Notodiaptomus anisitsi (Daday, 1905)

Perbiche-Neves, Gilmar, Boxshall, Geoffrey Allan, Previattelli, Daniel, Nogueira, Marcos Gomes & da Rocha, Carlos Eduardo Falavigna, 2015, Identification guide to some Diaptomid species (Crustacea, Copepoda, Calanoida, Diaptomidae) of " de la Plata " River Basin (South America), ZooKeys 497, pp. 1-111 : 23-24

Taxon classification Animalia Calanoida Diaptomidae

Notodiaptomus anisitsi (Daday, 1905) Figs 25, 26, 27, 28

Diaptomus anisitsi Daday, 1905

Diaptomus inflexus Brian, 1925

Diagnosis.

Adult male, body length 1144 µm. Row of spinules present along posterior margins of Ped3 and Ped4 (Fig. 26A, B), Ped4 and Ped5 completely fused; A1R with well-developed spinous process on segments 15 and 16 (Figs 25A, 26C, E, F); segment 20 often with short curved distal process (Fig. 26C). Right Exp2P5 with two small nodules on surface (Fig. 25B); and bearing curved lateral spine inserted in middle of segment margin (Fig. 26G, H), and nearly half as long as terminal claw.

Adult female, body length 1309 µm. Single row of spinules present along posterior margin of Ped3; irregular rows of spinules present, marking plane of posterior margin of Ped4; discrete transverse row of minute spinules present across middle of Ped5 (Fig. 27A). Lateral wings asymmetrical, similar in size but left wing located more anteriorly and right wing positioned and directed more posteriorly; both lateral wings with single sensilla at apex (Fig. 27A). GS nearly symmetrical, no more than 20% longer than wide; dilated anteriorly with left and right swellings of similar size, left sensilla on apex of swelling and aligned perpendicular to longitudinal axis of body; right sensilla directed postero-laterally. P5 symmetrical (Fig. 27B) with conical process at outer distal corner of CxP5 bearing strong triangular sensilla at apex. BspP5 with long outer seta, extending beyond middle of outer margin of Exp1P5. EnpP5 2-segmented, not reaching middle of inner margin of Exp1P5. ExpP5 3-segmented; lateral spine of Exp2P5 about as long as outer margin of Exp3P5; external seta of Exp3P5 less than 1/4 (25%) length of internal seta; internal seta almost reaching tip of terminal claw.

Remarks.

The specimens illustrated were collected from the lower Paraná River (RPAR-L2). This species appears to be widely distributed in the south of the basin, from the Iguaçu River into more temperate conditions (Fig. 28).

Paggi (2001) provided good illustrations of this species and, in the same work, described a new species, Notodiaptomus dentatus Paggi, 2001, resembling and potentially confused with Notodiaptomus anisitsi . These two species deserve further investigation, as they may be part of a larger complex of species with very similar morphology.