Microcyclops minor Dussart, 1984

Gutierrez-Aguirre, Martha Angelica & Cervantes-Martinez, Adrian, 2023, Redescription of two species of Microcyclops (Copepoda, Cyclopoida) and use of ordination models to classify American species, ZooKeys 1173, pp. 111-130 : 111

Microcyclops minor Dussart, 1984

Fig. 3

Microcyclops anceps var. minor Dussart, 1984: 57, fig. 17.

Material examined.

Holotype. Dissected , adult female on slide labelled as: Microcyclops anceps var. minor [nov. var.]. Charca I, near Unaré river at Clarines ( Venezuela), 13.4.1981, Collector Bernard Dussart, and det. B. Dussart (MNHN Cp-673).

Redescription based on the holotype.

Dorsal margin of prosomal somites smooth (unfigured). Because of the position of the specimen, it was not possible to observe the buccal appendages.

As per the illustration by Dussart (1984), basipodites of P1 with short hair-like setules but without spine on medial margins; coxa with one row of short setules along lateral margins. Basipodite of P4 with short hair-like setules on medial margin (Fig. 3A ); P4 intercoxal sclerite rectangular with long setules along distal margin. As illustrated by Dussart (1984) Enp2P4 is 2.46 × as long as wide; medial spine 1.95 × as long as lateral spine and 0.73 × as long as the segment.

Fifth pediger bare, with dorsal hyaline membrane smooth posteriorly; P5 is a cylindrical free segment that bears one apical seta and one projected medial spinule (Fig. 3B ). Free segment of P5, 2.0 × as long as wide and 0.34 × as long as apical seta. Length to width ratio of caudal ramus is 3.15, medial margin naked; no spinules at base of lateral caudal setae, but spinules present at base of outermost terminal caudal setae (Fig. 3B ). Short spinules along all the posterior margin of anal somite; lateral caudal seta inserted at 78% of caudal ramus.

Relative lengths of terminal caudal setae from outermost to innermost caudal seta are 1: 6.2: 8.1: 2.33 (Fig. 3C ). Due to the differential morphological characteristics previously described, we propose to elevate the status of M. minor to the species level.

Figures

Figure 3. Microcyclops minor. Adult female (MNHN-Cp 673) A fourth leg, medial area: intercoxal sclerite, Bsp, and Enp 1 B urosome, dorsal C terminal caudal setae. Scale bars 50 µm.