JOURNAL OF CRUSTACEAN BIOLOGY, 36(6), 776-784, 2016 THE PRIMARY FRESHWATER CRABS OF GUATEMALA (DECAPODA: BRACHYURA: PSEUDOTHELPHUSIDAE), WITH COMMENTS ON THEIR CONSERVATION STATUS Ingo S. Wehrtmann 1,2,∗, Célio Magalhães 3, and Mónica N. Orozco 4 1 Museo de Zoología, Escuela de Biología, Universidad de Costa Rica, 11501-2060 San José, Costa Rica 2 Unidad de Investigación Pesquera y Acuicultura (UNIP), Centro de Investigación de Ciencias del Downloaded from https://academic.oup.com/jcb/article-abstract/36/6/776/2735695 by guest on 19 May 2020 Mar y Limnología (CIMAR), Universidad de Costa Rica, 11501-2060 San José, Costa Rica 3 Instituto Nacional de Pesquisas da Amazônia, Av. André Araújo 2936, 69067-375 Manaus, Amazonas, Brazil 4 Centro de Estudios Atitlán, Universidad del Valle de Guatemala, campus Altiplano, Km 137 Caserío Xolbé, Cantón El Tablón, Sololá, Guatemala ABSTRACT The freshwater crabs of the family Pseudothelphusidae Ortmann, 1893 are restricted to the Neotropics and many species have an elevated risk of extinction. The majority of pseudothelphusids is considered to be data-deficient, which impedes the assessment of their vulnerability levels. More than 50% of pseudothelphusids are endemic to Guatemala, and half of the species are categorized as data-deficient. In order to update and broaden our knowledge of the freshwater crab fauna of Guatemala, several surveys were carried out from 2014 to 2015, combined with the examination of collections of freshwater crabs of Guatemala deposited in several museums. A total of 55 specimens comprising six pseudothelphusid species were collected. The most common species were Potamocarcinus armatus H. Milne Edwards, 1853 (20% of the material identified to the species level), Phrygiopilus ibarrai (Pretzmann, 1978), Raddaus bocourti (A. Milne-Edwards, 1866), and Potamocarcinus magnus Rathbun, 1896 (14.5% each). The collection of the Universidad del Valle de Guatemala consisted of 57 lots with 69 individuals of nine pseudothelphusid species; predominant species were R. bocourti (61.7% of all identified lots) and P. magnus (20.5%). The following species are reported here as new records for Guatemala: Elsalvadoria zurstrasseni (Bott, 1956), Raddaus mertensi (Bott, 1956), and two undescribed species (Phrygiopilus sp., Zilchia sp.). Almost half of the 17 freshwater crab species (including the two undescribed) are either data-deficient or not yet assessed, and 65% (11 species) are endemic to Guatemala. Conservation strategies are urgently needed to preserve the integrity of the sites and habitats occupied by freshwater crabs, along with studies aiming to fill the gap of the data-deficient species. KEY WORDS: biodiversity, Central America, conservation status, faunal surveys, Neotropical region DOI: 10.1163/1937240X-00002478 INTRODUCTION one-fifth of all the world’s brachyurans or true crabs (Cum- Freshwater habitats are among the most species-rich and en- berlidge and Ng, 2009). The study by Cumberlidge et al. dangered ecosystems in the world (Revenga and Kura, 2003; (2009) on the conservation status of freshwater crabs re- Dudgeon et al., 2006; Abell et al., 2008). Although freshwa- vealed that one-sixth of all assessed species have an ele- ter represents an insignificant portion of the world’s water vated risk of extinction; however, given that almost half of and just 0.8% of the earth’s surface, it harbors an extraordi- the species lack information on vulnerability, that assess- nary wealth of species, roughly 7% of all described species ment is an underestimation of the true risk level. According worldwide (Darwall et al., 2008). This species diversity is to Cumberlidge et al. (2009), Trichodactylidae and Pseu- threatened by numerous factors, mainly associated with an- dothelphusidae (both restricted to the Neotropics) have the thropogenic activities such as increasing demand for drink- highest threat. Cumberlidge et al. (2014) assessed the con- ing water, dam construction, river flow modification, and servation status of the freshwater crabs in the Neotropics and pollution (Revenga and Kura, 2003; Dudgeon et al., 2006; concluded that 34% of pseudothelphusids have an elevated Abell et al., 2008; Darwall et al., 2008). As a consequence, risk of extinction, and 56% of the species of this family are the extinction risk for freshwater species is higher than for data-deficient. their terrestrial counterparts (Collen et al., 2014). The primary freshwater crab fauna of Central America Primary, or true, freshwater crabs are heterotreme bra- is fairly well studied, and is composed mainly by repre- chyurans that live in freshwater, semi-terrestrial, or terres- sentatives of Pseudothelphusidae with only a few species trial habitats, and that reproduce by direct development, of Trichodactylidae in Nicaragua and Panama (e.g., Smal- lacking free-living larval stages (Yeo et al., 2008; Cumber- ley, 1970; Pretzmann, 1972, 1978, 1980; Rodriguez, 1982; lidge and Ng, 2009). Primary freshwater brachyuran crabs Magalhães and Türkay, 1996, 2008; Rodriguez and Magal- are represented by more than 1300 species and comprise hães, 2005; Lara et al., 2013; Magalhães et al., 2013). Costa ∗ Corresponding author; e-mail: [email protected]; [email protected] © The Crustacean Society, 2016. Published by Brill NV, Leiden DOI:10.1163/1937240X-00002478 WEHRTMANN ET AL.: FRESHWATER CRABS OF GUATEMALA 777 Rica, with 15 species (Magalhães et al., 2015), and Panama, the studies of H. Milne Edwards (1853) and Rodriguez with 14 species (Cumberlidge et al., 2014), are the Central (2001), and only recently Wehrtmann et al. (2014) clarified American countries with the highest diversity of pseudothel- the species identity of the freshwater crabs caught by local phusids, followed by Guatemala with 12 species (Cumber- fishermen of Lake Atitlán. Practically all published infor- lidge et al., 2014). Endemic pseudothelphusid species are mation concerns taxonomic aspects, and virtually nothing is relatively common in the Central American region, espe- known about the biology and ecology of these species. cially in Panama (12), Guatemala (nine) (Cumberlidge et al., There is an urgent need to update and broaden our knowl- 2014), and Costa Rica (six) (Magalhães et al., 2015). edge of the freshwater crabs of Guatemala, especially con- Guatemala is a fairly small country (108,889 km2)lo- sidering that more than 50% of the Guatemalan pseudothel- cated in northern Central America, bordering with Mex- phusids are endemic to the country and half of which are categorized as “data-deficient” (Cumberlidge et al., 2014). ico, Belize, Honduras, and El Salvador. The country har- Here we report the findings of recent surveys carried out bors a diverse freshwater crab fauna, but the taxonomic across Guatemala as well as preliminary results of the ex- Downloaded from https://academic.oup.com/jcb/article-abstract/36/6/776/2735695 by guest on 19 May 2020 status of several species is uncertain because species and amination of collections that contain specimens of freshwa- subspecies have been described and/or synonymized by dif- ter crabs from this country, particularly from a relatively ferent authors (Smalley, 1970; Pretzmann, 1972, 1978, 1980; large collection deposited at the Universidad del Valle de Rodriguez, 1982, 1992). In a recent revision (Cumberlidge Guatemala, Guatemala City. et al., 2014), six genera and 12 species were reported for Guatemala, including three cave-dwelling pseudothel- MATERIALS AND METHODS phusid crabs. Rodriguez (1982) considered an additional five We visited numerous locations in Guatemala during 2014 (January and species for Guatemala as incertae sedis. Studies of the fresh- July) and 2015 (August) (Fig. 1). All licenses required for research, water crabs of Guatemala were mostly undertaken between collection, transportation, and export of specimens to the Museo de Fig. 1. Location of sampling stations in Guatemala in 2014 (January and July) and 2015 (August). This figure is published in colour in the online edition of this journal, which can be accessed via http://booksandjournals.brillonline.com/content/journals/1937240x. 778 JOURNAL OF CRUSTACEAN BIOLOGY, VOL. 36, NO. 6, 2016 Zoología at the Universidad de Costa Rica were obtained from the San José, Costa Rica (UCR-MZ), and Field Museum of Natural History, Consejo Nacional de Areas Protegidas de Guatemala (CONAP). Crabs were Chicago (FMNH). One of us (CM) examined most of the material in 12 collected during daytime by lifting rocks directly in or close to streams and of these institutions, whereas information about material housed in six other water bodies. In some cases, local people collaborated by collecting other institutions were obtained online from the Global Biodiversity In- crabs in larger streams, diving at depths of up to 2 m. The collected formation Facility (GBIF portal; http://www.gbif.org). Primary types of all specimens were stored in individual plastic bags with 70% ethyl alcohol. 24 taxa described or recorded from Guatemala are housed in MNHN (12 At each sampling location, we recorded the altitude and coordinates with taxa), USNM (five taxa), Forschungsinstitut und Naturmuseum Sencken- a GPS (Garmin Foretrex 401, Olathe, KS) and photographed (Nikon berg, Frankfurt a.M. (SMF) (three taxa), Naturhistorisches Museum Wien, Coolpix P7000) the sampling sites where the crabs were obtained. Voucher Vienna (NHMW) (two taxa), and The Natural History Museum, London specimens were deposited in the Museo de Zoología, Universidad de (NHM) and Naturhistorisches Museum