Species Card of Copepod
Calanoida ( Order )
    Clausocalanoidea ( Superfamily )
        Phaennidae ( Family )
            Onchocalanus ( Genus )
Onchocalanus cristogerens  Markhaseva & Kobosokova, 1998   (M)
Syn.: Onchocalanus cristatus : Harding, 1966
Ref.:
Markhaseva & Kobosokova, 1998 (p.48, Descr.M, figs.M)
Species Onchocalanus cristogerens - Plate 1 of morphological figuresissued from : E.L. Markhaseva & K.N. Kosobokova in Zoosyst. Ross., 1998, 7 (1). [p.49, Figs.22-31].
Male (80°55'N, 122°39'E): 22, anterior part of the body (lateral); 23, forehead (dorsal); 24, rostrum (frontal view); 25, pediger segment 5 and urosome (dorsal); 26, pediger segments 3-5 and urosome (lateral); 27, A2; 28, Md (mandibular palp); 29, Mx1; 30, Mx2; 31, Mxp.
Scale bars: 0.1 mm.

Nota : Prosome nearly 3.8 times as long as urosome. Crest moderately pronounced. Rostrum with thin fimaments terminally. Pediger segments 4 and 5 incompletely fused ; posterior corners of pediger segment 5 rounded in lateral view and triangular in dorsal view. A1 as long as body A2 exopodite 1-2 without seta, exopodite 7 with 3 long terminal setae. Md palp with 2 minute setae at the basis, endopodite 1 with 2 setae, endopodite 2 with 9 setae ; exopodite 1-4 segments with 1 seta each, exopodite 5 with 2 terminal setae. Inner lobe 1 setation reduced, without well developed spines ; inner lobe 2 without setae ; inner lobe 3 with 3 setae ; inner lobe 4 with 4 setae ; endopod with 8 setae ; exopod with 11 setae ; outer lobe 1 with 7 setae. Mx2 lobe 5 with 1 of 3 setae as spine-like ; distal part with 1 worm-like and 6 brush-like setae (probably 7th brush-like seta typical of Phaennidae is broken).


Species Onchocalanus cristogerens - Plate 2 of morphological figuresissued from : E.L. Markhaseva & K.N. Kosobokova in Zoosyst. Ross., 1998, 7 (1). [p.50, Figs.32-37].
Male: 32, P1; 33, P2; 34, P3 (incomplete); 35, P4 (incomplete); 36, P5; 37, right P5 and P5 left first segment.
Scale bars: 0.1 mm.

Nota : P5 uniramous ; left leg 5-segmented, slightly more than 2 times as long as urosome ; right leg 4-segmented, reaching the distal border of the 1st segment of the left leg.

Compl. Ref.:
Kosobokova & Hirche, 2000 (p.2029, tab.2); Kosobokova & Hopcroft, 2010 (p.96, Table 1, fig.7); Kosobokova & al., 2011 (p.29, Table 2, Rem.: Arctic Basins)
NZ: 1

Distribution map of Onchocalanus cristogerens by geographical zones
Loc:
Arctic (Canada Basin, Makarov Basin, Amundsen Basin, Nansen Basin)
N: 4
Lg.:
(779) M: 5,1; {M: 5,10}
Rem.: In vertical haul from Eastern Eurasian Basin: 3566-2000 m.
After Markhaseva & Kosobokova (1998, p.51) the genus Onchocalanus was registered in the Arctic Basin by Harding (1966) and Dunbar & Harding (1968) ; they referred to the species as Onchocalanus cristatus (Wolfenden, 1904), but mentioned : the form recorded in the Arctic Ocean has probably diverged somewhat and should be given a variety or other subspecific status. Comparison with the redescriptions of O. cristatus (Park, 1983 ; Tanaka, 1992) prove their supposal. Markhaseva & Kosobokova consider the Arctic form as a separate species. The shape and the rate of crest development distinguish O. cristogerens from O. cristatus and O. subcristatus.
Last update : 27/01/2015
    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., 2005-2024. - Biodiversity of Marine Planktonic Copepods (morphology, geographical distribution and biological data). Sorbonne University, CNRS. Available at http://copepodes.obs-banyuls.fr/en [Accessed October 06, 2024]

© copyright 2005-2024 Sorbonne University, CNRS

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

 

Version française
English version

 

Search

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