Fiche d'espèce de Copépode
Calanoida ( Ordre )
    Ryocalanoidea ( Superfamille )
        Ryocalanidae ( Famille )
            Ryocalanus ( Genre )
Ryocalanus squamatus  Renz, Markhaseva & Laakmann, 2018   (F,M)
Ref.:
Renz & al., 2018 (p.6, Descr.F, M, figs.F, M, mol. biol., phylogeny)
Espèce Ryocalanus squamatus - Planche 1 de figures morphologiquesIssued from : J. Renz, E.L. Markhaseva & S. Laakmann in Zool. J. Linnean Soc., 2018, XX. [p.7, Fig.1]
Female (from 40.5808°N, 150.9833°): A-B, habitus (dorsal and lateral, respectively); C, rostrum (ventral); D, prosome posterior corners and urosome (lateral); E, urosome (ventral); F-H, paratype, prosome posterior corners and urosome (dorsal), ventral and lateral, tespectively); I, A1; J, segment XXVII-XXVIII of A1; K, scales on segment VIII-XI of A1.
Scale bars: A-I, K: 0.05 mm.
Nota:
- Prosome 4.8 times as long as urosome.
- Rostrum stout and strong, one-pointed.
- Cephalosome and pediger 1 partly fused, pedigers 4-5 separate.
- In lateral view, posterolateral corners of prosome extending posteriorly into points, reaching to middle of genital double-somite.
Pedigers 2-5 covered with fine spinules.
- Urosome 4-segmented. Genital double-somite and urosomites covered with rows of fine spinules.
- Genital double-somite slightly asymmetrical,, with lateral swelling on left side and ventomedial opening; in lateral view genital double-somite swollen ventroanteriorly. Seminal receptacles of oval shape.
- Caudal rami symmetrical with 2 lateral setae (II and III), 3 terminal setae (IV-VI) and 1 dorsal seta (VII).
- A1 24-segmented, extending to pediger 2, covered with scale-like structures.


Espèce Ryocalanus squamatus - Planche 2 de figures morphologiquesIssued from : J. Renz, E.L. Markhaseva & S. Laakmann in Zool. J. Linnean Soc., 2018, XX. [p.8, Fig.2]
Female: A, A2 (dotted seta added after paratype); B, Md palp; C, Md gnathobase; D, paratype, cutting edges of Md gnathobase; E, Mx1; F, paratype, Mx1 praecoxal arthrite seta in different positions; G, Mx2; H, paratype, Mx2 basal endite and endopod; I, Mxp.
Scale bars: A, H: 0.05 mm; B-D0, I: 0.1 mm.

Nota:
- Endopod 2-segmenyed; exopod incompletely 8-segmented (setal formula: 1, 3, 1, 1, 1, 1, 1, 3).
- Md: Gnathobase cutting edge with 7 unequal teeth plus ventral seta; exopodal segments with 6 setae; 1st endopodal segment with 2 setae, 2nd segment with 11 setae. Exopod to endopod ratio 0.82.
- Mx1: praecoxal arthrite with 9 terminal spines, 4 posterior and 2 anterior setae; coxal endite with 6 setae, coxal epipodite wiyj 9 setae; proximal basal endite with 4 setae, distal basal endite with 5 setae; endopod with 15 setae; exopod with 11 setae.
- Mx2: proximal praecoxal endite bearing 4 setae plus attenuation in holotype, 5 setae plus attenuation in paratype, distal praecoxal endite with 3 setae; coxa without outer seta, coxal endites with 3 setae each; proximal basal endite with 4 setae; endites 2-5 with surface spinules, remaining endopod with 8 setae.
- Mxp: syncoxa with 1 seta on praecoxal endite, 2 setae on proximal coxal endite, 3 setae on middle coxal endite, and 3 setae on distal coxal endite; syncoxa with fine rows of spinules; basis with 3 distal setae; endopod 6-segmented (setal formula: 2, 4, 4, 3, 3, 4 setae).

Rem. : In both sexes, the distal spine on the praecoxal arthrite of Mx1 shows a cavity at its tip, presumably a specific adaptation connected with feeding. This structure is observed in R. bowmani (see figure in this species. A morphologically similar structure can be found in the Md of Heterorhabdidae (see Ohtsuka & al., 1997). Some variability was observed in the armature of the proximal praecoxal endite of Mx2 between right and left limb of individuals in both female and male specimens (i.e. presence of 4 or 5 setae). Furthermore, this endite was always equipped with a short attenuation in females (a feature not reported before in other ryocalanid species).


Espèce Ryocalanus squamatus - Planche 3 de figures morphologiquesIssued from : J. Renz, E.L. Markhaseva & S. Laakmann in Zool. J. Linnean Soc., 2018, XX. [p.9, Fig.3]
Female: A, P1 (with endopod figured separately); B, P2; C, P3; D, rioght P4; E, left P4.
Scale bars: A-E: 0.1 mm.


Espèce Ryocalanus squamatus - Planche 4 de figures morphologiquesIssued from : J. Renz, E.L. Markhaseva & S. Laakmann in Zool. J. Linnean Soc., 2018, XX. [p.12, Table 3]
Female & Male: Seta and spine formula from Kurile-Kamchatka Trench.

Nota: Abnormalities were observed in the formation of a swimming leg, as in one female and one male specimen, exopods of P4 and P2, respectively, lacked lateral spines, and exopodal segment 3 lacked the terminal spine and deviated in the setation typical for this taxon.


Espèce Ryocalanus squamatus - Planche 5 de figures morphologiquesIssued from : J. Renz, E.L. Markhaseva & S. Laakmann in Zool. J. Linnean Soc., 2018, XX. [p.710, Fig.4]
Male (from 41.2000°N, 150.0833°E): A, habitus (lateral); B, habitus (dorsal), specimen damaged; C, rostrum (ventral view); D-E, posterior prosome and urosome (lateral and dorsal, respectively); F, left A1.
Scale bars: A-B, 0.5 mm; C-D: 0.1 mm.

Nota:
- Prosome 4.6 times as long as urosome.
- Rostrum stout, strong, one-pointed.
- Cephalosome andpediger 1 separate, pedigers 4 and 5 separte.- Pedigers 2-5 covered with fine spinules.
Caudal rami slightly asymmetrical, with 1 lateral seta (III), 3 terminal setae (IV-VI) plus 1 dorsal seta (VII).
- Left A1 unmodified, 24-segmented, extending to pediger 2, covered with scale-like structures.
- A2, Md, Mx1, Mxp similar to those of female.
- Mx2 as in female, with proximal praecoxal endite bearing 4 or 5 setae, but without attenuation.


Espèce Ryocalanus squamatus - Planche 6 de figures morphologiquesIssued from : J. Renz, E.L. Markhaseva & S. Laakmann in Zool. J. Linnean Soc., 2018, XX. [p.11, Fig.5]
Male: A, right A1; B, right A1 (segments XIX-XXVIII); C, right A1 (segments XXVI-XXVIII); D, right A1 (segments XVII-XIX, different position );E, P4 (coxa and basis); F, P5.
Scale bars: A-B, D-F: 0.1 mm; C: 0.05 mm.

Nota:
- Right A1 strongly modified for grasping, 23-segmented; segments XX to XXVI wider than on the left, segments XX to XXII-XXIII with surface spinules, segments XX and XXI with 1 proximal spine each; segments XXV and XXVI with strong lateral attenuations proximally, wegment XXII-XXIII fused;, hingesd occirring between segments XIX and XX, XX and XXI, and XXIII-XXIII and XXIV.
- P5 uniramous on both sides, covered with rows of spinules on posterior surface. Right leg with exopod 1-segmented, shorter than left leg, with terminal spine/ Left leg with exopod 3-segmented, terminal segment with 2 spines.

NZ: 1

Carte de distribution de Ryocalanus squamatus par zones géographiques
Loc:
NW Pacif. (Kurile-Kamchatka Trench)

Type locality: 40.5808° N, 150.9833° E.
N: 1
Lg.:
(1223) F: 2,05-2,17; M: 1,83; {F: 2,05-2,17; M: 1,83}
Rem.: Hyperbenthique (5400 m)
Voir aussi les remarques en anglais
Dernière mise à jour : 30/03/2019

 Toute utilisation de ce site pour une publication sera mentionnée avec la référence suivante :

Razouls C., Desreumaux N., Kouwenberg J. et de Bovée F., 2005-2021. - Biodiversité des Copépodes planctoniques marins (morphologie, répartition géographique et données biologiques). Sorbonne Université, CNRS. Disponible sur http://copepodes.obs-banyuls.fr [Accédé le 04 décembre 2021]

© copyright 2005-2021 Sorbonne Université, CNRS

Webmaster
Mentions légales et informations nominatives
CNRS   Observatoire Océanologique de Banyuls sur Mer - Laboratoire Arago
Sorbonne Université

 

Version française
English version

 

Rechercher

Sur le WEB du CNRS

 


Copépodes planctoniques marins

Copépodes planctoniques marins

 

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