Mesocletodes dorsiprocessus Menzel & George, 2009, sp. nov.
Creators: name: Menzel, Lena
name: George, Kai Horst
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Hexanauplia
Harpacticoida
Argestidae
Mesocletodes
Mesocletodes dorsiprocessus

description: Mesocletodes dorsiprocessus sp. nov.   
(Figs 12–17)  
 Etymology. The name refers to the bifid cuticular processes in P2–P5-bearing somites and first urosomite.   
 Locus typicus: Angola Basin, (off Angola), RV „Meteor“, Cruise M-48/1, 27.07.2000.   
 Holotype: 1 female, dissected, mounted on 12 slides, coll. no. SMF 31428/1–12 at station 346/4 (16°16.9’S / 05°27.0’E, 5389m).   
 Paratype: 1 female mounted on 1 slide, coll. no. SMF 31429/1 at station EBS 340 (start: 18°18.3’S 004°41.3’E; end 18°19.4’S 004°41.9’E, 5395m).   
 Description of female. Habitus (Fig. 12A) of cylindrical shape, no clear distinction between prosome and urosome. Body length 1105µm. Rostrum small, not protruding, with 2 sensilla. Cphth dorsally with cuticular process, process triangular, curved posteriorly. Distal margins of cphth and body somites with denticulated hyaline frill. Long sensilla on distal margins of body somites, except the penultimate one. Body somites with rows of spinules, increasing in length and breadth posteriorly. P3–P5 bearing somites and second urosomite dorsally with bifid cuticular processes. Telson quadrate, with several strong spinules and bifid cuticular process dorsally, peaked upward, posterior tip longer than anterior. Laterally, 1 sensillum on each side. Genital doublesomite incompletely fused. P2–P4 bearing somites with thickened cuticula near insertion of the legs.   
A1 (Fig. 13A) 8-segmented, acrothek on segments 4 and 8 proximally with corona of spinules and several spinules scattered across the surface. Second segment with strong protrusion bearing a strong, bipinnate seta. Third segment elongated. Spines of A1 with 1 STE each. All segments covered by fine spinules.  
Setal formula: I:0, II:8, III:5, IV:2+Aes, V:1, VI:3, VII:6; VIII: 6+Aes.  
A2 (Fig. 15A) coxa short and unarmed. Basis with fine spinules. Exp 1-segmented, with 2 bipinnate setae. Enp1 and 2 with fine, inner spinules and 4 outer spinules each. Enp2 with 2 medial, bipinnate spines with 1 STE each and 6 terminal elements. 1 outer bipinnate spine, 2 geniculated, bare setae, 1 bipinnate spine, 1 bipinnate spine with STE, spine fused with 1 fine bare seta at the basis.  
Paragnaths (Fig. 13B) with few short, fine spinules medially and many very long spinules laterally, ventrally of these long spinules are broad spinules with distal brushes; ventral surface covered in small spinules.  
Md (Figs 14B, C) gnathobase with broad grinding face. Dorsally with transformed denticulated seta, beneath 2 spoonlike setae, followed by several strong toothlike elements. Palpus 1-segmented, with spinules and 1 basal seta, 1 exopodal and 1 endopodal seta.  
Mxl lost during preparation.  
Mx (Fig. 14A) syncoxa with 2 endites. Proximal endite with 1 seta, distal endite well developed with 3 terminal setae: 1 strongly bipinnate seta incompletely fused to the endite, 1 bipinnate and 1 bare seta. Basis with long spinules and 3 setae: 1 seta incompletely fused to basis, 1 strong seta and 1 bare seta subterminally. Enp 1-segmented, very small, with 2 setae.  
Mxp (Fig. 13C) syncoxa with 1 tripinnate seta, many very fine spinules and 3 rows of strong spinules. Basis with long inner spinules and many spinules dorsally. Enp 1-segmented, fused to strong claw (broken off).  
P1 (Fig. 16A) coxa with several spinules. Basis with 1inner and 1 outer spine. Exp 3-segmented. Exp1 and 2 inner margin without armature. Exp3 with 2 bipinnate spines with 1 STE each, 1 bipinnate seta terminally and 1 bare inner seta. Enp biarticulate. Enp1 with 1 bare inner seta. Enp2 with 1 bare inner seta and 1 bipinnate and 1 bare seta terminally. Strong spinules at insertions of spines, all segments with fine spinules. Setal formula as in Table 3.  
P 2–P 4 (Figs 16B; 17A, B) coxae with several spinules. Bases with outer seta only. Exp 3-segmented. Exp1 with hairy outer spinules, without inner seta. Exp2 with inner bipinnate seta and outer spine. Exp3 with 2 bipinnate outer spines, 2 bipinnate setae terminally and 2 (P2 and P3) or 1 (P4) inner bipinnate setae. The terminal outer spine of P4 Exp3 is probably broken off. Enp biarticulate. Enp1 with bare inner seta. Enp2 with 3 setae (P2) or with 2 setae (P3 and P4). All spines with spinules at their insertion points. Setal formula as in Table 3.  
P 5 (Fig. 15B) basenp with several spinules. Outer lobe of basenp with setophore bearing 3 spinules and 1 outer seta. Inner lobe not protruding, with 1 short outer and 1 long median bipinnate seta (lost during preparation, only insertion point remained). Net-like structure between inner and outer lobe of basenp. Exp approximately 9 times longer than broad, with 5 setae and 1 terminal tube pore. Exp covered with spinules. Setal formula as in Table 3.  
Furcal rami (Fig. 12B) approximately 13 times longer than broad (the widest part measured at its base), the insertion surrounded by spinules of anal somite. Furcal ramus completely covered by spinules, with strong terminal tube pore and 7 setae: I and II in the middle of caudal ramus, seta III subdistally, setae IV, V and VI distally, seta VII dorsally in distal half. Seta I, III, IV and V lost during preparation, seta I and VI bare, seta VII triarticulate and bare.  
Male unknown.
description: Published as part of Menzel, Lena & George, Kai Horst, 2009, Description of four new species of Mesocletodes Sars, 1909 (Copepoda, Harpacticoida, Argestidae) and redescription of Mesocletodes robustus Por, 1965 from the South Atlantic, including remarks on the Mesocletodes abyssicola- group *, pp. 214-256 in Zootaxa 2096 (1) on pages 228-232, DOI: 10.11646/zootaxa.2096.1.14, http://zenodo.org/record/5320482