Zygopa michaelis Holthuis, 1961

Zygopa michaelis Holthuis, 1961 View in CoL

( Figs. 1 View Figure 1 , 2 View Figure 2 )

Zygopa michaelis Holthuis, 1961: 22–26 View in CoL , figs. 1, 2. — Boyko, 2002: 204–210, figs. 66, 67 (and references therein).

Zygopa cf. michaelis Ortiz et al., 2013: 33 View in CoL , figs. 1e, 1l, 5a, 5b. — Lalana et al., 2014: 127.

Zygopa lalanai Ortiz, 2015: 84-91 View in CoL , figs. 1b, 2–7 (new synonym). — Diez and Espinosa, 2018: 140.

Remarks. Zygopa lalanai was purportedly distinguished from Z. michaelis by the shape of the ocular peduncles (tapered vs. rounded distally; Fig. 1B View Figure 1 vs. 1D), but this is the only character that appears to differ between the holotype (and only specimen) of Z. lalanai and the numerous known specimens of Z. michaelis (see Boyko, 2002). The carapace groove (CG) pattern is the same in both species, as evidenced by a comparison of the photographic fig. 7a in Ortiz (2015; Fig. 1A View Figure 1 ) and fig. 66a in Boyko (2002; Fig.1C View Figure 1 herein);note that the CGs are depicted inaccurately in the line drawing of Ortiz(2015:fig.2a) when compared to the photograph (Ortiz, 2015: fig. 7a; Fig. 1A View Figure 1 ). The dactyli of pereopods II and IV are identical in the two species (compare Ortiz, 2015: fig. 4b, d with Boyko, 2002: fig. 67b, d; Fig. 2A, C View Figure 2 vs. 2E, G) as is the dactylus of pereopod III (see Boyko, 2002: fig. 67c; Fig. 2F View Figure 2 herein), although in that case the photograph of the ventral view of the holotype of Z. lalanai (see Ortiz, 2015: fig. 7b) has to be used because the line drawing (fig. 4c; Fig. 2B View Figure 2 ) is not accurate. The shape of the telson is also the same in the two species (compare Ortiz, 2015: fig.5d and Boyko, 2002: fig. 67f; Fig. 2D View Figure 2 vs. 2H). The line drawings of the dactyli of pereopods II-IV as given fig. 6 of Ortiz (2015) are not useful and appear to have been drawn freehand; they are highly inaccurate as evidenced by comparison with the other figures and photographs.

Zygopa michaelis is known from both coasts of Florida, USA, to Brazil, in 4.0–73.2 m depth; the holotype of Z. lalanai was collected off Cuba in 6–8 m depth, a locality well within the known range of Z. michaelis .

As the only apparent difference between Z. lalanai and Z. michaelis is in the degree of the tapering of the ocular peduncles, this must be considered intraspecific variation, possibly age, size, or even preservation related, and the two species are synonymous. Zygopa at present contains only two valid species: Z. michaelis and Zygopa nortoni Serène and Umali, 1965 (known from the Philippines and New Caledonia, ranging to 60 m depth) ( Boyko, 2002).