyond the plate to which it is attached.

The uropods are straight, rather narrow, very setose, the outer ramus more obliquely truncate than the inner, which it outreaches, both extending beyond the telsonic segment, the outer having a prominent spine at the apex of its raised outer border. In C. Iongistylis, Miers, the inner ramus has an outward curve, and decidedly outreaches the outer. " (Stebbing, 1904)

"Minikoi, from 5 to 7 fathoms in centre of lagoon." (Stebbing, 1904)

"6 mm., breadth, 3 mm." (Stebbing, 1904)

Cymodoce es un género de crustáceo isópodo marino de la familia Sphaeromatidae.

Cymodoce is een geslacht van pissebedden uit de familie Sphaeromatidae. De wetenschappelijke naam van het geslacht werd voor het eerst gepubliceerd door William Elford Leach in 1814 in deel 7 van de Edinburgh Encyclopaedia. Hij beschreef daar ook (zij het zeer bondig) de soort Cymodoce truncata die aan de kust van Devon voorkwam.

Leach beschreef in 1818 ook een geslacht Cymodocea, maar die naam was al in gebruik voor een plantengeslacht. Leach's Cymodocea wordt nu beschouwd als een synoniem van Cymodoce.

In 2013 publiceerden Khalaji-Pirbalouty, Bruce en Wägele een nieuwe beschrijving van het geslacht en van de typesoort C. truncata.

Met een 70-tal soorten is dit het grootste geslacht in de familie Sphaeromatidae. Ze komen over de hele wereld voor, behalve in de poolwateren.