Theriosynoecum quadrinodosum Krommelbein & Weber 1971
Creators: name: Tomé, Maria Emilia
name: Araripe, Rilda
name: Oliveira, David
name: Barreto, Alcina
name: Prado, Ludmila
name: Pedrosa, Flavia
name: Pereira, Priscilla
name: Nascimento, Luiz Ricardo
name: Ng, Christiano
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Ostracoda
Podocopida
Timiriaseviidae
Theriosynoecum
Theriosynoecum quadrinodosum

description: Theriosynoecum cf. quadrinodosum Krömmelbein & Weber, 1971
Fig. 5P–R
1978a Bisulcocypris quadrinodosa —Silva: 1018–20; est. 1, figs. 9–12
2002 Theriosynoecum quadrinodosum — Coimbra et al., Fig. 4:5–6.
2020 Theriosynoecum quadrinodosum — Guzmán-González et al., Fig. 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); 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.
description: Published as part of 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, pp. 535-557 in Zootaxa 5159 (4) on page 552, DOI: 10.11646/zootaxa.5159.4.4, http://zenodo.org/record/6786092