Perissocytheridea poruslinearis, Tomé & Araripe & Oliveira & Barreto & Prado & Pedrosa & Pereira & Nascimento & Ng, 2022

Tomé, Maria Emilia, Araripe, Rilda, Oliveira, David, Barreto, Alcina, Prado, Ludmila, Pedrosa, Flavia, Pereira, Priscilla, Nascimento, Luiz Ricardo & Ng, Christiano, 2022, Early Cretaceous Ostracoda (Crustacea) from south-centralAraripe Basin, Brazil with descriptions of seven new species, Zootaxa 5159 (4), pp. 535-557 : 547

Perissocytheridea poruslinearis sp. nov.

Fig. 4L–O

2022 Perissocytheridea sp.2 —Araripe et al., p 7, fig. 5 (2a–b).

Etymology: Porus (lat.) and linearis (lat.) in reference to the sequence of linear pores that occurs along the dorsal margin.

Holotype: Adult carapace, Nº. DGEO-CTG-UFPE-1520 ( Fig. 4L–O ).

Type locality: Brazil, State of Pernambuco, Municipality of Exu, Santo Antônio section. Coordinates 7° 30’ 06” S and 39° 32’ 36” W .

Type horizon: Santo Antônio section, Araripe Basin. Calcarenite (F-Sl) corresponds to the Romualdo Formation, depth 0.3 m, dated as upper Aptian.

Dimension. Nº. DGEO-CTG-UFPE-1520 ( Fig. 4L–O ); L= (LV) 0.383 / ( RV) 0.320 mm, H= 0.153 mm, and W= 0.142 mm.

Diagnosis: Carapace very small. Presence of pores aligned on the dorsal margin. Reticular ornamentations but more subtle when compared to other species of Perissocytheridea described in this study.

Description: Carapace very small. Subrectangular outline in lateral view. Ventral margin rectilinear on both valves. Dorsal margin rectilinear with drop to posterior end. Anterior margin rounded. Posterior margin sub-triangular tapering to a subtle caudal process, not clear in lateral view but coincides with the greatest length. Greatest height at anterior margin. Left valve slightly overlaps right valve. In the dorsal view, tapering more to anterior to the posterior margin, sharp and short ends. Surface ornamented with smooth primary reticulations and pores spread over the surface, with emphasis on the sequence of three pores along the dorsal margin of each valve. Winged process discrete in the posteroventral margin. Ocular tubercle evident.

Observations. Compared to the other two species of Perissocytheridea , the surface has a very slightly primary reticulated ornamentation and the presence of pores spread on the surface with the set of six sequenced pores on the dorsal margin.

Occurrence and associated fauna. It was recorded in the Santo Antônio section, at the following depths (from base to top): 0.3; 2.25; 2.65; 3.1; 4.05; 3.55 and 5.45 m. Perissocytheridea poruslinearis sp. nov. does not occur with Dicrorygma ( Orthorygma ?) dimorpha.

Stratigraphic distribution. Brazil, Araripe Basin, Romualdo Formation, upper Aptian.

Figures

FIGURE 4. (A–C) Mantelliana speculum sp. nov., (A) nº DGEO-CTG-UFPE-1514, depth 0.3m, dorsal view; (B) nº DGEO- CTG-UFPE-1515, depth 3.10m, right side view; (C) nº DGEO-CTG-UFPE-1516, depth 2.65m, left side view. (D–F) Paracypris undulareventralis sp. nov., (D) nº DGEO-CTG-UFPE-1517, depth 2.65m, dorsal view; (E and F) nº DGEO-CTG-UFPE-1518, depth 0.3m, (E) right side view; (F) left side view. (G–K) Perissocytheridea oculusutilis sp. nov., nº DGEO-CTG-UFPE-1519, depth 3.10m, (G) dorsal view, (H) right side view, (I) left side view, (J) small eye tubercle and detail of the reticular ornamentation (and punctuated surface between the reticles), (K) detail of the small winged process. (L–O) Perissocytheridea poruslinearis sp. nov., nº DGEO-CTG-UFPE-1520, depth 0.3m; (L) left side view; (M) right side view; (N) dorsal view; (O) detail of the dorsal view with presence of six systematic pores. The depth reference is from the bottom to the top. Scale bars are equivalent to 100µm.