The amber of Simojovel de Allende, Chiapas, Mexico, of Late Oligocene-Early Miocene age, has yielded a new flower representing the Meliaceae. The flower of Swietenia miocenica Castañeda-Posadas & Cevallos-Ferriz sp. nov. is characterized by small size; free calyx composed of five glabrous lobes, ciliolated along the margin lobes; corolla composed of five free, contortedly inserted petals with ciliolated margins; cylindrical staminal tube ending in 10 acuminate or toothed accessories and 10 sessile anthers; and a discoid stigma divided in five lobular stigmatic glands. The morphology of S. miocenica is well represented among Meliaceae. Although the new species shares many characters with Swietenia microphylla, small differences in the length and width of petals and the length of staminal tube support its recognition as a new species. The presence of this genus demonstrates the establishment of tropical communities in southern Mexico by the early Miocene and highlights the influence of the northern hemisphere flora on the extant neotropical flora of the area.

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We describe a new fossil wood from the El Bosque Formation (Eocene) in Chiapas, southern Mexico. It has a combination of features found in the Anacardiaceae, including distinct growth rings, diffuse porosity, vessels solitary and in radial multiples of 2–3, simple perforation plates, medium to large alternate intervessel pits, vessel-ray parenchyma pits rounded and elongate with reduced borders, septate and non-septate fibers, axial parenchyma scanty paratracheal, vasicentric, apotracheal diffuse, Kribs heterogeneous rays type IIA, and multiseriate rays with radial canals. The mosaic of features of this wood supports the erection of a new genus, Bosquesoxylon Pérez-Lara, Castañeda-Posadas et Estrada-Ruiz. This new genus of anacardiaceous fossil wood extends our knowledge of this family’s history and offers hints on the possible relationships with floras from other localities worldwide, especially North America and Asia.

The San José de Gracia Quarry, located within the Municipality of Molcaxac, southern Puebla, Mexico, is a new paleontological site discovered about a decade ago. This paper is the first formal scientific contribution of this site. The quarry occupies an area no larger than the two hectares that is exploited for commercial purposes, where slabs are extracted from a marine sequence of cream-brown strata of poorly carbonated clays, with centimetric thickness. Although the upper and lower limits of this sequence are not known; the characteristic lithology and fossil content do not correspond with those of the regional geological units previously reported. Although the fossil association recovered from the San José de Gracia Quarry is composed mostly of fish remains; it also contains ammonites, belemnites, inoceramids, indeterminate ostreids, reptiles and few plant remains. In this work, the first fossil fish remains from this locality are described, including representatives of Enchodus and clupeid both previously known from Mexico; as well as the first record of Dercetis and Xenyllion from this country. In addition, a yaguarasaurine mosasaur is also reported. Based on its fossil content and its lithology, the fossil-bearing strata of the San José de Gracia quarry can be possibly referred to the Mexcala Formation (Morelos-Guerrero Basin) of Turonian age.