Abstract Our knowledge of fossil crustaceans from the tropics has increased considerably during recent decades, thanks to novel findings and the re-examination of museum specimens. However, several previous records have been misidentified, numerous museum specimens have never been reported, and many new discoveries are yet to be published. Here, we present a detailed, up-to-date, and revised checklist for every marine, terrestrial, or freshwater fossil decapod crustacean occurrence from tropical America known to us, including their age, geographic occurrences, and related literature. We recognize the occurrence of at least 32 superfamilies, 69 families, 190 genera, and 415 species of brachyurans (‘true’ crabs), and anomurans (‘false’ crabs, hermit crabs, squat lobsters, and allies), several of them previously unknown. The checklist comprises records from three main geographic regions: 1) northern South America (Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela); 2) Central America and southern North America (Belize, Costa Rica, Honduras, Panama, Mexico, southern and central Florida); and 3) the Caribbean Islands + Bermuda (Anguilla, Antigua, Aruba, Bahamas, Barbados, Bermuda, Bonaire, Cuba, Curaçao, Dominican Republic, The Grenadines, Haiti, Jamaica, Puerto Rico, Saint Bartélemy, Saint Martin, Trinidad). Previous findings, new occurrences, and the revised systematic placement for several problematic/misidentified records, indicate that the fossil record of anomurans and brachyurans in tropical America is more diverse than previously envisioned, with a considerable degree of endemism at the genus- and species-levels.

A new species of the homolid crab, Zygastrocarcinus carolinasensis n. sp., is reported from the Upper Cretaceous (upper Campanian) strata of Coahuila, NE Mexico. Only the anterior part of the ~8 mm wide carapace was preserved in addition to a part of the sternum (sternites 1-6). The sternum is the oldest figured example of a fossil homolid sternum, and also of the entire section of fossil Homoloida. The sternum seems to be similar to extant homolids in general outline, and to an earlier described Eocene homolid. Hitherto, Zygastrocarcinus spp. were only known from the northern part of the USA (Wyoming, Montana, and South Dakota). Thus, the new species extends the geographic range of the genus during the Cretaceous to much of North America. Additionally, this is the second fossil homolid known from Mexico.

Se reporta una nueva especie del cangrejo homólido, Zygastrocarcinus carolinasensis n. sp., en estratos del Cretácico Superior (Campaniano superior) de Coahuila, NE de México. Únicamente se preservó la porción anterior del caparazón de ~8 mm de ancho, además de parte del esternón (esternitos 1-6). El esternón es el ejemplar ilustrado más antiguo para un homólido fósil, así como para toda la sección de los Homoloida fósiles. El esternón es muy parecido a los de homólidos existentes en cuanto a su forma general, y a un homólido del Eoceno descrito previamente. Hasta ahora, se conocían Zygastrocarcinus spp., solamente en la región norte de los EUA (Wyoming, Montana, Dakota del Sur). Por lo tanto, la nueva especie amplía la distribución geográfica del género durante el Cretácico a gran parte de Norteamérica. Además, éste es el segundo homólido fósil reportado para México.

Collections made by Máximo Ruiz de Gaona and Luis Via Boada between 1940 and 1982, from the Albian-Cenomanian reefal limestones at Monte Orobe (Navarra, northern Spain), now housed at the Museo Geológico del Seminario de Barcelona together with newly recovered material, have enabled the recognition of two new primitive crabs. A new genus, Viaia n. gen. (type: Viaia robusta n. sp.), is compared to the closely related Heeia from northern France and southern England; both genera are referred to Viaiidae n. fam., which is characterised by clearly distinguishable features, notably a peculiar cavity at the lateral sides of the carapace. A new genus and species of homolid, Navarrahomola hispanica n. gen., n. sp., is also described and discussed. The two new genera are closely related topodotreme crabs from Albian-Cenomanian levels in southern England and northern France, which confirms the close biogeographic links between these areas.

La recuperación de material para estudio, recolectado por Máximo Ruiz de Gaona y Luis Via Boada entre 1940 y 1982 en las calizas arrecifales del Albiano-Cenomaniano del Monte Orobe (Navarra, norte de España), depositado en la actualidad en el Museo Geológico del Seminario de Barcelona, junto a nuevos materiales disponibles, permite confirmar la presencia de dos interesantes braquiuros primitivos. Un nuevo género, Viaia n. gen. (tipo: Viaia robusta n. sp.), cercano al género Heeia, permite la comparación con material francés e inglés y el registro de una nueva familia, Viaiidae n. fam., basándose en caracteres claramente diferenciadores, en particular una peculiar cavidad en las porciones laterales del caparazón. Se describe y justifica también un nuevo género y especie asignado a la familia Homolidae, Navarrahomola hispanica n. gen. n. sp. Los dos nuevos géneros están estrechamente relacionados con decápodos registrados en capas del Albiano-Cenomaniano del sur Inglaterra y norte de Francia, lo que contribuye a confirmar importantes implicaciones biogeográficas en las áreas mencionadas en ese tiempo.

Recent fieldwork (June 2008) in the reefal limestones near Alsasua, Navarra (northern Spain) has resulted in the discovery of a new species of diogenid hermit crab, Annuntidiogenes wotfi sp. nov., which appears closely related to the type species of the genus, A. ruizdegaonai Fraaije et al., 2008, from Monte Orobe and also of mid-Cretaceous (Albian-Cenomanian) age. The new specimen represents only the third paguroid carapace of Cretaceous age to be described and formally named.

Recientes trabajos de campo (Junio de 2008) en las calizas arrecifales cercanas a la localidad de Alsasua, Navarra (Norte de España) han proporcionado el hallazgo de una nueva especie de cangrejo ermitaño diogénido, Annuntidiogenes worn n. sp., estrechamente relacionado con la especie tipo del género, A. ruizdegaonai Fraaije et al., 2008, del Monte Orobe, en depósitos adscritos al Cretácico medio (Albiense-Cenomaniense). El nuevo ejemplar es el tercer registro de un caparazón de pagúrido preservado en depósitos del Cretácico.