Microcyclops echinatus Fiers, Ghenne & Suarez-Morales , 2000

Gutierrez-Aguirre, Martha Angelica & Cervantes-Martinez, Adrian, 2016, Taxonomic evaluation of eleven species of Microcyclops Claus, 1893 (Copepoda, Cyclopoida) and description of Microcyclopsinarmatus sp. n. from America, ZooKeys 603, pp. 33-69 : 41-42

Taxon classification Animalia Cyclopoida Cyclopidae

Microcyclops echinatus Fiers, Ghenne & Suarez-Morales, 2000 Figures 12, 13

Description of female.

This description is a complement to the original description of Fiers et al. (2000). Frontal surface of antennal basis with one basal, inner row of spinules arranged in an arc, and one longitudinal row of spinules near lateral margin (Fig. 12A). Antenna with three-segmented endopod bearing 1, 9, and 7 setae, respectively (Fig. 12B). Caudal surface of antennal basis with two rows of long spinules next to exopodal seta, one group of long spinules at basal position, one basal row on inner margin and another basal row on outer margin (Fig. 12B). Nine teeth on the distal margin of the labrum (Fig. 12C). Eight teeth present on gnathobase of mandible (Fig. 12D). Maxillular palp with three apical setae (one of these setae armed with long setules); lateral lobe with three setae, the longer seta armed; proximal seta nude (Fig. 12E). Maxillar basipodite with one claw-like projection bearing thin spines on concave margin and one long seta with one (Fig. 12F) or four tiny spinules ( Fiers et al. 2000); maxilla with two-segmented Enp bearing 2 and 3 setae on first and second endopodal segments, respectively (Fig. 12F). Maxilliped with syncoxa (3 setae), basis (2 setae), and two-segmented Enp bearing 1 and 3 setae. Syncoxa and basis of maxilliped with rows of spinules on caudal surface (Fig. 12G).

Two pores on lateral margin of second endopodal segment of P1, very long spinules present at insertion of apical spine of Enp2P1. Long medial spine of P1 basis with heteronomous setulation (Fig. 13A). Inner margin of P1−P3 basis with long hair-like setae (Fig. 13A, B), inner margin of P4 basis with one row of tiny spinules and one row of long setules (Fig. 13C). Intercoxal sclerites of all swimming legs ornamented on caudal surface: P1 with one row of spinules and P2 to P4 with two rows of spinules (Fig. 13 A–C). Enp2P4 2.5 ± 0.1 times as long as wide; medial spine is 2.0 ± 0.1 times as long as lateral spine, and 0.8 ± 0.1 times as long as the segment.

Fifth pediger with rows of spinules on ventro-lateral surfaces. Fifth leg with tiny spinule on inner margin (Fig. 13D); cylindrical free segment 3.7 ± 0.1 times longer than wide and 0.45 ± 0.01 times as long as distal seta of P5. Caudal ramus 5.9 ± 0.4 times longer than wide. Seta VII 0.5 ± 0.1 times as long as caudal ramus, seta VI 0.5 ± 0.05 times as long as caudal ramus. Relative lengths of terminal caudal seta from outermost to innermost caudal seta, 1.0: 6.5: 10.4: 2.0. Seta IV and seta V with homonomous setulation, bearing long and fine setules (Fig. 13E).