# Cintura Formation

The Cintura Formation is a geologic formation in the northeastern Sonora of Arizona and Mexico. It preserves fossils dating back to the Cretaceous period.

## Description

The Cintura Formation is divided into 3 stratigraphic members which represent deltaic depositional elements: the basal Marquechi Member, medial San Marcos Member and the uppermost San Juan Member. The delta is thought to have prograded southward and have an immediate source to its north based on paleocurrents and provenance data.

## Fossil content

Dinoflagellates :
| Genus | Species | Presence | Material | Notes | Images |
| Oligosphaeridium | O. sp. | Base of the Marquechi Member. | Dinoflagellate cysts. | | |
Plants :
| Genus | Species | Presence | Material | Notes |
| cf. Acanthotriletes | cf. A. varispinosus | Base of the Marquechi Member. | Spores. | |
| Alisporites | A. sp. | Base of the Marquechi Member. | Pollen grains. | |
| Araliaephyllum | A. silvapinedae | Near the town of Cabullona, Sonora, Mexico. | A trilobed leaf. | A laurale. |
| Baculatisporites | B. sp. | Base of the Marquechi Member. | Spores. | |
| Cicatricosisporites | C. hallei | Base of the Marquechi Member. | Spores. | A schizaeacean fern. |
| Cicatricosisporites | C. sp. | Base of the Marquechi Member. | Spores. | A schizaeacean fern. |
| Classopollis | C. spp. | Base of the Marquechi Member. | Pollen grains. | A cheirolepidiaceaen conifer. |
| Clavatipollenites | C. tenellis | Base of the Marquechi Member. | Pollen grains. | |
| Cycadopites | C. sp. | Base of the Marquechi Member. | Pollen grains. | |
| Deltoidospora | D. sp. | Base of the Marquechi Member. | Spores. | |
| Ephedripites | E. sp. | Base of the Marquechi Member. | Pollen grains. | |
| Exesipollenites | E. tumulus | Base of the Marquechi Member. | Pollen grains. | |
| Inaperturopollenites | I. sp. | Base of the Marquechi Member. | Pollen grains. | A conifer. |
| Isoetites | I. sp. | San Juan Member. | Leaves. | An isoetalean. |
| Leptolepidites | L. sp. 1 | Base of the Marquechi Member. | Spores. | A fern. |
| Leptolepidites | L. sp. 2 | Base of the Marquechi Member. | Spores. | A fern. |
| Leptolepidites | L. sp. 3 | Base of the Marquechi Member. | Spores. | A fern. |
| Osmundacites | O. wellmanii | Base of the Marquechi Member. | Spores. | |
| Ovoidites | O. parvus | Base of the Marquechi Member. | Spores. | An aquatic zygnematale. |
| Patellasporites | P. sp. | Base of the Marquechi Member. | Spores. | |
| Perinopollenites | P. sp. | Base of the Marquechi Member. | Pollen grains. | |
| Peromonolites | P. allensis | Base of the Marquechi Member. | Spores. | A fern. |
| Pityosporites | P. sp. | Base of the Marquechi Member. | Pollen grains. | |
| Plicatella | P. potomacensis | Base of the Marquechi Member. | Spores. | |
| Raistrickia | R. sp. | Base of the Marquechi Member. | Spores. | |
| Retimonocopites | R. sp. 1 | Base of the Marquechi Member. | Pollen grains. | |
| Retimonocopites | R. sp. 2 | Base of the Marquechi Member. | Pollen grains. | |
| Spheripollenites | S. sp. | Base of the Marquechi Member. | Pollen grains. | |
| Taxodiaceaepollenites | T. hiatus | Base of the Marquechi Member. | Pollen grains. | |
| Todisporites | T. minor | Base of the Marquechi Member. | Spores. | |
| Triporoletes | T. sp. cf. T. radiatus | Base of the Marquechi Member. | Spores. | A bryopsid. |
| Tucanopollis | T. sp. | Base of the Marquechi Member. | Pollen grains. | |
| Undulatisporites | U. undulapolus | Base of the Marquechi Member. | Spores. | |
| Undulatisporites | U. sp. | Base of the Marquechi Member. | Spores. | |