Biodiversity Data Journal :
Data Paper (Biosciences)
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Corresponding author: Carlos E. Paz-Ríos (carlepaz@uacam.mx), Atahualpa Sosa-López (atahsosa@uacam.mx)
Academic editor: Felipe Ottoni
Received: 01 Mar 2021 | Accepted: 13 May 2021 | Published: 21 May 2021
© 2021 Carlos Paz-Ríos, Atahualpa Sosa-López, Yassir Torres-Rojas, Julia Ramos-Miranda, Rodolfo del Río-Rodríguez
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Paz-Ríos CE, Sosa-López A, Torres-Rojas YE, Ramos-Miranda J, del Río-Rodríguez RE (2021) Fish species richness in the Terminos Lagoon: An occurrence data compilation of four sampling campaigns along a multidecadal series. Biodiversity Data Journal 9: e65317. https://doi.org/10.3897/BDJ.9.e65317
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Here we present an occurrence dataset that contributes to the knowledge of tropical fish distribution in coastal habitats from the Terminos Lagoon Flora and Fauna Protection Area, one of the largest lagoon ecosystems in the Gulf of Mexico. Fish are high biomass keystone species in the Terminos Lagoon which provide socio-economic and ecosystem services. An initiative in 1980 was carried out to systematically sample the fish community of Terminos Lagoon for an annual cycle; the effectiveness of its results led to replicate in the lagoon the same sampling design for three more campaigns in 1998, 2010 and 2016. Constituted as a Flora and Fauna Protection Area in 1994, the Terminos Lagoon has received many efforts to inventory its biodiversity, particularly on the fish community since the 70s; however, these studies did not have consistent survey protocols, nor the longevity of the present study, which was over four decades.
A total of 141 fish species, belonging to 90 genera, 49 families, 20 orders and two classes are presented in this study. Information on fish species occurrence data is provided corresponding to the Terminos Lagoon coastal ecosystem, southern Gulf of Mexico, assembled from four time periods at 1980, 1998, 2010 and 2016. The records form part of a consistently homogeneous database compilation, mostly derived from the research programme's sampled material on tropical fishery resources of the “Instituto de Ecologia, Pesquerias y Oceanografia del Golfo de Mexico (EPOMEX)”. The current dataset represents the first and most comprehensive online open-access source of information concerning the fish community occurring along and wide of the Terminos Lagoon ecosystem, with 1,249 data records and a total count of 48,717 organisms. Data are available through the Ocean Biodiversity Information System (OBIS).
biodiversity, Campeche, coastal lagoon, estuary, fish occurrence, fishery resource, Gulf of Mexico
Terminos Lagoon is a tropical coastal aquatic system with high biodiversity and abundant natural resources (
The fish community from the Terminos Lagoon has been sampled extensively in space and time by virtue of the academic initiatives of the research programme on tropical fishery resources from the “Instituto de Ecologia, Pesquerias y Oceanografia del Golfo de Mexico (EPOMEX)”, forming a wide range of biological and environmental data, useful for monitoring the lagoon ecological status. Within the framework of this sampling effort, information on the fish community has been obtained systematically and consistently. Data was collected during the years 1980, 1998, 2010 and, more recently, in 2016. The primer for this long-term study programme highlights the research of Dr. Alejandro Yáñez Arancibia, who was one of the most renowned academics in Mexico on coastal ecology and conservation, contributing and compiling the first compendium on natural resources and ecological processes of the Terminos Lagoon (
The extensive work of multiple institutions helped to provide further a wide variety of information on biological, ecological and socioeconomic aspects of the ichthyofauna in the Terminos Lagoon (e.g.
Recognised in 1994 as a Flora and Fauna Protection Area, the Terminos Lagoon (along with the Campeche continental shelf) maintains numerous commercially important fisheries which employ thousands of people in the southern Gulf of Mexico. However, the historical trend in the fish abundance and biomass in Terminos Lagoon might suggest an overall decrease in catch volumes (
The objective of the present study is to document the fish species richness by sharing information on a species occurrence dataset in the Terminos Lagoon, one of the largest and most productive lagoon-estuarine ecosystems in the Gulf of Mexico. To achieve this objective, species occurrence data from four methodologically consistent sampling campaigns were assembled, covering four decades of ecological surveys along and wide of the Lagoon.
Terminos Lagoon Fish Occurrence.
Atahualpa Sosa López, Julia Ramos Miranda, Yassir Edén Torres Rojas, Domingo Flores Hernández, Francisco Gómez Criollo, Luis Alejandro Yáñez Arancibia, Ana Laura Lara Domínguez, Luis Amado Ayala Pérez, Hernán Álvaréz Guillén, Sebastien Villèger, David Mouillot, Rodolfo Enrique del Río Rodríguez, Carlos Enrique Paz Ríos.
Terminos Lagoon shows a high spatiotemporal variability in its biophysical characteristics; hence, four zones have been determined by ecological studies to characterise different environmental conditions and fish assemblages. The project design is aimed to provide species occurrence data by zone, so four coordinates were represented as different centroids, determined from three to five sampling sites per zone for representing each one of these. In the different sampling campaigns, the same methodological protocols for collecting fish samples was carried out through the four time periods.
The resources to undertake research in the Lagoon have been received from diverse academic projects: “Mecanismos de produccion en Ecosistemas Lagunares Costeros, Laguna de Terminos, Mexico y Laguna de Arcachon, Francia, UNAM-CONACYT-Universidad de Burdeaux QCMACFR-001698”; Evaluacion del camaron blanco (Penaeus setiferus) y de las comunidades nectonicas de la Laguna de Terminos-Sonda de Campeche, Mexico: interaccion de los impactos ambientales y pesqueros, SISIERRA ALIM/97”; “Ecologia del Paisaje y Diagnostico Ambiental del ANP de la Laguna de Terminos, P/SISIERRA 2000706030”; “Long-term effects of environmental changes on the nekton biodiversity and the functioning of tropical estuaries, BIODIVNEK ANR-CONACYT C0004-2009-01-000000000111465”; and “Analisis de δ13C y δ18O en otolitos de peces marinos presentes en el Area de Proteccion de Flora y Fauna Laguna de Terminos, Campeche: indicadores del cambio climatico, FONSEC SEMARNAT-CONACYT 000000000263401”.
The dataset contains information on fish collected (juvenile and adult stages) in four different campaigns: the first one in February 1980 – January 1981, the second one in February 1998 – January 1999, the third one in November 2010 – October 2011 and the fourth one in September 2016 – August 2017. In each sampling campaign, the lagoon was visited in a N-S direction, as well as an E-W direction in order to increase the chances of capturing the greatest species diversity, taking samples from different environmental conditions, such as habitats dominated by seagrasses or sand beds and near to river mouths or inlets connected to the sea with different salinity concentrations. Each sampling campaign encompassed an annual period that covered the three regional weather seasons: dry, rainy, winter storms.
Fish samples were collected with a shrimp trawl net. This fishing gear was an active method consisting of a 5-m long net with a mouth opening diameter of 2.5 m and mesh size of 19 mm. One net per site was trawled at a speed of ~ 4.6 km h-1 (2.5 knots) for 12 min, covering an area of 2000 m2 each trawl. Fish samples were placed in plastic bags and stored in ice during the sampling campaigns. In the laboratory, fish were sorted and identified to the species category. Organisms from the last three sampling campaign were transferred to 70% ethanol and provisionally stored at the fisheries laboratory of the EPOMEX Institute.
Fish species were sorted and identified to the species taxonomical category, using specialised literature, such as guides and keys for identification, for example,
Exploratory analysis of the fish occurrence data
Species richness: The total number of species, with regards to time, was evaluated by the sampling effort through the four sampling campaigns, using a species accumulation curve with interpolation-extrapolation of the Hill number for incidence data (
Temporal pattern: Temporal changes in composition and abundance (root square transformation) through the time of commercially important species, according to
The Terminos Lagoon is situated in the Mexican littoral zone of Campeche (Fig.
Location of sampling sites and the four centroids per zone in the Terminos Lagoon, Campeche, Mexico. Zones based on classification by
18°40' N and 18°90' N Latitude; 92°00' W and 91°20' W Longitude.
The dataset contains occurrence records from organisms belonging to the class Actinopteri and Elasmobranchii (
Taxonomic classification of the fish community from the Terminos Lagoon, Campeche, Mexico. * Commercially important species after
Class | Order | Family | Species | 1 | 2 | 3 | 4 |
Elasmobranchii | Myliobatiformes | Dasyatidae | Dasyatis hastata (DeKay, 1842) | ● | |||
*Hypanus americanus (Hildebrand & Schroeder, 1928) | ● | ● | |||||
~Hypanus sabinus (Lesueur, 1824) | ● | ● | ● | ● | |||
Gymnuridae | Gymnura micrura (Bloch & Schneider, 1801) | ● | ● | ||||
Potamotrygonidae | Styracura schmardae (Werner, 1904) | ● | ● | ||||
Urotrygonidae | Urobatis jamaicensis (Cuvier, 1816) | ● | ● | ● | ● | ||
Rhinopristiformes | Rhinobatidae | Pseudobatos lentiginosus (Garman, 1880) | ● | ● | |||
Actinopteri | Acanthuriformes | Ephippidae | *~Chaetodipterus faber (Broussonet, 1782) | ● | ● | ● | ● |
Lobotidae | *~Lobotes surinamensis (Bloch, 1790) | ● | |||||
Anguilliformes | Muraenidae | Gymnothorax nigromarginatus (Girard, 1858) | ● | ||||
Gymnothorax saxicola Jordan & Davis, 1891 | ● | ||||||
Ophichthidae | Ophichthus gomesii (Castelnau, 1855) | ● | ● | ||||
Aulopiformes | Synodontidae | Synodus foetens (Linnaeus, 1766) | ● | ● | ● | ● | |
Batrachoidiformes | Batrachoididae | ~Opsanus beta (Goode & Bean, 1880) | ● | ● | ● | ● | |
Porichthys porosissimus (Cuvier, 1829) | ● | ● | ● | ||||
Beloniformes | Belonidae | ~Strongylura notata (Poey, 1860) | ● | ||||
Hemiramphidae | ~Chriodorus atherinoides Goode & Bean, 1882 | ● | ● | ||||
Blenniiformes | Blenniidae | Hypleurochilus geminatus (Wood, 1825) | ● | ||||
Labrisomidae | Paraclinus fasciatus (Steindachner, 1876) | ● | |||||
Carangiformes | Achiridae | ~Achirus lineatus (Linnaeus, 1758) | ● | ● | ● | ● | |
~Trinectes maculatus (Bloch & Schneider, 1801) | ● | ● | ● | ● | |||
Bothidae | Bothus ocellatus (Agassiz, 1831) | ● | |||||
Carangidae | *Caranx crysos (Mitchill, 1815) | ● | ● | ||||
*~Caranx hippos (Linnaeus, 1766) | ● | ● | ● | ● | |||
~Caranx latus Agassiz, 1831 | ● | ||||||
Caranx ruber (Bloch, 1793) | ● | ||||||
*Chloroscombrus chrysurus (Linnaeus, 1766) | ● | ● | ● | ● | |||
Hemicaranx amblyrhynchus (Cuvier, 1833) | ● | ● | ● | ||||
~Oligoplites saurus (Bloch & Schneider, 1801) | ● | ● | ● | ||||
*Selene setapinnis (Mitchill, 1815) | ● | ● | |||||
Selene vomer (Linnaeus, 1758) | ● | ● | ● | ● | |||
*Trachinotus carolinus (Linnaeus, 1766) | ● | ||||||
Trachinotus falcatus (Linnaeus, 1758) | ● | ||||||
Trachinotus goodei Jordan & Evermann, 1896 | ● | ||||||
Centropomidae | *~Centropomus parallelus Poey, 1860 | ● | ● | ||||
*~Centropomus poeyi Chávez, 1961 | ● | ||||||
*~Centropomus undecimalis (Bloch, 1792) | ● | ||||||
Cynoglossidae | *Symphurus civitatum Ginsburg, 1951 | ● | ● | ||||
~Symphurus plagiusa (Linnaeus, 1766) | ● | ● | ● | ● | |||
Paralichthyidae | Ancylopsetta quadrocellata Gill, 1864 | ● | ● | ||||
~Citharichthys spilopterus Günther, 1862 | ● | ● | ● | ● | |||
Etropus crossotus Jordan & Gilbert, 1882 | ● | ● | ● | ● | |||
Syacium gunteri Ginsburg, 1933 | ● | ||||||
Polynemidae | Polydactylus octonemus (Girard, 1858) | ● | ● | ● | ● | ||
Sphyraenidae | Sphyraena barracuda (Edwards, 1771) | ● | |||||
Cichliformes | Cichlidae | ~Mayaheros urophthalmus (Günther, 1862) | ● | ● | ● | ● | |
Clupeiformes | Clupeidae | *~Brevoortia gunteri Hildebrand, 1948 | ● | ||||
~Dorosoma anale Meek, 1904 | ● | ||||||
~Dorosoma petenense (Günther, 1867) | ● | ● | |||||
*Harengula clupeola (Cuvier, 1829) | ● | ||||||
*~Harengula jaguana Poey, 1865 | ● | ● | ● | ● | |||
*Opisthonema oglinum (Lesueur, 1818) | ● | ● | ● | ● | |||
*Sardinella aurita Valenciennes, 1847 | ● | ||||||
Engraulidae | ~Anchoa hepsetus (Linnaeus, 1758) | ● | ● | ● | ● | ||
Anchoa lamprotaenia Hildebrand, 1943 | ● | ● | |||||
Anchoa lyolepis (Evermann & Marsh, 1900) | ● | ||||||
~Anchoa mitchilli (Valenciennes, 1848) | ● | ● | ● | ● | |||
Cetengraulis edentulus (Cuvier, 1829) | ● | ● | ● | ● | |||
Cyprinodontiformes | Fundulidae | ~Lucania parva (Baird & Girard, 1855) | ● | ||||
Elopiformes | Elopidae | Elops saurus Linnaeus, 1766 | ● | ||||
Gobiiformes | Eleotridae | ~Eleotris pisonis (Gmelin, 1789) | ● | ||||
Gobiidae | ~Bathygobius soporator (Valenciennes, 1837) | ● | |||||
~Gobionellus oceanicus (Pallas, 1770) | ● | ● | ● | ● | |||
Gobiosoma longipala Ginsburg, 1933 | ● | ||||||
Mugiliformes | Mugilidae | *~Mugil cephalus Linnaeus, 1758 | ● | ||||
*~Mugil curema Valenciennes, 1836 | ● | ● | |||||
Perciformes | Scaridae | Nicholsina usta (Valenciennes, 1840) | ● | ● | |||
Scorpaenidae | Scorpaena brasiliensis Cuvier, 1829 | ● | |||||
Scorpaena plumieri Bloch, 1789 | ● | ● | ● | ||||
Triglidae | Prionotus beanii Goode, 1896 | ● | |||||
Prionotus carolinus (Linnaeus, 1771) | ● | ● | ● | ||||
Prionotus martis Ginsburg, 1950 | ● | ||||||
Prionotus punctatus (Bloch, 1793) | ● | ● | |||||
Prionotus rubio Jordan, 1886 | ● | ● | |||||
Prionotus scitulus Jordan & Gilbert, 1882 | ● | ● | ● | ● | |||
Prionotus tribulus Cuvier, 1829 | ● | ● | ● | ||||
Gerreidae | ~Diapterus auratus Ranzani, 1842 | ● | ● | ● | |||
~Diapterus rhombeus (Cuvier, 1829) | ● | ● | ● | ● | |||
~Eucinostomus argenteus Baird & Girard, 1855 | ● | ● | ● | ● | |||
~Eucinostomus gula (Quoy & Gaimard, 1824) | ● | ● | ● | ● | |||
~Eucinostomus melanopterus (Bleeker, 1863) | ● | ● | ● | ||||
*~Eugerres plumieri (Cuvier, 1830) | ● | ● | ● | ● | |||
Haemulidae | Anisotremus virginicus (Linnaeus, 1758) | ● | |||||
*~Conodon nobilis (Linnaeus, 1758) | ● | ||||||
Haemulon aurolineatum Cuvier, 1830 | ● | ● | ● | ||||
*Haemulon bonariense Cuvier, 1830 | ● | ● | ● | ● | |||
*Haemulon plumierii (Lacepède, 1801) | ● | ● | ● | ● | |||
*~Orthopristis chrysoptera (Linnaeus, 1766) | ● | ● | ● | ● | |||
Lutjanidae | *~Lutjanus analis (Cuvier, 1828) | ● | ● | ● | |||
*Lutjanus apodus (Walbaum, 1792) | ● | ||||||
*~Lutjanus griseus (Linnaeus, 1758) | ● | ● | ● | ● | |||
*Lutjanus synagris (Linnaeus, 1758) | ● | ● | ● | ● | |||
*Ocyurus chrysurus (Bloch, 1791) | ● | ||||||
Sciaenidae | *~Bairdiella chrysoura (Lacepède, 1802) | ● | ● | ● | ● | ||
*Bairdiella ronchus (Cuvier, 1830) | ● | ● | ● | ● | |||
Corvula batabana (Poey, 1860) | ● | ||||||
*~Cynoscion arenarius Ginsburg, 1930 | ● | ● | ● | ● | |||
*~Cynoscion nebulosus (Cuvier, 1830) | ● | ● | ● | ● | |||
*Cynoscion nothus (Holbrook, 1848) | ● | ● | ● | ||||
*Menticirrhus americanus (Linnaeus, 1758) | ● | ● | ● | ● | |||
*Menticirrhus littoralis (Holbrook, 1847) | ● | ||||||
Menticirrhus saxatilis (Bloch & Schneider, 1801) | ● | ● | ● | ● | |||
~Micropogonias furnieri (Desmarest, 1823) | ● | ● | |||||
*~Micropogonias undulatus (Linnaeus, 1766) | ● | ● | ● | ● | |||
Odontoscion dentex (Cuvier, 1830) | ● | ||||||
~Stellifer lanceolatus (Holbrook, 1855) | ● | ● | ● | ● | |||
Serranidae | Diplectrum bivittatum (Valenciennes, 1828) | ● | |||||
*Diplectrum formosum (Linnaeus, 1766) | ● | ● | |||||
Epinephelus itajara (Lichtenstein, 1822) | ● | ||||||
*Mycteroperca bonaci (Poey, 1860) | ● | ● | |||||
Sparidae | *~Archosargus probatocephalus (Walbaum, 1792) | ● | ● | ● | ● | ||
Archosargus rhomboidalis (Linnaeus, 1758) | ● | ● | ● | ● | |||
Calamus penna (Valenciennes, 1830) | ● | ||||||
*~Lagodon rhomboides (Linnaeus, 1766) | ● | ● | ● | ||||
Stenotomus caprinus Jordan & Gilbert, 1882 | ● | ||||||
Scombriformes | Stromateidae | Peprilus paru (Linnaeus, 1758) | ● | ● | |||
Trichiuridae | *Trichiurus lepturus Linnaeus, 1758 | ● | ● | ● | ● | ||
Siluriformes | Ariidae | *~Ariopsis felis (Linnaeus, 1766) | ● | ● | ● | ● | |
*Bagre marinus (Mitchill, 1815) | ● | ● | ● | ● | |||
*~Cathorops melanopus (Günther, 1864) | ● | ● | ● | ● | |||
Syngnathiformes | Dactylopteridae | Dactylopterus volitans (Linnaeus, 1758) | ● | ||||
Syngnathidae | Hippocampus erectus Perry, 1810 | ● | ● | ● | ● | ||
Hippocampus zosterae Jordan & Gilbert, 1882 | ● | ||||||
Syngnathus floridae (Jordan & Gilbert, 1882) | ● | ||||||
~Syngnathus fuscus Storer, 1839 | ● | ||||||
Syngnathus louisianae Günther, 1870 | ● | ● | ● | ||||
~Syngnathus scovelli (Evermann & Kendall, 1896) | ● | ● | ● | ● | |||
Tetraodontiformes | Diodontidae | Chilomycterus schoepfii (Walbaum, 1792) | ● | ● | ● | ● | |
Monacanthidae | Aluterus schoepfii (Walbaum, 1792) | ● | ● | ● | |||
Monacanthus ciliatus (Mitchill, 1818) | ● | ● | |||||
Stephanolepis hispida (Linnaeus, 1766) | ● | ● | ● | ● | |||
Ostraciidae | Acanthostracion quadricornis (Linnaeus, 1758) | ● | ● | ● | ● | ||
Tetraodontidae | Lagocephalus laevigatus (Linnaeus, 1766) | ● | ● | ● | |||
Sphoeroides greeleyi Gilbert, 1900 | ● | ● | ● | ● | |||
Sphoeroides maculatus (Bloch & Schneider, 1801) | ● | ||||||
Sphoeroides marmoratus (Lowe, 1838) | ● | ||||||
Sphoeroides nephelus (Goode & Bean, 1882) | ● | ● | ● | ● | |||
Sphoeroides pachygaster (Müller & Troschel, 1848) | ● | ||||||
Sphoeroides parvus Shipp & Yerger, 1969 | ● | ● | |||||
Sphoeroides spengleri (Bloch, 1785) | ● | ● | ● | ● | |||
~Sphoeroides testudineus (Linnaeus, 1758) | ● | ● | ● | ● |
Species richness: The species accumulation curve showed a weak slope at the observed species richness (141 spp.) as a function of the number of sampling units through the four periods of study (Fig.
Temporal pattern: As part of the fish community recorded for the Terminos Lagoon, 45 spp. are considered commercially important (Fig.
1 February 1980 – 17 August 2017.
Creative Commons Attribution Non Commercial (CC-BY-NC) 4.0 License.
The dataset presents an occurrence data sheet with 28 columns including information for 1,249 records (
Column label | Column description |
---|---|
eventID | An identifier for the set of information associated with an Event (something that occurs at a place and time). |
parentEventID | An event identifier for the super-event which is composed of one or more sub-sampling events. |
samplingProtocol | The name of, reference to, or description of the method or protocol used during an Event. |
eventDate | The date-time or interval during which an Event occurred. |
identifiedBy | A list (concatenated and separated) of names of people, groups or organisations who assigned the Taxon to the subject. |
waterbody | The name of the water body in which the Location occurs. |
country | The name of the country or major administrative unit in which the Location occurs. |
countryCode | The standard code for the country in which the Location occurs. |
decimalLatitude | The geographic latitude (in decimal degrees, using the spatial reference system given in geodeticDatum) of the geographic centre of a Location. |
decimalLongitude | The geographic longitude (in decimal degrees, using the spatial reference system given in geodeticDatum) of the geographic centre of a Location. |
geodeticDatum | Spatial reference system (SRS) upon which the geographic coordinates given in decimalLatitude and decimalLongitude are based. |
occurrenceID | An identifier for the Occurrence (as opposed to a particular digital record of the occurrence). In the absence of a persistent global unique identifier, construct one from a combination of identifiers in the record that will most closely make the occurrenceID globally unique. |
individualCount | The number of individuals represented present at the time of the Occurrence. |
occurrenceStatus | A statement about the presence or absence of a Taxon at a Location. |
preparations | A list (concatenated and separated) of preparations and preservation methods for a specimen. |
associatedReferences | A list (concatenated and separated) of identifiers (publication, bibliographic reference, global unique identifier, URI) of literature associated with the Occurrence. |
institutionCode | The name (or acronym) in use by the institution having custody of the object(s) or information referred to in the record. |
datasetName | The name identifying the dataset from which the record was derived. |
basisOfRecord | The specific nature of the data record. |
dataGeneralisations | Actions taken to make the shared data less specific or complete than in its original form. Suggests that alternative data of higher quality may be available on request. |
scientificNameID | An identifier for the nomenclatural (not taxonomic) details of a scientific name. |
scientificName | The full scientific name (with authorship and date information if known. => add to scientificNameAuthorship). |
kingdom | The full scientific name of the kingdom in which the taxon is classified. |
phylum | The full scientific name of the phylum or division in which the taxon is classified. |
class | The full scientific name of the class in which the taxon is classified. |
order | The full scientific name of the order in which the taxon is classified. |
family | The full scientific name of the family in which the taxon is classified. |
taxonRank | The taxonomic rank of the most specific name in the scientificName. |
Ethics statement: The authors declare that they have no conflict of interest. Applicable international and national guidelines for the care and use of animals were followed by the authors. All necessary permits for sampling and observational field studies have been obtained by the authors from the competent authorities.
To Ana Carolina Peralta (Universidad Simon Bolivar, Venezuela) for her valuable assistance for managing the data into GBIF and OBIS; to the journal's reviewers for their comments/suggestions to improve the paper. We thank the kind assistance of Jon Fong (California Academy of Science) for assembling the taxonomic classification. CEPR thank the CONACYT postdoctoral scholarship.