Species Card of Copepod
Calanoida ( Order )
    Clausocalanoidea ( Superfamily )
        Phaennidae ( Family )
            Xanthocalanus ( Genus )
Xanthocalanus irritans  (Tanaka, 1960)   (M)
Syn.: Amallophora irritans Tanaka, 1960 a (p.113, Descr.M, figs.M)
Bradford & al., 1983 (p.71); Tanaka & Omori, 1992 (p.270, Rem.)
Species Xanthocalanus irritans - Plate 1 of morphological figuresissued from : O. Tanaka in Publ. Sero Mar. Biol. Lab., 1960, VIII (1). [p.113, Fig.94]. As Amallophora irritans.
Male (from Sagami Bay, Japan): a, habitus (dorsal); b, forehead (lateral); c, last thoracic segment with P5 and urosome (lateral left side); d, Mx1; e, Mx2; f, Mxp; g, P1; h, P2; i, right P5; j, distal joint of left P5.

Nota: Head and 1st thoracic segment separate, 4th and 5th incompletely separate.
Rostrum bifurcate, attenuates into 2 slender filaments.
A2 exopodite about 1.2 times as long as the endopodite (36 : 29); tje posterior surface of the 1st basal segment furnished with rows of long curled hairs.
Mx1 with 10 setae on the exopodite, 5+3 setae on the endopodite, 5 setae on the 2nd basal, 4 setae on the 3rd inner lobe; the 1st and 2nd inner lobes are much reduced.
Mx2 with a single large sensory appendage on the endopodite; the setae on the lobes are much reduced.
Mxp with a small sensory appebdage on the anterior proximal margin of the 1st basal segment; the 2nd basal segment thick.
The abdominal segments and furca in the proportions 14 : 30 : 23 : 20 : 3 : 10 = 100.
P5 5-segmented. Right P5 short, the distal joint has an apical spine and short hairs on the outer margin, 3rd and 4th joints fused (each carries short hairs on the outer margin); left P5 exceeding the distal margin of the abdomen, the distal joint with 2 apical spines, of which the outer one is very minute, and a small spine on the distal 1/3 of the outer margin, the 4th joint has a slender spine on the inner distal angle.

Species Xanthocalanus irritans - Plate 2 of morphological figuresissued from : O. Tanaka in Publ. Sero Mar. Biol. Lab., 1960, VIII (1). [p. 114]. As Amallophora irritans.
Male: Proportional lengths of segments of A1.

Nota: A1 23-segmented, extends about to the distal end of thoracic segment; the distal 3 segments are broken off.

NZ: 1

Distribution map of Xanthocalanus irritans by geographical zones
Japan (Sagami Bay)
N: 1
(4) M: 2,43; {M: 2,43}
Rem.: Sampling between 0-1000 m.
Last update : 02/02/2015
    to add your remark

 Any use of this site for a publication will be mentioned with the following reference :

Razouls C., Desreumaux N., Kouwenberg J. and de Bovée F., 2005-2023. - Biodiversity of Marine Planktonic Copepods (morphology, geographical distribution and biological data). Sorbonne University, CNRS. Available at http://copepodes.obs-banyuls.fr/en [Accessed November 29, 2023]

© copyright 2005-2023 Sorbonne University, CNRS

CNRS   Observatoire Océanologique de Banyuls sur Mer - Laboratoire Arago
Sorbonne Université


Version française
English version



On the WEB of CNRS


Marine Planktonic Copepods

Marine Planktonic Copepods


Imprimer Contact Accueil Plan du site Accès restreint Retour Une du Labo Imprimer Contact Plan du site Crédits Téléchargez les Plug-Ins