Theriosynoecum cf. quadrinodosum Krömmelbein & Weber, 1971

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 : 552

publication ID	https://doi.org/ 10.11646/zootaxa.5159.4.4
publication LSID	lsid:zoobank.org:pub:D3D2D54E-4B22-45FC-9904-FBB8BEF2E601
DOI	https://doi.org/10.5281/zenodo.6794778
persistent identifier	https://treatment.plazi.org/id/31296775-CE68-FFE6-86B7-FE759E3BF9FC
treatment provided by	Plazi
scientific name	Theriosynoecum cf. quadrinodosum Krömmelbein & Weber, 1971
status

Treatment

Fig. 5P–R View FIGURE 5

1978a Bisulcocypris quadrinodosa —Silva: 1018–20; est. 1, figs. 9–12

2002 Theriosynoecum quadrinodosum — Coimbra et al., Fig. 4 View FIGURE 4 :5–6.

2020 Theriosynoecum quadrinodosum — Guzmán-González et al., Fig. 5 View FIGURE 5 (b).

2022 Theriosynoecum quadrinodosum — Araripe et al., p 7, fig. 5 (11a–b).

Illustrated material. Juvenile shell, Nº. DGEO-CTG-UFPE-1528. Illustrated material from the Santo Antônio section (3.1 m).

Dimension. Nº. DGEO-CTG-UFPE-1528 ( Fig. 5P–R View FIGURE 5 ); L= (LV) 0.603/ ( RV) 0.688 mm, W= 0.365 mm and H= 0.352 mm.

Comparison. Material compared to Theriosynoecum silvai ( Silva, 1978a) (Nº DGEO-CTG-UFPE-1970 e DGEO-CTG-UFPE-1166), described and deposited by Tomé et al. (2014) in the Ivan de Medeiros Tinoco Microfossils Collection of the Paleontology Laboratory of the Federal University of Pernambuco. It was observed that the specimen found in the present study corresponds to a juvenile specimen and it has nodules in the posterior margin that differentiate it from the species deposited in the mentioned collection.

Occurrence and associated fauna. It was recorded in the Santo Antonio section, just in the depths (from base to top): 0.3 m. T. cf. quadrinodosum is associated with the species of ostracods: P. angulata , P. micropapillosa , D. grandiensis , D. cf. minuta, Mantelliana speculum sp. nov. and Mongolianella aptianensis sp. nov.

Observations. So far four species belonging to the genus Theriosynoecum Branson (1936) have been recorded in the Aptian/Albian: Theriosynoecum silvai ( Silva, 1978a) , Theriosynoecum munizi ( Silva, 1978a) , Theriosynoecum colini Do Carmo et al., 2013 and Theriosynoecum guzzoia Do Carmo et al., 2013 . Regarding the first two, Tomé et al. (2014) placed T. munizi in synonymy as being a young form of T. silvai . The specimen observed in the present manuscript does not resemble the forms found for this interval. However, it corresponds to a young male of Theriosynoecum quadrinodosum , with characteristic nodules in the posterior margin. This species is recorded in interior basins in Northeast Brazil, of Jurassic age ( Silva et al. 1978a; Coimbra et al. 2002; Guzmán-González et al. 2020), so if the range of the T. quadrinodosum is confirmed, it would be recorded as far back as the Aptian. What made the authors leave this species in confer is the fact that they found only a single, unique specimen among all the samples.

Stratigraphic distribution. Brazil, Araripe Basin, Formação, Brejo Santo, Jurassic ( Coimbra et al. 2002). Jatobá Basin, Aliança Formation, Jurassic ( Guzmán-González et al. 2020). Araripe Basin, Romualdo Formation, upper Aptian.