FIGURE 1. Map of the vicinity of Palenque including División del Norte and Belisario Domínguez quarries. The yellow areas show the outcrops of Paleocene marine strata identified here as Tenejapa-Lacandón unit (based on Servicio Geológico Mexicano, 2006a, 2006b).
FIGURE 2. General views of the División del Norte ( 1 ) and Belisario Domínguez quarries ( 2 ). 3, A nodule in situ at División del Norte (between the black arrows). 4, Strata laminated in Belisario Domínguez quarry. 5, Gray silicified bands within the marl strata in a Paleocene non fossiliferous quarry near Palenque. 6, Plant or algae remains remains of Belisario Domínguez quarry.
FIGURE 3. 1 , General view of the specimen IGM 4547, an anguilliform fish from the Paleocene marine strata at Belisario Domínguez quarry, Municipality of Palenque, Chiapas, Mexico. 2 , Close up of the posterior part of the trunk and caudal fin. 3 , Close-up of the region of the head and anterior part of the trunk. Scale bars equal 10 mm. Abbreviations: af, anal fin; br, branchistegal rays; cf, caudal fin; df, dorsal fin; op, opercle; pfr, pectoral fin rays; numbers show the position of each vertebrae.
FIGURE 4. 1 , General view of the specimen IGM 4548, a clupeid from the Paleocene marine strata at División del Norte, Municipality of Palenque, Chiapas, Mexico. 2 , Close-up of the pectoral girdle. 3 , Close-up of the caudal region. Abbreviations: as, abdominal scutes; pcl, posclethra; pu1+un1, pural centra 1 and uroneural 1 fused to each other; numbers show the position of ribs and vertebrae. Scale bar equals 10 mm.
FIGURE 5. Specimen IGM 4549, Phareodus sp. from the Paleocene marine strata of División del Norte quarry, Municipality of Palenque, Chiapas, Mexico. Scale bar equals 20 mm. Abbreviations: alj, articulation of lower jaw; op, opercle; pfr 1, first pectoral fin ray; psp, parasphenoid; arrows in the tail enclose the caudal principal fin rays.
FIGURE 6. Specimen IGM 4550, a “Serranidae” fish from the Paleocene marine strata at División del Norte quarry, Municipality of Palenque, Chiapas, Mexico. Scale bar equals 10 mm. Abbreviations: afr, anal fin ray; afs, anal fin spine; dfr, dorsal fin rays; dfs, dorsal fin spine; mx, maxilla; op, opercle; par, parapophysis (in the vertebra 10); pcfr, pectoral fin rays; pmx, premaxilla; pvb, pelvic bone; pvfr, pelvic fin rays; pvfs, pectoral fin spine; smx, supramaxilla; numbers show the position of the vertebrae.
FIGURE 7. Close-up and line drawing of the anterior dorsal region of the body of IGM 4550, a “Serranidae” fish from the Paleocene marine strata at División del Norte quarry, Municipality of Palenque, Chiapas, Mexico. Scale bar equals 10 mm. Abbreviations: dfs, dorsal fin spine; dpt, dorsal pterygiophopre; ns, neural spine; sn, supraneurals; numbers show the position of the vertebrae.
FIGURE 8. Specimen IGM 4551, Pycnodus sp. from the Paleocene marine strata of División del Norte quarry, Municipality of Palenque, Chiapas, Mexico. Scale bar equals 20 mm. Abbreviations: cls, cloacal scale; cp, caudal peduncle; dmfe, dermocranial fenestra; drs, dorsal ridge scales; ms, modified bar-like scales; papr, parietal process; partt, prearticular teeth; vks, ventral keel scales; vt, vomer teeth.
FIGURE 9. Paleocene map showing the distribution of localities with osteichthyan fossils (based on Weems, 1998; Arratia et al., 2004) (black and white concentric circles), the distribution of the craters of the multiple asteroid impacts in the mass extinction event of the Cretaceous-Tertiary boundary (black and white concentric stars), and the distribution of land and main marine sedimentary domains around Palenque (based on Meneses-Rocha, 2001, figure 12e).
