Mesocletodes angolaensis 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 angolaensis

description: Mesocletodes angolaensis sp. nov.   
(Figs 2–6)  
 Etymology. The species name refers to the sampling location, the Angola Basin.   
 Locus typicus: Angola Basin (off Angola), RV „Meteor“, Cruise M-48/1, 27.07.2000.   
 Holotype: 1 male, dissected, mounted on 9 slides, coll. no. SMF 31430/1–9 at station 346/1 (16°17’S, 05°27’E, 5389m).   
 Description of male. Habitus (Figs 2 A, C, D) of cylindrical shape. Body length 642µm. No clear distinction between prosome and urosome. Distal margins of cphth and free thoracic somites with denticulated, textured hyaline frill (Fig. 2B) and, except the penultimate somite, with fine, long sensilla. Urosomites with long spinules inserting just anteriorly of the hyaline frill. Rostrum not protruding, with 2 sensilla. Cphth without cuticular process, dorsally and laterally with slight depressions, cuticula with nearly symmetric pattern and symmetrically arranged sensilla. Ventral margin of cphth with small spinules and few sensilla. Telson nearly square from dorsal view, slightly tapering posteriorly, ventrally with spinules, dorsally with strong, cuticular process (Fig. 6A). Cuticular process on telson with basal swelling, distally peaked, long and narrow. Laterally with 1 sensillum on each side. Lateral edges of pleurotergites of P2–P4 bearing prosomites with thickened cuticula and several spinules. P3–P4 bearing somites with 2 dorsal hyaline protrusions each bearing a long sensillum and, laterally of these, a row of spinules. P5 bearing somite laterally with 2 rows of small spinules and few strong spinules close to the hyaline frill.   
A1 (Fig. 3A) 7-segmented, haplocer, acrothek on segments IV and VII. First segment without seta, ornamented with strong spinules proximally and subdistally, with small spinules subdistally on anterior face. Second segment with a strong protrusion bearing a strong, bipinnate seta. Segment III very short. Aes of segment IV extremely elongate and large. Segments IV and V with 2 and 1 tripinnate seta(e) respectively. Segments IV–VII arranged in a loop. Spines of A1 with 1 STE each.  
Setal Formula: I:0, II:7, III:3, IV:5+Aes, V:2, VI:2, VII:7+Aes.  
A2 (Fig. 3B) with basis, seemingly without exp. Enp1 with 6 long spinules. Enp2 with 3 long and several small spinules, 2 medial spines with 1 STE each, terminally with 4 bipinnate setae, 2 of which geniculated.  
Mouthparts atrophied, could not be traced due to their strong reduction.  
P1 (Fig. 4A) coxa with several rows of spinules, with fine spinules close to inner and with coarser spinules close to outer margin. Basis at inner margin with setular tuft, with 1 inner and 1 outer spine. Exp 3- segmented. Exp1 and Exp2 without inner armature. Exp3 with 1 outer bipinnate spine with STE, 2 terminal and 1 inner, bipinnate seta. Enp 2-segmented. Enp1 without inner seta, Enp2 with 1 inner, 1 terminal and 1 outer, bipinnate seta. Outer seta short and with STE. All segments with inner setules and outer spinules. Spinules near insertion of spines. Intercoxal sclerites are U-shaped and bare. Setal formula as in Table 1.  
P 2–P 4 (Figs 4B; 5A, B, C) coxa with spinules as shown for P3. Basis with inner setular tufts and outer seta (as illustrated for P4). Exp 3-segmented. Exp1 with fine spinules at inner margin. Exp2 with inner, bipinnate seta. Exp3 with 2 outer, bipinnate spines, 1 terminal, unequally bipinnate spine and 1 bipinnate seta, with 2 (P2 and P3) or 1 (P4) inner, bipinnate seta(e). Enp biarticulate. Enp1 with inner, bipinnate seta and fine, outer spinules. Enp2 of P2 and P3 with 4 bipinnate setae, Enp2 of P4 lost during dissection. Spinules near insertion of spines. Intercoxal sclerite as in P1. Setal formula as in Table 1.  
P 5 (Fig. 6B) outer part of basenp with setophore, 3 spinules and long bipinnate seta. Inner part of basenp barely protruding, with 1 long, strong, inner seta and 1 short, bare, outer seta. Exp about 4 times longer than basal width, proximally with 2 long spinules, 2 outer, 1 terminal and 1 inner setae and 1 STE. Setal formula as in Table 1.  
P 6 reduced to 1 seta.  
Furcal rami (Fig. 6A) about 13 times longer than wide at their insertion. Entirely covered by spinules, insertion surrounded by coarse spinules of anal somite. Furcal ramus with 7 setae: I and II close together laterally in proximal third, seta III inserted subdistally dorsolaterally, IV, V and VI inserting terminally, VII dorsally in the middle. Setae I, II, III, IV and VI bare, Seta V broken, seta VII triarticulated and bare. Furcal ramus with tube pore terminolaterally (highlighted by arrow in Fig. 6A).  
Female 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 216-222, DOI: 10.11646/zootaxa.2096.1.14, http://zenodo.org/record/5320482