Calanoida ( Order )
    Diaptomoidea ( Superfamily )
Sulcanidae Nicholls, 1945 ( Diaptomoidea )
Ref.: Nicholls, 1945 c (p.513); Andronov, 1974 a (p.1005); Bowman & Abele, 1982 (p.9); Razouls, 1982 (p.627); Dussart & Defaye, 1983 (p.45); Huys & Boxshall, 1991 (p.406, 419); Barthélémy, 1999 a (p.28); Bradford-Grieve, 1999 b (p.211, Def.); Ohtsuka & Huys, 2001 (p.461); Boxshall & Halsey, 2004 (p.12; 49; 202: Def.); Blanco-Bercial & al., 2011 (p.103, Table 1, Fig.2, 3, 4, molecular biology, phylogeny); Laakmann & al., 2019 (p.330, fig. 2, 3, phylogenetic relationships)
Bradford-Grieve J.M., (2002 onwards). Key to calanoid copepod families. Version 1 : 2 oct 2002. http://www.crustacea.net/crustace/calanoida/index.htm
Rem.: Brodsky, 1980 (pers. comm.) places this family after that of the Tortanidae.
1 G.: Sulcanus Nicholls, 1945 (mainly in estuarine waters).

Definition after Boxshall & Halsey (2004, p/202) :
- Prosome 5-segmented, cephalothorax incorporating 1st pedigerous somite, pedigerous somites 4 and 5 separate.
- Posterolateral angles of last pediger, slightly asymmetrical, producede into spinous processes ;
- Urosome 4-segmented in female ; with 3 free abdominal somites.
- Genital apparatus female comprising genital aperture located medially on ventral surface of genital double-somite ; copulatory pore contained within median genital aperture.
- Urosome 5-segmented in male (genital somite and 4 free abdominal somites) ; single genital aperture located ventrolaterally at posterior rim of genital somite on left side.
- Caudal rami with up to 6 setae.
- Rostrum weakly developed, may be represented by pair of minute rostral filaments.
- Nauplius eye large, all 3 ocelli developed.
- A1 indistinctly 16-segmented in female, with considerable fusion proximally ; segmental homologies (based on Sulcanus conflictus) : segment 1 (I) free, segment 2 (compound II-X), segment 3 double (XI-XII), segment 4 double (XIII-XIV), segments 5 (XV) to 15 (XXV) separate, apical (13yj) segment triple (XXVI-XXVIII).
- A1 18-segmented and geniculate on right side in male between 16 and 17 ; proximal segments better defined than in female ; segmental fusions associated with geniculation XXI-XXIII and XXIV- XXVIII.
- A2 uniramous ; no trace of exopod ; 3-segmented, proximal segment (coxa) very short, unarmed ; middle segment (allobasis) extremely elongated a,d armed with single seta (basl in origin) near midlength, distal segment (fused 2 nd and 3rd endopodal segments) slender, not bilobed, with 6 long setae apically.
- Labrum with paired lateral lobes either side of medial lobe.
- Md biramous ; coxa with well developed gnathobase ; palp with unarmed basis, 2-segmented endopod, indistinctly 4-segmented exopod ; endopodal segment 1 unarmed, segment 2 with 4 setae ; exopodal setation 1, 1, 1, 2.
- Mx1 reduced, 2-segmented ; segment 1 with 11 elements along inner margin (possibly representing praecoxal arthrite) ; segment 2 small, bearing 3 elements distally.
- Mx2 with praecoxa and coxa fused, setation formula of endites 0, 1, 2, 2 ; basis with 1 long spinulate seta ; endopod indistinctly segmented, with 5 long spinulate setae.
- Mxp 3-segmented ; syncoxa well developed with 2 short setae and 3 long spinulate setae reaching anteriorly ; distal part of Mxp reduced to 2-segmented vestige, segment 1 unarmed, segment 2 with 3 small elements.
- Swimming legs P1 to P4 biramous, 3-segmented exopods ; endopods 2-segmented (fusion of 1st and 2 nd endopodal segments).
- Inner seta on basis of P1 absent, tiny outer seta on basis.For Bradford-Grieve (1999 b, p.211) this family has affinities with the Parapontellidae and Tortanidae. Is most outstanding features are a uniramous A2, with greatly elongated segments; the long setae, particularly on Mx2 and Mxp; and the peculiar structure of the anal region. The absence of fully articulated outer edge spines on the exopods of P2-P4, is reminiscent of the Acartiidae.
Family Sulcanidae - Plate 1Issued from : G.A. Boxshall & S.H. Halsey in An Introduction to Copepod Diversity. The Ray Society, 2004, No 166, Part. I. [p.203, Fig. 51].
Sulcanus conflictus: A, habitus female; B, A1 male; C, A2 female; D, Mx1 female; E, Mxp male; F, P5 female. [After Nicholls, 1945 d]

Family Sulcanidae - Plate 2Issued from : G.A. Boxshall & S.H. Halsey in An Introduction to Copepod Diversity. The Ray Society, 2004, No 166, Part. I. [p.202].
Armature formula of swimming legs P1 to P4. Outer spines on all exopodal segments of legs 2 to 4 fused to segment; outer spines on 3rd exopodal segment of leg 1 distinct at base.

Nota : P5 female comprising broad transverse plate formed by fusion of coxae and intercoxal sclerite. Each leg 3-segmented and uniramous ; comprising unarmed basis and 2-segmented exopod. 1st exopodal segment unarmed, 2nd tapering distally, slightly curved and claw-like ; outer margin strongly serrated on right side only.
- Male P5 asymmetrical ; intercoxal sclerite and protopodal segments fused to form robust trnsverse plate ; right leg with muscular basal pedestal carrying curved, claw-like unsegmented exopod distally and 3 processes on inner margin, one of which probably representing endopod. Left leg uniramous, lobate, indistinctly subdivided into robust, muscular proximal part and rounded distal part armed with 1 to 3 setae.
- Eggs released into water.

Remark: Apparently there is a mistake in the formula on P1: the seta is on inner of coxa and not on inner of basis.

Family Sulcanidae - Plate 3Issued from : J.M. Bradford-Grieve in NIWA Biodiversity Memoir, 111, 1999. [p.211].
Setal formula of swimming legs P1 to P4.
- P5 uniramous, 3-segmented, and slightly asymmetrical in female.
- Left P5 male uniramous and right leg biramous, with both strongly modified.

Note on the distal inner part of basipod 1 (= coxa) the presence of one seta.
(1) Sulcanus Nicholls, 1945
Ref.: Nicholls, 1945 c (p.511); Razouls, 1982 (p.627); 1993 (p.507); Mauchline, 1998 (p.66); Bradford-Grieve, 1999 b (p.211, Def., Rem.)
Rem.: type: Sulcanus conflictus Nicholls, 1945. Total: 1 sp.
For Bradford-Grieve (1999 b, p.211) the single species of this genus has affinities with the Parapontellidae and Tortanidae. Euryhaline genus and the type species described from the mouth of the Georges River (salinity about 1/4 that of the open sea)

Diagnosis after Bradford-Grieve (1999 b, p.211) :
- Head without lateral hooks.
- Eye prominent, without cuticular lenses.
- Rostrum absent.
- Labrum prominent and with accessory lobes.
- Head and pedigerous segment 1 fused, pedigerous segments 4 and 5 separate.
- Posterior metasome rounded, with posterior spines and almost symmetrical in both sexes.
Female urosome 4-segmented.
- Female genital segment without genital operculum or seminal receptacles.
- Male urosome 5-segmented.
- Anal segment cleft almost to its base, dorsally excavaded, and overhung by a large anal operculum.
Caudal rami eymmetrical in female; slightly asymmetrical in male, right ramus being longer and wider than left ramus.
Female A1 16-segmented with segments more or less fused and with tubercles at bases of large setae.
- Male right A1 geniculate and with 18 distinct segments.
-A2 uniramous, 3 segmented, 2 terminal segments elongate, with a terminal bunch of long setae; exopod lacking.
- Md palp biramous; exopod subterminal, unsegmented; endopod terminal, 2-segmented.
- Maxillae 1 and 2 with reduced segmentation but strongly armed with long curved denticulate spines.
- Mxp with basal portion enlarged and extending beyond the point of insertion of the distal portion, and bearing long, strong, curved, denticulate spines; terminal portion reduced, 2-segmented.
- Basipods of swimming legs increase in length from P1 to P3. Endopods 2-segmented on P1 and P2, 3-segmented on P3 and P4. Distolateral borders of exopod segments of P2-P4 (except exopodal segment 2 of P2) expanded into a conspicuous tooth; these spines do not seem to be com^metely articulated. Terminal exopod spine of P1 -P4 with outer edge teeth.
- P5 uniramous , 3-segmented, and slightly asymmetrical in female; in male the left leg is uniramous and right leg is biramous, with both strongly modified.
Remarks on dimensions and sex ratio:
The mean female size is 1.5 mm (1.6-1.4 mm), and the mean male size is 1.55 mm (1.5-1.6 mm)

 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., 2005-2022. - Biodiversity of Marine Planktonic Copepods (morphology, geographical distribution and biological data). Sorbonne University, CNRS. Available at http://copepodes.obs-banyuls.fr/en [Accessed January 23, 2022]

© copyright 2005-2022 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