Prendalona julietae Sousa, Elmoor-Loureiro & Santos, 2023

Sinev, Artem Y., Sousa, Francisco Diogo Rocha & Elmoor-Loureiro, Lourdes M. A., 2023, Revision of the guttata-group of Alona s. lato leads to its translocation to Prendalona Sousa, Elmoor-Loureiro & Santos, 2018 (Cladocera: Anomopoda: Chydoridae), Zootaxa 5293 (1), pp. 95-121 : 112-114

Prendalona julietae Sousa, Elmoor-Loureiro & Santos sp. nov.

Fig. 11–12 .

Sousa et al. (2016 a): 4–13, fig. 1–3, 11A–C ( Alona cf. guttata ).

Etymology. This new species is named in honor of Julieta Abdu El-moor, mother of Lourdes M. A. Elmoor-Loureiro.

Type locality: Artificial pond at Fontes do Ipiranga State Park (23°38ʹ19.7ʺS, 46°37ʹ16.5ʺW), São Paulo, Brazil .

Type matetrial. Holotype. Parthenogenetic female deposited at the Museum of Zoology of the S„o Paulo University, accession number MZUSP41593 .

Allotype. A male deposited at the Museum of Zoology of the S„o Paulo University, accession number MZUSP41594 .

Paratypes. A parthenogenetic female deposited at the Museum of Zoology of the S„o Paulo University, accession number MZUSP41595 .

Material studied earlier: see Sousa et al. (2016 a).

Description. Parthenogenetic female. General Body ( Fig. 11A ), oval in lateral view, of a moderate height; maximum height at middle of the body, in adults height/length ratio about 0.67. Dorsal margin uniformly curved; posterodorsal and posteroventral angles broadly rounded; posterior margin uniformly curved; ventral margin almost straight; anteroventral angle rounded.

Valves oblique. Ventral margin of valves with 32–35 setae, anterior setae very short ( Fig. 11B ). Posterodorsal angle with about 30 setulae ( Fig. 11C ).

Head. Compound eye larger than ocellus. Head shield without any sculpture, with a broadly rounded posterior portion. Three main pores, posterior and anterior pores larger than median pore; PP about 0.3–0.5 IP; lateral head pores located at level between median and anterior pores, distance from midline slightly shorter than IP.

Labrum. Labral keel without a prominence at anterior margin, posterior margin of keel with two clusters of setulae. Posterior part of labrum ( Fig. 12A–C ) in most specimens covered with epibiont bacteria.

Postabdomen ( Fig. 11D ) short, about 2.4 times as long as wide; preanal angle evident, preanal margin longer than anal and postanal margin. Anal margin slightly concave, with 3–4 groups of denticles. Postanal margin with distal portion acute, truncated, 6–7 well-developed marginal denticles, each with several spinulae on the anterior margin. Postabdominal claw similar in length to the anal margin, with one group of short spinulae on the base; pecten armed with one row of inner and outer spinulae; outer row with spinulae of similar length; distal spinulae on inner row longer than others.

Morphology of antennule and antenna typical for the genus. Morphology of thoracic limbs typical for the genus. Thoracic limb I without seta i on endite 1. Thoracic limb III with seta 4 longer than seta 5.

Ephippial female unknown.

Male. General. Body low oval ( Fig. 11E ), with maximum height at the middle, body height/length ratio about 0.62. Compound eye larger than ocellus.

Postabdomen ( Fig. 11F ) short, moderately wide, evenly narrowing distally. Postanal margin of postabdomen evenly comes to the base of claws, no distinct distal margin and dorsodistal angle. Length about 2.5 height. Ventral margin straight or weakly convex. Sperm duct opens at the end of postabdomen, forming minute protrusion above the base of claws. Dorsal margin almost straight in postanal portion. Preanal and postanal angles not defined. Preanal margin weakly convex to straight. Distal portion of postabdomen 2.5 times longer than preanal one; anal and postanal portions of similar length. Postanal margin with clusters of setulae of even thickness. Lateral groups of setulae as in female. Postabdominal claw ( Fig. 11G ) weakly curved, shorter than in female, much shorter than preanal margin of postabdomen, with acute tip without cluster of setulae. Basal spine very short, with a long spinule, longer than basal spine, near it. Antennule ( Fig.11H ) with male seta located at 2/3 distance from the base, its length about 0.4 length of antennule.

Thoracic limb I ( Fig. 11I ) of typical for the genus morphology, endite 1 without seta i.

Size. Length of parthenogenetic females 0.23–0.35 mm; of males 0.25–0.26 mm.

For full description see Sousa et al. (2016 a).

Differential diagnosis: P. julietae sp. nov. differs from P. arvensis in three main head pores and in labral keel without a prominence on anterior margin, and from P. werestschagini in (1) a smaller size, (2) smaller IP/PP ratio, and (3) a shape of both male and female postabdomen. P. julietae sp. nov. differs from P. barbulata in (1) head shield with broadly rounded posterior portion, (2) female postabdomen with acute prominent distal angle and strongly prominent preanal angle, (3) absence of seta i on endite 1 of thoracic limb I, and (4) evenly narrowing distally male postabdomen. Parthenogenetic females of P. julietae sp. nov. have similar morphology with those of P. guttata . Male of P. julietae sp. nov. differs from that of P. guttata in presence of a very long setule near basal spine of the postabdominal claw (this setule is longer than basal spine).

Distribution and ecology: P. juliate sp. nov. has a wide distribution in Brazil with occurrence in different types of aquatic ecosystems ( Sousa et al. 2016 a). It might be considered one of the most common alonine species in Brazil.

Figures

FIGURE 11. Prendalona julietae sp. nov. Parthenogenetic female. A, lateral view. B, anteroventral angle of valves. C, posteroventral angle of valves. D, postabdomen. Adult male. E, lateral view. F, postabdomen. G, postabdominal claw. H, antennule (after Sousa et al., 2016a)

FIGURE 12. Prendalona julietae sp. nov. Parthenogenetic female. A–C – labrum (note posterior part overgrown by epibiont bacteria).