Brasilocypria ricardopintoi, Almeida, Nadiny Martins De, Ferreira, Vitor Góis, Martens, Koen & Higuti, Janet, 2023

Almeida, Nadiny Martins De, Ferreira, Vitor Góis, Martens, Koen & Higuti, Janet, 2023, 5237, Zootaxa 5237, pp. 1-88 : 32-33

Brasilocypria ricardopintoi gen. et spec. nov.

( Figs 16–19 )

2007? Physocypria schubarti Higuti et al. : 1935, table 2.

2009 Physocypria schubarti Higuti et al. : 664, table 1.

2010 Physocypria schubarti Higuti et al. : 267, 269, tables 2, 4.

2015a? Physocypria schubarti Matsuda et al. : 326, table 1.

2015b? Physocypria schubarti Matsuda et al. : 118, table 1.

2017b? Physocypria schubarti Higuti et al. : 5, appendix 1.

2017? Physocypria schubarti Conceiç „o et al.: 5, table 2.

2020? Physocypria schubarti Conceiç „o et al.: 1670, 1677, fig. 4, table 2.

2020? Physocypria schubarti Higuti et al. : 2, table S1.

2020? Physocypria schubarti Rosa et al. : 29, table 1.

2021? Physocypria schubarti Campos et al. : 7, table 1.

2021? Physocypria schubarti Rosa et al. : 229, 230, 234, 235, figs. 2,6, tables 1,3.

Diagnosis. Cp with suboval shape, LV overlapping RV, except in the middle of dorsal margin, anterior overlap the largest. Posterior marginal tubercles more prominent than anterior ones. CpV and CpD narrow.A2 with natatory setae well-developed, accompanying seta absent; male A2 with four-segmented endopodite, setae t2 and t3 transformed into sexual bristles. Rpp and Lpp asymmetrical. Rpp with sharply pointed distal corner of first segment; second segment with strongly curved dorsal margin. Lpp shorter and narrower, distal segment sickle-shaped, smoothly curved. T1 with one long and hirsute seta next to the two a-setae. T2 without d1 and d2 setae. T3 without d2-seta. CR with a long proximal seta. Hp with ls and ms elongated and subequal in length.

Differential diagnosis. Brasilocypria ricardopintoi gen. et spec. nov. can be distinguished from other Physocypria s.l. species by the morphology of the prehensile palps and Hp. Thus far, no other species of Physocypria s.l. has been recorded with similar morphological characteristics of the male reproductive organs. However, regarding the shape of the carapace, especially by the presence of a large overlap of the LV over the RV, especially anteriorly, B. ricardopintoi gen. et spec. nov. is similar to Keysercypria affinis , Physocypria biwaensis Okubo, 1990 , P. bullata , K. deformis and Physocypria longiseta Klie, 1930 . However, the new species differs from all of these species in the shape of the dorsal margin of the LV, which is rounded and with the greatest height situated at the middle of the valve in K. affinis and P. longiseta , near to the anterior region in K. deformis and is also more straight in B. ricardopintoi gen. et spec. nov., with the greatest height situated closer to the posterior region. Physocypria biwaensis has an arched dorsal margin of the LV, while P. bullata has a very large dorsal expansion on the RV and both of these characters are absent in B. ricardopintoi gen. et spec. nov.

Brasilocypria ricardopintoi gen. et spec. nov. has a compressed shape in lateral view, which is also observed in B. lordi gen. et spec. nov., but the first species has a large overlap along the antero and posteroventral margins, while the second species has a smaller overlap there.

Material examined. Type locality: Alluvial valley of the upper Paraná River floodplain, Banhado Lake ( PAR 255 ), in floating macrophytes. Coordinates : 22°33′58.6′′ S, 53°23′10.4′′ W .

Type material: Holotype: A male, with soft parts dissected in glycerine in a sealed slide and with valves stored dry in a micropaleontological slide ( MZUSP 43111 ).

Allotype: A female, dissected and stored as the holotype ( MZUSP 43112 ).

Paratypes: Two males dissected and stored as the holotype ( MZUSP 43113 , MZUSP 43114 ) . Three male carapaces stored dry in micropaleontological slides ( MZUSP 43115 , MZUSP 43116 , MZUSP 43117 ) .

Two females dissected and stored as the holotype ( MZUSP 43118 , MZUSP 43119 ). Three female carapaces stored dry in micropaleontological slides ( MZUSP 43120 , MZUSP 43121 , MZUSP 43122 ) .

Etymology: The present species is named in honour of Prof. Ricardo Lourenço Pinto (Brasília, Brazil) in recognition of his important contribution to the knowledge of Brazilian terrestrial and freshwater ostracods, and in acknowledgement of years of friendship with JH and KM.

Measurements of illustrated specimens. See Table 2 .

Description of male. Valves with suboval shape, with greatest height in front of the middle of the valves. LVi ( Figs 16A, C–D ) with narrow calcified anterior and posterior inner lamella; an inwardly displaced inner list running along the anterior margin, ending in an internal anteroventral tooth, tubercle-sockets displaced along anteroventral and posteroventral margins.

RVi ( Figs 16B, E–F ) with narrow calcified anterior inner lamella and an inwardly displaced inner list along the anterior margin, disappearing in ventral margin; strong marginal tubercles along the anteroventral and posteroventral margins, weakly along middle of ventral margin.

CpRl ( Fig 16G ) with a suboval shape, with greatest height in front of middle; LV overlapping RV along all margins, except in middle of dorsal side, with the greatest overlap in anterior side. CpD ( Fig 16H ) and CpV ( Fig 16I ) with compressed shape, with greatest width slightly behind middle, external surface with shallow pits and setae ( Fig 16J ).

Only the differences with the male of Brasilocypria pea gen. et spec. nov. are described here.

A1 (not illustrated) third segment with two apical setae: ventrally with one short seta almost reaching middle of fourth segment and dorsally with one long seta reaching the tip of fourth segment. Sixth segment with four long apical setae and one short hirsute seta (5x the length of the terminal segment).

A2 (not illustrated) exopodite a small plate with two unequally long setae (the long one ca. 6x the length of the short). Terminal segment with g-seta ca. 1/3 length of y3.

Md-palp (not illustrated) with second segment with one stout hirsute β-seta (ca. 1/2 of the length of the third segment).

Mx1 (not illustrated) with terminal segment of palp apically with three claws and two setae (both ca. 1/2 length of claws).

T1 with protopodite ( Fig 17A ) and endopodite (asymmetrical prehensile palps) ( Figs 17B–C ). Protopodite apically with a group of 12 unequal and hirsute setae, two short smooth a-setae, one smooth b-seta and one long and smooth d-seta (6x length of b-seta), and one long and hirsute seta next to the two a-setae (2x length of d-seta). Rpp ( Fig 17B ) with sharply pointed distal corner of first segment; second segment with curved dorsal margin. Lpp ( Fig 17C ) shorter and narrower, distal segment sickle-shaped, smoothly curved.

T2 (not illustrated) first endopodal segment with one apical hirsute e-seta, almost reaching tip of third endopodal segment. Second endopodal segment with one apical hirsute f-seta, reaching tip of third endopodal segment. Third endopodal segment with one subapical hirsute g-seta, ca. 2x length of terminal segment. Terminal segment with one h3-seta slightly shorter than h1.

CR ( Fig 17D ) well-developed and robust, with long proximal hirsute Sp-seta (ca. 1/2 of ramus), subapically with serrated Gp-claw, apically with long serrated Ga-claw and shorter and smooth Sa-seta.

Hp ( Fig 17E ) with ls and ms both elongated and subequal in length. Ms distally slightly curved, ls distally slightly swollen.

Description of female. Only the differences with the male of Brasilocypria ricardopintoi gen. et spec. nov. are described here.

LVi ( Figs 18A, C–D ) and RVi ( Figs 18B, E–F ) higher than male. CpRl ( Fig 18G ) as in the male; CpD ( Fig 18H ) and CpV wider than male ( Fig 18I ) and external surface with shallow pits and setae ( Fig 18J ).

A1 (not illustrated) third segment ventrally with one seta slightly longer than fourth segment and dorsally with one long seta reaching tip of the fourth segment. Sixth segment with one short hirsute seta (5x length of terminal segment). Terminal segment with one short hirsute seta, ca. 2x length of aesthetasc Ya.

A2 (not illustrated) protopodite with one long apical hirsute seta reaching tip of end claws. Exopodite with one long hirsute seta (reaching tip of the second endopodal segment) and two shorter, unequally long setae (the long one ca. 6x length of the short). Third endopodal segment apically with three claws (G1, G2, G3) and three setae (z1, z2, z3).

T1 ( Fig 19A ) with protopodite apically with a group of 12 unequal and hirsute setae; two short smooth a-setae, one short and smooth b-seta, one long and smooth d-seta (6x length of b-seta), and one long and hirsute seta next to the two a-setae (2x length of d-seta). Endopodite apically with one long and two short setae (one ca. 2/3 length of the long and one 1/2 length of the long).

CR ( Fig 19B ) well-developed and robust, with long proximal Sp-seta (ca. 2/3 of ramus), subapically with serrated Gp-claw, apically with long serrated Ga-claw and short and smooth Sa-seta.

Ecology and distribution. Brasilocypria ricardopintoi gen. et spec. nov. was recorded from only one Brazilian floodplain (Paraná), associated with floating macrophytes. The water temperature was 28°C. The pH was 5.2 and the electrical conductivity was 31.8 μS. cm-1 (see Table 1 ).

Figures

FIGURE 16. Brasilocypria ricardopintoi gen. et spec. nov. ♁ from Alluvial valley of the upper Paraná River floodplain, Banhado Lake (PAR 255). A. LVi (MZUSP 43111). B. RVi (MZUSP 43111). C. LVi, detail of posterior part (MZUSP 43111). D. LVi, detail of anterior part (MZUSP 43111). E. RVi, detail of anterior part (MZUSP 43111), arrow indicates piths fitting teeth in opposing valve. F. RVi, detail of posterior part (MZUSP 43111). G. CpRl (MZUSP 43115). H. CpD (MZUSP 43116). I. CpV (MZUSP 43117). J. CpRl, detail of anterior part showing the surface of Cp (MZUSP 43115). Scale bars:A–B, G–I = 250 μm; C–F, J = 100 μm.Arrow indicates anterior direction.

FIGURE 17. Brasilocypria ricardopintoi gen. et spec. nov. ♁ from Alluvial valley of the upper Paraná River floodplain, Banhado Lake (PAR 255). A. T1 (MZUSP 43111). B. Rpp (MZUSP 43111). C. Lpp (MZUSP 43111). D. CR (MZUSP 43111). E. Hp (MZUSP 43111). Scale bars: A–E = 50 μm.

FIGURE 18. Brasilocypria ricardopintoi gen. et spec. nov. ♀ from Alluvial valley of the upper Paraná River floodplain, Banhado Lake (PAR 255). A. LVi (MZUSP 43112). B. RVi (MZUSP 43112). C. LVi, detail of posterior part (MZUSP 43112). D. LVi, detail of anterior part (MZUSP 43112). E. RVi, detail of anterior part (MZUSP 43112), arrow indicates piths fitting teeth in opposing valve. F. RVi, detail of posterior part (MZUSP 43112). G. CpRl (MZUSP 43120). H. CpD (MZUSP 43121). I. CpV (MZUSP 43122). J. CpV, detail of anterior part showing the surface of Cp (MZUSP 43122). Scale bars: A–B, G–I = 250 μm; C–F = 200 μm; J = 100 μm. Arrow indicates anterior direction.

FIGURE 19. Brasilocypria ricardopintoi gen. et spec. nov. ♀ from Alluvial valley of the upper Paraná River floodplain, Banhado Lake (PAR 255). A. T1 (MZUSP 43112), long seta next to the two a-seta (MZUSP 43119). B. CR (MZUSP 43112). Scale bars: A–B = 50 μm.