Species Card of Copepod
Calanoida ( Order )
    Arietelloidea ( Superfamily )
        Arietellidae ( Family )
            Arietellus ( Genus )
Arietellus unisetosus  Guangshan & Honglin, 1997   (F)
Syn.: Arietellus giesbrechti : Tanaka, 1964 c (p.231, figs.F);
no Arietellus sp. Ohtsuka & al., 1994 (p.131, figs.F)
Ref.:
Guangshan & Honglin, 1997 (p.396, Descr.F, figs.F, Table 1, Rem.)
Species Arietellus unisetosus - Plate 1 of morphological figuresissued from : L. Guangshan & Q. Honglin in Acta Oceanologica Sinica, 16 (3). [p.397, Fig.1].
Female (from equatorial Pacif.: 2°30'N - 7°S, 170°09'W - 171°30'E): 1, habitus (dorsal); 2, forehead (lateral); 3, last thoracic segment and urosome (lateral left side); 4, idem (ventral); 5, right A1 (dorsal); 6, left A2; 7, left Md (masticatory edge); 8, left Mx1; 9, basal spine of Mx2; 10, 1st to 6th endopod segments of left Mxp; 11, right P1 (anterior) ; 12, right P2 (posterior); 13, right P3 (posterior); 14, right P4 (posterior); 15, P5 (posterior).

Nota: Head and 1st thoracic segments eparate, 4th and 5th fused.
Forehead (dorsal view): obtusely triangular.
Rostrum with 2 slender filaments.
A1 20-segmented, extending to the end of the anal segment.
Caudal rami asymmetrical, left ramus broader, outer margin swollen, knob-like.
P5: outer marginal seta of basipod 2 of left leg longer, remarkably beyond the end of exopod.


Species Arietellus unisetosus - Plate 2 of morphological figuresIssued from : O. Tanaka in Publ. Seto Mar. Biol. Lab., 1964, XII (3). [p; 32, Fig.220]. As Arietellus giesbrechti.
Female (from Sagami Bay, Japan): a, habitus (dorsal); b, forehead (lateral); c-d, last thoracic segment and abdomen (ventral and lateral, respectively); e, A2; f, P1; g, P2; h, P5.

Nota: Head and 1st thoracic segment separate, 4th and 5th fused.
Last thoracic segment produced on each side into acute expansion, but asymmetrical, left side more produced than the right.
Rostral filaments slender.
Abdomen 4-segmented; segments and caudal rami in the proportional lengths 30 : 13 : 8 : 17 : 32 = 100.
Genital segment contracts near the distal lateral margin; genital opening produced below near the proximal.
Caudal rami asymmetrical, right ramus slightly wider than the left.
Cephalothorax 4.06 mm; abdomen 1.06 mm.
A2 exopod much shorter than the endopod (29 : 45).
P5 asymmetrical; left leg larger than the right; 2nd basal segment 1-segmented, with no strong spine on the distal margin.

Remarks: The present specimen agrees with the description and figures of A. giesbrechti given by Sars, but appears to be an abnormal example of this latter species.


Species Arietellus unisetosus - Plate 3 of morphological figuresIssued from : O. Tanaka in Publ. Seto Mar. Biol. Lab., 1964, XII (3). [p; 32, Fig.220]. As Arietellus giesbrechti.
Female : Proportional lengths of segments of A1.

Nota: A1 20-segmented, extends to the distal margin of the cephalothorax.


Species Arietellus unisetosus - Plate 4 of morphological figuresissued from : L. Guangshan & Q. Honglin in Acta Oceanologica Sinica, 16 (3). [p.399, Table 1].
Female : morphological characters in Arietellus unisetosus.

Nota: Compare with A mohri and A. giesbrechti.

NZ: 3

Distribution map of Arietellus unisetosus by geographical zones
Loc:
W Pacif. (equatorial), Japan (Sagami Bay), Canary Is.

Type species: 7°00' S, 171°30' E.
N: 3
Lg.:
(120) F: 5,12; (262) F: 4,63-4,5; (263) F: 5,15; {F: 4,50-5,15}
Rem.: Heinrich (1996) and Guangshan & Honglin (1997) do not agree on the synonymies.
Last update : 22/10/2015
    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., 2005-2021. - Biodiversity of Marine Planktonic Copepods (morphology, geographical distribution and biological data). Sorbonne University, CNRS. Available at http://copepodes.obs-banyuls.fr/en [Accessed September 24, 2021]

© copyright 2005-2021 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