1
Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
Freshwater crab research in Costa Rica: past, present and future
Ingo S. Wehrtmann1,2; https://orcid.org/0000-0002-6826-7938
Célio Magalhães3,4; https://orcid.org/0000-0003-4858-2575
1. Museo de Zoología of the Centro de Investigación en Biodiversidad y Ecología Tropical (CIBET), Universidad de Costa
Rica, San José, Costa Rica; ingo.wehrtmann@ucr.ac.cr (*Correspondence)
2. Centro de Investigación en Ciencias del Mar y Limnología (CIMAR), Universidad de Costa Rica, San José, Costa Rica.
3. Laboratory of Bioecology and Crustacean Systematics (LBSC), Department of Biology, Faculty of Philosophy, Sciences
and Letters at Ribeirão Preto (FFCLRP), University of São Paulo (USP); São Paulo, Brazil; celiomag@usp.br
4. Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus, Brazil.
Received 15-III-2024. Corrected 30-XVIII-2024. Accepted 24-I-2025.
ABSTRACT
Introduction: Freshwater crabs occur in tropical and subtropical regions around the world and are due to their
large biomass an important component in ecosystem processes. In Central America, Panama and Costa Rica
stand out for their high diversity with 17 and 15 of freshwater crab species, respectively.
Objective: Here we present an analysis of the freshwater crab research in Costa Rica and provide suggestions for
future research topics related to these macro-invertebrates.
Methods: The analysis is based on publications dealing with freshwater crab research in Costa Rica. We included
only publications that included specimens collected in Costa Rica; on the contrary, publications, which only
mentioned freshwater crab species from Costa Rica were not included.
Results: The number of publications increased especially during the last two decades, reaching a total of 35
contributions. The history of freshwater crab research in Costa Rica might be divided into the following three
periods: (1) Period I: pre-1900, the discovery phase as the start of freshwater crab research by the description
of the first species from Costa Rica; (2) Period II: 1900–2000 when, after a long intermission, taxonomic stud-
ies on the freshwater crab fauna were resumed; and (3) Period III: post-2000 characterized by initiating studies
including the ecology and molecular phylogeny of freshwater crabs while continuing the biodiversity assessment
of these decapods.
Conclusions: Our knowledge about freshwater crabs in Costa Rica has increased considerably, especially during
the last decades; however, information about many aspects of the life history and ecology of these invertebrates
remains fragmentary or simply absent. Future research areas might include studies about ecology and behavior,
the impact of climate change and other stressors (e.g., pollution, deforestation, habitat loss, and invasive spe-
cies) on the existing populations as well as their role as intermediate hosts for metacercariae of the trematode
Paragonimus spp. Finally, we stress the need to maintain and continue the collection of freshwater crabs in the
Universidad de Costa Rica.
Key words: biodiversity, decapod crustaceans, Pseudothelphusidae, conservation assessment, Central America.
RESUMEN
Investigaciones sobre cangrejos de agua dulce en Costa Rica: pasado, presente y futuro
Introducción: Los cangrejos de agua dulce se encuentran en regiones tropicales y subtropicales de todo el
mundo y debido a su gran biomasa, son un componente importante en los procesos ecosistémicos. En América
https://doi.org/10.15517/rev.biol.trop..v73iS1.63633
SUPPLEMENT
2Revista de Biología Tropical, ISSN: 2215-2075 Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
INTRODUCTION
The majority of the currently known more
than 6 700 species of brachyuran crabs can
be found in marine environments. However,
almost 1 400 crab species are so-called true or
primary freshwater crabs (Cumberlidge, 2016;
Yeo et al., 2008), which share the following
characteristics: (1) they have adopted freshwa-
ter, semi-terrestrial or terrestrial modes of life,
(2) are completely independent of marine envi-
ronments, and (3) reproduce by direct develop-
ment, which means that they are lacking any
free-living larval stage, hatching directly as
juveniles (Cumberlidge & Ng, 2009; Yeo et al.,
2008). In the present contribution, the term
“freshwater crabs” refers to true or primary
freshwater crabs.
Freshwater crabs occur in tropical and sub-
tropical regions around the world and most of
them live associated with a variety of freshwa-
ter bodies (Yeo et al., 2008), including flowing
and standing waters covering a range of water
quality, but also in caves (for Neotropics, e.g.
Álvarez & Villalobos, 1998; Cumberlidge et
al., 2014; Rodríguez & Herrera, 1994). Others,
however, are terrestrial species, which can typi-
cally be found away from permanent freshwater
sources, occupying for example water pools
in tree holes (e.g., Bayliss, 2002; Cumberlidge
& Vannini 2004; Grinang et al., 2015) and
leaf axils (e.g., Wehrtmann et al., 2016a). Due
to their large biomass, freshwater crabs are
important players in ecosystem processes (e.g.,
Abdallah et al., 2004; Masese et al. 2014; Yang
et al., 2020a, Yang et al., 2020b) and interact
with their environment as predators and prey
(Wehrtmann et al., 2019).
Freshwater habitats are among the most
endangered ecosystems in the world (Abell
et al., 2008; Dudgeon et al., 2006; Revenga &
Kura, 2003) and its species diversity is threat-
ened by a variety of factors, mainly associ-
ated with anthropogenic activities, which have
resulted in an elevated extinction rate of fresh-
water species (Collen et al., 2014), including
freshwater crabs (Cumberlidge et al., 2014). A
recent assessment of freshwater crab species in
Central, Panamá y Costa Rica destacan por su gran diversidad, con 17 y 15 especies de cangrejos de agua dulce,
respectivamente.
Objetivo: Aquí presentamos un análisis de las investigaciones sobre cangrejos de agua dulce en Costa Rica y
ofrecemos sugerencias para futuros temas de investigación relacionados con estos macroinvertebrados.
Métodos: El análisis se basa en las publicaciones que tratan sobre la investigación de cangrejos de agua dulce
en Costa Rica. Se incluyeron sólo publicaciones que incluían especímenes recolectados en Costa Rica; por el
contrario, no se incluyeron publicaciones que sólo mencionan especies de cangrejos de agua dulce de Costa Rica.
Resultados: El número de publicaciones aumentó especialmente durante las dos últimas décadas, alcanzando
en la actualidad un total de 35 contribuciones. La historia de la investigación sobre los cangrejos de agua dulce
en Costa Rica podría dividirse en los siguientes tres períodos: (1) Período I: pre-1900, la fase de descubrimiento
como inicio de la investigación del cangrejo de agua dulce por la descripción de las primeras especies de Costa
Rica; (2) Período II: 1900-2000 cuando, tras un largo periodo de ausencia de publicaciones, se retomaron los
estudios taxonómicos sobre la fauna de cangrejos de agua dulce; y (3) Período III: post-2000, caracterizado por el
inicio de estudios que incluyen la ecología y filogenia molecular de los cangrejos de agua dulce mientras que se
continúa con la evaluación de la biodiversidad de estos decápodos.
Conclusiones: Nuestro conocimiento sobre los cangrejos de agua dulce en Costa Rica ha aumentado considera-
blemente, especialmente durante las últimas décadas; sin embargo, la información sobre muchos aspectos de la
historia de vida y la ecología de estos invertebrados sigue siendo fragmentaria o simplemente ausente. Futuras
áreas de investigación podrían incluir estudios sobre ecología y comportamiento, impacto del cambio climático
y otros factores de estrés (por ejemplo, contaminación, deforestación, pérdida de hábitat y especies invasoras)
sobre sus poblaciones, así como su papel como hospedadores intermediarios de metacercarias del tremátodo
Paragonimus spp.. Finalmente, enfatizamos la necesidad de mantener y continuar la colección de cangrejos de
agua dulce en la Universidad de Costa Rica.
Palabras clave: biodiversidad, crustáceos decápodos, Pseudothelphusidae, evaluación de la conservación,
América Central.
3
Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
Colombia, the country with the highest species
number reported in the Neotropics, revealed
an alarming increase of threatened species
from 26 % in 2008, to 34 % in 2015, to 62 % in
2018 (Acevedo-Alonso & Cumberlidge, 2021).
Moreover, an appropriate assessment of the
conservation status of Neotropical crab species
is still hampered by the high number of species
classified as “Data Deficient”, since knowledge
about their distributions, biology, and ecology
is still quite incipient (Cumberlidge et al., 2014;
Wehrtmann et al., 2016b). Proposing appropri-
ate measures for the conservation and manage-
ment of this group of crustaceans depends on
detailed knowledge of aspects of their biology
and ecology.
On a worldwide scale, east and southeast-
ern Asia harbor the highest diversity of fresh-
water crabs, followed by the Neotropics with
311 species in two families: Trichodactylidae
and Pseudothelphusidae (Cumberlidge et al.,
2014). Diversity hotspots in the Neotropics
are Colombia and Mexico (Cumberlidge et
al., 2014), while Panama and Costa Rica stand
out for its high diversity in Central America
with 17 and 15 species, respectively (Mag-
alhães et al., 2015).
Costa Rica is well known as a biodiversity
hotspot with approximately 3.6 % of the total
expected world’s diversity (Kohlmann et al.,
2010; Mittermeier et al., 2014). The country
has abundant and diverse freshwater ecosys-
tems, which harbor a great biological diver-
sity, particularly freshwater macroinvertebrates
(Springer et al., 2014). The hydrological com-
ponent comprises 34 water basins, 320 wetland
areas and 510 lacustrine systems, including
natural systems such as coastal lagoons, lakes,
and lagoons as well as those of antropogenic
origin (e.g., reservoirs and dams for hydro-
electric power plants) (see Coto-Pacheco et al.,
2005; Springer et al., 2014). All these aquatic
environments, ranging from sea level up to
3500 m. a. s. l. (Umaña et al., 1999), represent
potential habitats for freshwater crabs.
Freshwater crab research in Costa Rica
Fig. 1 provides an overview about the
production of freshwater crab publications of
Costa Rica. This time line might be divided
into the following three periods: (1) Period I:
pre-1900, the discovery phase as the start of
freshwater crab research by the description of
Fig. 1. Accumulative production of publications about freshwater crabs from Costa Rica. We considered only publications
that included specimens collected in Costa Rica; on the contrary, publications that only mentioned freshwater crab species
from Costa Rica were not considered.
4Revista de Biología Tropical, ISSN: 2215-2075 Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
the first species from Costa Rica; (2) Period
II: 1900–2000 when, after a long intermission,
taxonomic studies on the freshwater crab fauna
were resumed; and (3) Period III: post-2000
characterized by initiating studies including the
ecology and molecular phylogeny of freshwater
crabs while continuing the biodiversity assess-
ment of these decapods.
Period I: The incipient status of natural
history studies in Costa Rica in the 19th cen-
tury meant that, as was customary in Latin
America at the time, specimens collected in
the country were usually sent to European and
North American museums for study by experts
in the respective taxonomic groups (Lobo et
al., 2021). Scientists who pioneered biological
studies in Costa Rica in the late 19th century,
whether foreigners like Charles W. Richmond,
Paul Biolley, and Henri Pittier, or locals like
José Fidel Tristán Fernández and José Cástulo
Zeledón Porras (Lobo et al., 2021; Quirós, 2013;
Quirós, 2022), sent their collections of freshwa-
ter crabs to the National Museum of Natural
History, Washington D.C. (USA), where they
were properly studied by Mary Jane Rathbun,
one of the great carcinologists at the turn of the
19th and 20th centuries. In three publications,
Rathbun (Rathbun, 1893; Rathbun, 1896; Rath-
bun, 1898) authored eleven (10 still considered
valid today) of the 20 nominal taxa (currently
valid or not) of this group ever described and
recorded from Costa Rica. With this, she is the
most prolific author regarding the description
of species of the Costa Rican freshwater crab
fauna. Table 1 lists in chronological order in
which all 20 nominal species were described
from, or currently occurring in, Costa Rica, and
provides additional information about their
taxonomic authorities, the country of the type
locality, the reference in which the first record
of their occurrence in Costa Rica was made, as
well as the institutional collection where the
type material is deposited.
In her first publication, Rathbun (1893)
described Potamocarcinus nicaraguensis based
on specimens from Costa Rica and Nicaragua
collected in the Rio San Juan watershed but
she chose Nicaragua as the type locality (Rath-
bun, 1905). In this paper, she also described
Pseudothelphusa richmondi (= Potamocarcinus
richmondi) and Pseudothelphusa colombianus
(= Ptychophallus colombianus), from Nicara-
gua and Panama, respectively. Both species
were later recorded also from Costa Rica: Po.
richmondi by Rathbun (1905), Smalley (1964),
Pretzmann (1972), and Magalhães et al. (2015),
and Pt. colombianus by Lara et al. (2013) and
Magalhães et al. (2015). In a subsequent work,
dedicated exclusively to species from Costa
Rica (Rathbun, 1896), she described two new
species: Pseudothelphusa magna (= Potamo-
carcinus magnus) (Fig. 2A) and Pseudothel-
phusa tristani (= Ptychophallus tristani), the
latter named in honor of its collector, the Costa
Rican José Fidel Tristán. It was in her third
work (Rathbun, 1898), however, that she added
the largest number of species described by a
single author to the Costa Rican freshwater
crab fauna. Following the taxonomic concept of
that time, all species were included in the genus
Pseudothelphusa (but currently transferred to
other genera): Ps. exilipes (= Ptychophallus exili-
pes) (Fig. 2B), Ps. montana (= Pt. montanus),
Ps. tumimanus (= Pt. tumimanus), Ps. agrestis
(= Achlidon agrestis), Ps. pittieri (= Allacanthus
pittieri, named after Henri Pittier), and Ps. con-
vexa (currently a synonym of Pt. montanus).
Period II: Studies of Costa Rican fresh-
water crabs went through a long intermission
during the first half of the 20th century. The
only notable exception was the publication of
Rathbun’s seminal three-part monograph on
the systematics of world freshwater crabs, all of
which were then grouped under a single fam-
ily, Potamonidae. The second part (Rathbun,
1905), which dealt with the then subfamily
Pseudothelphusinae, did not add any new taxon
to the Costa Rican fauna but expanded the
geographic distribution of some of the species.
A new surge of interest in the study of
the river crabs from Costa Rica began in the
mid-1960s when Smalley (1964), one of the
first authors to systematically use gonopodal
features as an essential tool in the taxonomic
5
Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
studies of these crabs, proposed the erection
of four subgenera within the genus Pseudothel-
phusa to classify the diversity of Costa Rican
species: Ps. (Achlidon), Ps. (Allacanthos), Ps.
(Megathelphusa), and Ps. (Ptychophallus), in
addition to provide new records of occurrence
for several species. Except for Megathelphusa,
all other subgenera were later raised to generic
level.
Table 1
Nominal species of pseudothelphusid freshwater crabs (valid and synonyms, listed in chronological order they appeared in
the taxonomic literature) described from, or currently occurring in, Costa Rica, their taxonomic authorities, country of the
type locality, reference of the first record in Costa Rica, and repository collection of the type material.
Taxa Taxonomic
authority Type Locality First record in CR Type material
Ptychophallus colombianus (Rathbun, 1893) Panama Lara et al. (2013) USNM
Potamocarcinus richmondi (Rathbun, 1893) Nicaragua Rathbun (1905) USNM
Potamocarcinus nicaraguensis Rathbun, 1893 Nicaragua Rathbun (1893) USNM
Potamocarcinus magnus (Rathbun, 1896) Costa Rica
(Unknown)
USNM
Ptychophallus tristani (Rathbun, 1896) Costa Rica
(San José)
USNM
Ptychophallus exilipes (Rathbun, 1898) Costa Rica
(Unknown)
USNM
Achlidon agrestis (Rathbun, 1898) Costa Rica
(Cartago)
USNM
Ptychophallus montanus (Rathbun, 1898) Costa Rica
(San José)
USNM
Ptychophallus tumimanus (Rathbun, 1898) Costa Rica
(Cartago)
USNM
Pseudothelphusa convexa
(= Ptychophallus montanus)
Rathbun, 1898 Costa Rica
(Puntarenas)
USNM
Allacanthos pittieri (Rathbun, 1898) Costa Rica
(Puntarenas)
USNM
Ptychophallus paraxantusi (Bott, 1968) Costa Rica
(Puntarenas)
MNHN
Ptychophallus campylus
(= Ptychophallus tristani)
Pretzmann, 1968 Costa Rica
(Unknown)
NHMW
Ptychophallus costaricensis Villalobos, 1974 Costa Rica
(San José)
UCR-MZ
Ptychophallus (Pt.) tumimanus
ingae (= Ptychophallus tumimanus)
Pretzmann, 1978 Costa Rica
(Puntarenas)
NHMW
Achlidon puntarenas Hobbs III, 1991 Costa Rica
(Puntarenas)
USNM
Ptychophallus uncinatus Campos & Lemaitre,
1999
Panama Lara et al. (2013) USNM
Ptychophallus barbillaensis
(= Ptychophallus uncinatus)
Rodríguez &
Hedström, 2000
Costa Rica
(Limón)
UCR-MZ
Ptychophallus osaensis
(= Ptychophallus paraxantusi)
Rodríguez, 2001 Costa Rica
(Puntarenas)
USNM
Allacanthos yawi Magalhães, Lara &
Wehrtmann, 2010
Costa Rica
(Puntarenas)
UCR-MZ
Abbreviations: CR: Costa Rica; MNHN: Muséum national d’Histoire naturelle, Paris; NHMW: Naturhistorishes Museum
Wien, Vienna; UCR-MZ, Museo de Zoología de la Universidad de Costa Rica, San José; USNM, National Museum of Natural
History, Smithsonian Institution, Washington, D.C.
6Revista de Biología Tropical, ISSN: 2215-2075 Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
After the Rathbun’s (Rathbun, 1893; Rath-
bun, 1896; Rathbun, 1898) publications, new
species from Costa Rica were only described
again in 1968 by European carcinologists. In
that year, Pretzmann, who had elevated Pty-
chophallus to full generic status somewhat
earlier (Pretzmann, 1965), described Ptycho-
phallus (Ptychophallus) campylus collected
from an undetermined locality in Costa Rica
(Pretzmann, 1968). Bott (1968), without recog-
nizing the new generic arrangement proposed
by Pretzmann (1965), described Pseudothelphu-
sa (Ptychophallus) paraxantusi based on speci-
mens from Costa Rica that were erroneously
assigned by Rathbun (1898), Rathbun (1905)
and Smalley (1964) to Pseudothelphusa xantusi,
a species from Mexico currently considered
as incertae sedis (Rodriguez, 1982). Schmitt
(1969) presented a more detailed illustration of
the male first gonopod of Achlidon agrestis to
complement the description of the then subge-
nus provided by Smalley (1964).
The first description of a new species
published by a Costa Rican carcinologist was
made by Carlos R. Villalobos and appeared in
the Revista de Biología Tropical in 1974. Based
on material he collected in southwestern Costa
Rica, Villalobos (1974) described Ptychophallus
Fig. 2. A. Potamocarcinus magnus (Rathbun, 1896), male, syntype, USNM 19049, habitus, dorsal view; B. Ptychophallus exilipes
(Rathbun, 1898), male, USNM 39089, habitus, dorsal view; C. Ptychophallus costaricensis Villalobos, 1974, male (carapace
width 34.8 mm) and female (carapace width 26.5 mm), paratypes, TMNH 6408, habitus, dorsal view; D. Ptychophallus
uncinatus Campos & Lemaitre, 1999, male, collected in Veragua, Atlantic slope of Costa Rica; habitus, dorsal view.
7
Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
costaricensis (Fig. 2C). He also verified the
extent of the distribution of Po. nicaraguensis in
Costa Rica and compared the intraspecific vari-
ability between populations of this species from
the San Carlos River basin and those from the
Nicaragua lakes (Villalobos & Burgos, 1974).
Pseudothelphusa puntarenas (= Achlidon
puntarenas) was described by Hobbs III (1991),
who considered it the first cavernicolous crab
from Costa Rica, as it was based on specimens
collected in the Emus Cave, Puntarenas Prov-
ince, in the southern portion of the country.
This species was later found also in epigean
environments (Magalhães et al., 2015). Ptycho-
phallus montanus, although it does not exhibit
characteristic morphological adaptations for
underground life, was also found in caves from
this same region (Hobbs III, 1993).
The other two taxa introduced as new are
presently treated as junior synonyms of pre-
viously described species: Pretzmann (1978)
described Ptychophallus (Pt.) tumimanus ingae
(= Pt. tumimanus), and Rodríguez & Hed-
ström (2000) introduced Ptychophallus barbil-
laensis, which was synonymized by Magalhães
et al. (2015) under Ptychophallus uncinatus
(Fig. 2D), a species originally described from
Panama by Campos & Lemaitre (1999) but later
found also in the Grande de Térraba River basin
in southern Costa Rica (Lara et al., 2013).
During this period, it is worth mentioning
that the revisional studies by Pretzmann (1972)
and Rodriguez (1982) on the systematics of the
pseudothelphusid crabs as well as the studies
by Bott (1967) and Pretzmann (1980) on the
material from Central America added relevant
information on the taxonomy and distribution
of the species from Costa Rica.
Period III: This phase is the most produc-
tive period with a total of (so far) 17 publica-
tions. Although the taxonomic work continued
during this period with the description of a new
species, Ptychophallus osaensis (= Pt. paraxan-
tusi) by Rodríguez (2001) and Allacanthos yawi
by Magalhães et al. (2010), as well as a study on
the diversity and distribution of the river crabs
inhabiting the Grande de Térraba River basin
(Lara et al., 2013), and a revision of Costa Rican
freshwater crabs that included all representa-
tives of the genus Ptychophallus (see Magalhães
et al., 2015), there has been a clear shift of the
research focus: practically for the first time,
studies included and centered around the ecol-
ogy of the freshwater crabs. For example, Rigler
(2012) and Garlick-Ott (2017) studied behav-
ioral aspects of populations of Po. magnus and
Ptychophallus spp., respectively, that inhabit
the cloud forest in Monteverde (Puntarenas),
whereas Corajod (2015) investigated sexual
dimorphism and habitat preferences of fresh-
water crabs occurring in this same area. Other
studies experimented in the field with frog clay
models of different colors (Baringer, 2019; Wil-
link et al., 2014) and concluded that crab pre-
dation did not depend on frog coloration. Field
observations of Pt. uncinatus revealed not only
cannibalism, but also showed that different
specimens of this species were preying upon an
insect larva, a frog, and a lizard, while a spider
of the family Ctenidae was feeding on a speci-
men of Pt. uncinatus (see Wehrtmann et al.,
2019). On the other hand, Ramírez-Fernández
& Fernández-Vargas (2020) reported the first
record of the crab-eating rat, Ichthyomys twee-
dii, from Costa Rica (presumably preying on
pseudothelphusid crabs at the location where
it was found in southern Costa Rica), and Yang
et al. (2020a) and Yang et al. (2020b) quanti-
fied the effects of pseudothelphusid crabs on
leaf breakdown concluding that these crabs
are a significant element in detrital processing
in headwater stream. Recently, Deleva et al.
(2023) reviewed the status of the knowledge of
the cave-dwelling fauna of Costa Rica, which
included notes on freshwater crabs. All these
studies provided novel information about the
role of freshwater crabs in Neotropical freshwa-
ter ecosystems.
Phase III also represents the beginning of
molecular studies including freshwater crab
species occurring in Costa Rica. The first study,
published by Poettinger et al. (2016), analyzed
the phylogenetic relationships among Neo-
tropical freshwater crabs of the Pseudothelphu-
sidae, focusing on the taxonomic position of
8Revista de Biología Tropical, ISSN: 2215-2075 Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
Ptychophallus and related genera. More recent-
ly, Álvarez et al. (2020) presented a revision of
the higher taxonomy of Neotropical freshwater
crabs of the family Pseudothelphusidae, using
both multigene and morphological analyses.
Outlook
International collaboration has been a
key factor for the progress of freshwater crab
research during the last two decades. Sev-
eral projects funded by the Universidad de
Costa Rica and Consejo Nacional de Recto-
res (CONARE) allowed to establish networks
among Latin American researchers of fresh-
water crabs, which resulted not only in numer-
ous publications, but also in an exchange of
students, especially with the Universidad de
São Paulo, Brazil. These collaborations need
to be continued as part of multidisciplinary
studies, which always should include inter-
ested students to foster (1) the development
of a future generation of scientists focusing on
or at least including freshwater crabs and (2)
the establishment of (international) research
groups studying different aspects of freshwater
crabs in the Neotropics.
The taxonomic diversity of freshwater
crabs in Costa Rica has been well studied,
especially during the last years. Fig. 3 shows the
geographic distribution of sampling locations
where freshwater crabs were found in Costa
Rica. Although this map might not include
absolutely all reports, it certainly reveals not
only the sample distribution of freshwater crabs
in Costa Rica, but also reflects the efforts made
to obtain freshwater crab samples from differ-
ent areas in Costa Rica. Despite this geographic
coverage, it does not mean that the freshwater
crab inventory in Costa Rica is completed and
that no new records of (eventually new) spe-
cies can be expected. Therefore, it is strongly
recommended to continue freshwater crab sur-
veys, especially in areas where sampling efforts
have been limited or absent (see Fig. 3).
The collection of freshwater crabs in the
Museo de Zoología of the Universidad de
Costa Rica, MZUCR, has been and will be an
extremely valuable source of information for
everybody interested in these macroinverte-
brates. Considering the concept of collections-
based science in the 21st century (see Funk,
2018), it is of utmost importance to keep
managing these collections adequately and to
count on qualified human resources for the
maintenance of both the deposited specimens
and the corresponding database. The deposited
specimens can be used for the extraction of
DNA material, which in turn allows us to revise
the identification of the samples. Additionally,
the analyses of molecular material from pre-
served crabs will provide valuable data regard-
ing the evolution of characters and modes of
speciation. The collection of freshwater crabs
in the Museo de Zoología of the Universidad
de Costa Rica contains specimens that cover a
time span of dozens of years and thus provides
an important source of information that can be
used to detect possible changes in species distri-
butions through time and space, for example in
relation to climate change impacts and habitat
destruction. The value of these collections,
however, are generally underappreciated by the
public, policymakers, and funding agencies (see
Suarez & Tsutsui, 2004), and therefore, it will be
of special importance to explain and highlight
the significance of maintaining and expanding
these collections not only by publications in sci-
entific journals, but especially by involving the
public, for example by citizen science (Simo-
niello et al., 2019). Future strategies aimed to
complete our knowledge about freshwater crabs
should include people and communities living
in different parts of Costa Rica. The results of a
meaningful engagement of citizens will help to
guide for example future efforts to collect fresh-
water crabs and thus, allow a more efficient use
of the limited financial resources available for
these field trips and inventories.
Although our knowledge about freshwater
crabs in Costa Rica has increased considerably
especially during the last decades, informa-
tion about many aspects of the life history and
ecology of these invertebrates remains frag-
mentary or simply absent. For example, fresh-
water crabs are secondary intermediate hosts
9
Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
for metacercariae of the trematode Paragoni-
mus spp., and the consumption of undercooked
or raw freshwater crabs infected with these
metacercariae can lead to the contraction of
paragonimiasis or lung fluke disease (see Blair,
2022). One early study in Costa Rica focused on
this topic (Brenes et al., 1968). and more recent-
ly Hernández-Chea et al. (2017) confirmed the
presence of two species of Paragonimus, Pa.
caliensis and Pa. mexicanus, in freshwater crabs
collected in Costa Rica. However, and consider-
ing the wide distribution of freshwater crabs in
the country, their role as food item and, there-
fore, the importance of this topic for public
health, additional studies are required to obtain
a more complete picture of freshwater crabs
as hosts of Paragonimus spp. and to increase
awareness of this disease in the health system
and prevention in the Costa Rican population.
The field of behavior has been mostly
neglected in freshwater crab research and not
only in Costa Rica, except for the field stud-
ies of freshwater crab predation on frog clay
models (see above). No laboratory experiment
has been conducted to gather information on
freshwater crab behavior. For example, it would
be interesting to study parental care in these
macroinvertebrates, since females carry their
offspring for an extended period of time (see
Wehrtmann et al., 2010). An adequate labora-
tory setting could be an ideal place to observe
and describe the interaction female-offspring
while the juveniles are attached to their mother.
Prolonged brood care is one of the evolution-
ary cues for the successful colonization of
Fig. 3. Sampling locations in Costa Rica where freshwater crabs were encountered (based on Magalhães et al., 2015).
10 Revista de Biología Tropical, ISSN: 2215-2075 Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
freshwater habitats (Vogt, 2013; Vogt & Tolley,
2004), and the results of such laboratory obser-
vations (maybe accompanied by field studies)
might help to identify the ecological and evo-
lutionary pressures involved in the evolution
of (prolonged) maternal care (see also Palaoro
& Thiel, 2020).
Climate change impacts on freshwater
crabs have yet not been studied in Costa Rica.
A recent worldwide review (Toh et al., 2022)
found only 49 publications with empirical evi-
dence of climate change effects on freshwater
decapods, and the majority of these publica-
tions referred to crayfishes Astacidea. Climate
change scenarios for Costa Rican montane for-
ests, one of the principal habitats of freshwater
crabs, predict an increase of temperature and a
decrease in precipitation in these areas, which
may have serious implications for mountain
ecosystems (Karmalkar et al., 2008). Therefore,
and considering the severe impacts already
shown for some freshwater crab species (see
Toh et al., 2022), future studies about this topic
are encouraged to assess their vulnerability to
climate change impacts and to foster adequate
conservation interventions and measures for
this threatened group of decapods.
Climate change is not the only threat for
freshwater crabs. Their survival is also imper-
iled by pollution, deforestation, habitat loss,
and invasive species (Cumberlidge et al., 2014;
Toh et al., 2022). There is an urgent need to
obtain more information about these topics,
and Costa Rica with its relatively high species
diversity would be an ideal place to study how
these threats affect the ecology and survival
of freshwater crabs. For example, Martín-Tor-
rijos et al. (2021) detected the crayfish plague
pathogen Aphanomyces astaci in an introduced
population of the crayfish Procambarus clarkii
in Costa Rica, and modeling results (Azofeifa-
Solano et al., 2023) revealed that this crayfish
showed a relatively high probability to invade
mountain ranges, which can be also occupied
by freshwater crabs. The consequences of such
niche overlap as well as the possible infection
of freshwater crabs with the crayfish plague
pathogen Ap. astaci needs to be assessed.
Another example for an open research area
is the contamination of freshwater crabs with
microplastics (MPs), which is a hazardous pol-
lutant of global concern, impacting mainly but
not exclusively aquatic ecosystems and human
health as people may consume decapod crusta-
ceans, such as freshwater crabs, contaminated
with MPs (D’Costa, 2022; de Miranda & de
Carvalho-Souza, 2016). Although studies on
the presence of MP in freshwater decapods
are scarce (see D’Avignon et al., 2021), a recent
study (Yu et al., 2023) revealed the presence
of considerable amounts of MPs in freshwater
crabs from aquaculture ponds in the Yangtze
River Delta of China. An integrative study on
the contamination of Costa Rican river systems
should certainly include freshwater crabs, since
they spend their entire life in these aquatic sys-
tems and may serve as a possible indicator for
MP contamination.
When developing future research strategies
including freshwater crabs, it is recommend-
able considering synergistic effects of different
stressors, including for example climate change,
deforestation, pollution, and non-native spe-
cies (Toh et al., 2022). Such an approach will
require multidisciplinary research projects,
which might also generate species-specific
information on freshwater crabs. Such data are
essential for the development and implementa-
tion of management plans to protect the local
biodiversity.
Ethical statement: the authors declare that
they all agree with this publication and made
significant contributions; that there is no con-
flict of interest of any kind; and that we fol-
lowed all pertinent ethical and legal procedures
and requirements. All financial sources are fully
and clearly stated in the acknowledgments sec-
tion. A signed document has been filed in the
journal archives.
ACKNOWLEDGMENTS
ISW sincerely appreciates the ongoing sup-
port by the Vicerrectoría de Investigación of
the Universidad de Costa Rica (projects B2718,
11
Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
B3504, B5655, B6773, and C2721), which
allowed him to foster the research about fresh-
water crabs. We would like to thank Monika
Springer and Gerardo Umaña for facilitating
literature about aquatic environments in Costa
Rica. We also acknowledge the financial support
received from the Conselho Nacional de Desen-
volvimento Científico e Tecnológico (CNPq
- Brazil, Procs. 491490/2004-6, 490353/2007-
0, 490314/2011-2; 471011/2011-2), CONICIT
- Costa Rica (CII-001-08, IQ-0001-11), and
Biota FAPESP (Temáticos 2010/50188-8 and
INTERCRUSTA 2018/13685-5) that allowed
the development of a long-term international
cooperative project during the Brazil-Costa
Rica program. Last not least, we sincerely
appreciate the collaboration with Raquel Rome-
ro Chaves, who prepared Figure 2.
REFERENCES
Abdallah, A., De Mazancourt, C., Elinge, M. M., Graw, B.,
Grzesiuk, M., Henson, K., Kamoga, M., Kolodziejska,
I., Kristersson, M., Kuria, A., Leonhartsberger, P.,
Matemba, R., Merl, M., Moss, B., Minto, C., Murfitt,
E., Musila, S. N., Ndayishiniye, J., Nuhu, D., ... Yona,
M. (2004). Comparative studies on the structure of an
upland African stream ecosystem. Freshwater Forum,
21, 27–47.
Abell, R., Thieme, M. L., Revenga, C., Bryer, M., Kottelat,
M., Bogutskaya, N., Coad, B., Mandrak, N., Contreras
Balderas, S., Bussing, W., Stiassny, M. L. J., Skelton,
P., Allen, G. R., Unmack, P., Naseka, A., Ng, R., Sin-
dorf, N., Robertson, J., Armijo, E., ... Petry, P. (2008).
Freshwater ecoregions of the world: a new map of
biogeographic units for freshwater biodiversity con-
servation. BioScience, 58(5), 403–414.
Acevedo-Alonso, A., & Cumberlidge, N. (2021). Chapter
13: Updated extinction risk assessment of the Colom-
bian freshwater crabs (Brachyura: Pseudothelphusi-
dae, Trichodactylidae) reveals an increased number of
threatened species. In T. Kawai & D. C. Rogers (Eds.),
Recent advances in freshwater crustacean biodiversity
and conservation (Advances in Crustacean Research,
Book 22) (pp. 405–423). Taylor & Francis Group.
https://doi.org/10.1201/9781003139560
Álvarez, F., & Villalobos, J. L. (1998). Six new species of
fresh-water crabs (Brachyura: Pseudothelphusidae)
from Chiapas, Mexico. Journal of Crustacean Biology,
18(1), 187–198.
Álvarez, F., Ojeda, J. C., Souza-Carvalho, E. A., Villalobos,
J. L., Magalhães, C., Wehrtmann, I. S., & Mantelatto,
F. L. (2020). Revision of the higher taxonomy of
Neotropical freshwater crabs of the family Pseu-
dothelphusidae Ortmann, 1893, based on multi-
gene and morphological analyses. Zoological Journal
of Linnean Society, 193(3), 973–1001. https://doi.
org/10.1093/zoolinnean/zlaa162
Azofeifa-Solano, J. C., Villalobos-Rojas, F., Romero-Chaves,
R., & Wehrtmann, I. S. (2023). Modeling the habi-
tat suitability of two exotic freshwater crayfishes
in Mesoamerica and the Caribbean: Cherax quad-
ricarinatus (von Martens, 1868) and Procambarus
clarkii Girard, 1852 (Decapoda: Astacidea: Parastaci-
dae, Cambaridae). Journal of Crustacean Biology, 43,
ruad059. https://doi.org/10.1093/jcbiol/ruad059
Baringer, B. (2019). Predation rates between different color
morphs of freshwater crabs (Ptychophallus sp.) using
clay models in the Quebrada Máquina stream sys-
tem in Monteverde, Costa Rica [Technical report,
pp. 44–52). Council on International Educational
Exchange, Tropical Ecology & Conservation, Monte-
verde, Costa Rica.
Bayliss, J. (2002). The East Usumbara tree-hole crab
(Brachyura: Potamoidea: Potamonautidae) – a strik-
ing example of crustacean adaptation in closed can-
opy forest, Tanzania. African Journal of Ecology, 40,
26–34.
Blair, D. (2022). Lung flukes of the genus Paragonimus: ancient
and reemerging pathogens. Parasitology, 149, 1286–
1295. https://doi.org/10.1017S0031182022000300
Bott, R. (1967). Fluß-Krabben aus dem westlichen Mittel-
amerika (Crust. Decap.). Senckenbergiana Biologica,
48(5/6), 373–380.
Bott, R. (1968). Fluß-Krabben aus dem östlichen Mittel-
Amerika und von den Großen Antillen (Crustacea,
Decapoda). Senckenbergiana Biologica, 49(1), 39–49.
Brenes, R., Zeledón, R., & Rojas, G. (1968). The finding
of Paragonimus sp. in mammals, crabs and snails in
Costa Rica. Boletín Chileno de Parasitología, 23, 164.
Campos, M. R., & Lemaitre, R. (1999). Two new freshwater
crabs of the genus Ptychophallus Smalley, 1964 (Crus-
tacea: Decapoda: Brachyura: Pseudothelphusidae)
from Panama, with notes on the distribution of the
genus. Proceedings of the Biological Society of Wash-
ington, 112(3), 553–561.
Collen, B., Whitton, F., Dyer, E. E., Baillie, J. E. M., Cumber-
lidge, N., Darwall, W. R. T., Pollock, C., Richman, N.
I., Soulsby, A. M., & Böhm, M. (2014). Global patterns
of freshwater species diversity, threat and endemism.
Global Ecology and Biogeography, 23, 40–51. https://
doi.org/10.1111/geb.12096
Corajod, J. (2015). Sexual dimorphism and habitat prefer-
ences of Monteverde freshwater stream crabs [Techni-
cal report, pp. 137–145). Council on International
Educational Exchange, Tropical Ecology & Conserva-
tion, Monteverde, Costa Rica.
12 Revista de Biología Tropical, ISSN: 2215-2075 Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
Coto-Pacheco, R., Ruiz Valverde, W., Castro Ulate, L.,
Recinos González, M., & Porras Porras, A. (2005).
Inventario nacional de cuerpos de aguas continentales
de Costa Rica [Reporte técnico]. Plan Regional de
Pesca y Acuicultura Continental & Instituto Costar-
ricense de Pesca y Acuacultura, San José, Costa Rica.
Cumberlidge, N. (2016). Chapter 1. Global diversity
and conservation of freshwater crabs (Crustacea:
Decapoda: Brachyura). In T. Kawai & N. Cumber-
lidge (Eds.), A Global Overview of the Conserva-
tion of Freshwater Decapod Crustaceans (pp. 1–22).
Springer International Publishing AG. https://doi.
org/10.1007/978-3-319-42527-6_1
Cumberlidge, N., Alvarez, F., & Villalobos, J. L. (2014).
Results of the global conservation assessment of the
freshwater crabs (Brachyura, Pseudothelphusidae and
Trichodactylidae): the Neotropical region, with an
update on diversity. ZooKeys, 457, 133–157. https://
doi.org/10.3897/zookeys.457.6598
Cumberlidge, N., & Ng, P. K. L. (2009). Systematics, evolu-
tion, and biogeography of freshwater crabs. In J. W.
Martin, K. A. Crandall & D. L. Felder (Eds.), Decapod
Crustacean Phylogenetics (pp. 491–508). CRC Press.
Cumberlidge, N., & Vannini, M. (2004). Ecology and taxon-
omy of a tree-living freshwater crab (Brachyura: Pota-
moidea: Potamonautidae) from Kenya and Tanzania,
East Africa. Journal of Natural History, 38(6), 681–
693. https://doi.org/10.1080/0022293021000041716
D’Avignon, G., Gregory-Eaves, I., & Ricciardi, A. (2021).
Microplastics in lakes and rivers: an issue of emerging
significance to limnology. Environmental Reviews, 30,
228–244. https://doi.org/10.1139/er-2021-0048
D’Costa, A. H. (2022). Microplastics in decapod crusta-
ceans: accumulation, toxicity and impacts, a review.
Science of the Total Environment, 832, 154963. https://
doi.org/10.1016/j.scitotenv.2022.154963
de Miranda, D. A., & de Carvalho-Souza, G. F. (2016).
Are we eating plastic-ingesting fish? Marine Pollu-
tion Bulletin, 103, 109–114. https://doi.org/10.1016/j.
marpolbul.2015.12.035
Deleva, S., Ulloa, A., Oliveira, H. F., Simov, N., Didonna, F.,
& Chaverri, G. (2023). Cave-dwelling fauna of Costa
Rica: current state of knowledge and future research
perspectives. Subterranean Biology, 47, 29–62.
Dudgeon, D., Arthington, A. H., Gessner, M. O., Kawa-
bata, Z. I., Knowler, D. J., Lévêque, C., Naiman, R.
J., Prieur-Richard, A. H., Soto, D., Stiassny, M. L. J.,
& Sullivan, C. A. (2006). Freshwater biodiversity:
importance, threats, status and conservation chal-
lenges. Biological Reviews, 81(2), 163–182. https://doi.
org/10.1146/10.1017/S1464793105006950
Funk, V. A. (2018). Collections-based science in the 21st
century. Journal of Systematics and Evolution, 56(3),
175–193. https://doi.org/10.1111/jse.12315
Garlick-Ott, K. (2017). Freshwater crab dispersion and
habitat use in a cloud forest stream [Technical report,
pp. 64–75]. Council on International Educational
Exchange, Tropical Ecology & Conservation, Monte-
verde, Costa Rica.
Grinang, J., Min, P. Y., & Ng, P. K. (2015). A new species
of tree-hole dwelling freshwater crab of the genus
Arachnothelphusa Ng, 1991 (Crustacea: Decapoda:
Brachyura: Gecarcinucidae) from northern Sarawak,
Malaysia, Borneo. The Raffles Bulletin of Zoology, 63,
454–460.
Hernández-Chea, R., Jiménez-Rocha, A. E., Castro, R.,
Blair, D., & Dolz, G. (2017). Morphological and
molecular characterization of the metacercaria of Par-
agonimus caliensis, as a separate species from P. m e x i -
canus in Costa Rica. Parasitology International, 66(2),
126–133. https://doi.org/10.1016/j.parint.2016.12.006
Hobbs III, H. H. (1991). A new pseudothelphusid crab from
a cave in southern Costa Rica (Decapoda: Brachyura).
Proceedings of the Biological Society of Washington,
104(2), 295–298.
Hobbs III, H. H. (1993). Section 8 - Fauna of southern
Costa Rica caves. Journal of Caves and Karst Studies,
55(1–2), 8.1–8.13.
Karmalkar, A. V., Bradley, R. S., & Diaz, H. F. (2008).
Climate change scenario for Costa Rican montane
forests. Geophysical Research Letters, 35(11), L11702.
Kohlmann, B., Roderus, D., Elle, O., Solís, Á., Soto, X., &
Russo, R. (2010). Biodiversity conservation in Costa
Rica: a correspondence analysis between identified
biodiversity hotspots (Araceae, Arecaceae, Brome-
liaceae, and Scarabaeinae) and conservation priority
life zones. Revista Mexicana de Biodiversidad, 81(2),
511–559.
Lara, L. R., Wehrtmann, I. S., Magalhães, C., & Mantelatto,
F. L. (2013). Species diversity and distribution of
freshwater crabs (Decapoda: Pseudothelphusidae)
inhabiting the basin of the río Grande de Térraba,
Pacific slope of Costa Rica. Latin American Jour-
nal of Aquatic Research, 41(4), 685–695. https://doi.
org/10.3856/vol41-issue4-fulltext-5
Lobo, R. G., Azofeifa, P. L., & Hilje Quirós, L. (2021). La
biodiversidad de Costa Rica en dos siglos de vida
independiente, y una mirada hacia el tricentenario.
Revista del Archivo Nacional de Costa Rica, 85, e529.
Magalhães, C., Lara, L. R., & Wehrtmann, I. S. (2010). A new
species of freshwater crab of the genus Allacanthos
(Crustacea, Decapoda, Pseudothelphusidae) from
southern Costa Rica, Central America. Zootaxa, 2604,
52–60. https://doi.org/10.11646/zootaxa.2604.1.4
Magalhães, C., Wehrtmann, I. S., Lara, L. R., & Mantelatto, F.
L. (2015). Taxonomy of the freshwater crabs of Costa
Rica, with a revision of the genus Ptychophallus Smal-
ley, 1964 (Crustacea: Decapoda: Pseudothelphusidae).
13
Revista de Biología Tropical, ISSN: 2215-2075, Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
Zootaxa, 3905(3), 301–344. https://doi.org/10.11646/
ZOOTAXA.3905.3.1
Martín-Torrijos, L., Correa-Villalona, A. J., Azofeifa-Sola-
no, J. C., Villalobos-Rojas, F., Wehrtmann, I. S.,
& Diéguez-Uribeondo, J. (2021). First detection of
the crayfish plague pathogen Aphanomyces astaci in
Costa Rica: European mistakes should not be repeat-
ed. Frontiers in Ecology and Evolution, 9, 623814.
https://doi.org/10.3389/fevo.2021.623814
Masese, F. O., Kitaka, N., Kipkemboi, J., Gettel, G. M., Irvine,
K., & McClain, M. E. (2014). Macroinvertebrate func-
tional feeding groups in Kenyan highland streams:
Evidence for a diverse shredder guild. Freshwater Sci-
ence, 33(2), 435–450. https://doi.org/10.1086/675681
Mittermeier, R. A., Robles-Gil, P., Hoffman, M., Pilgrim,
J., Brokks, T., Mittermeier, C. G., Lamoreux, J., & da
Fonseca, G. A. B. (2014). Hot spots revisted, Earth’s
biologically richest and most endangered terrestrial
ecoregions. CEMEX.
Palaoro, A. V., & Thiel, M. (2020). “The caring crustacean”:
an overview of crustacean parental care. In R. D.
Cothran & M. Thiel (Eds.), Reproductive Biology. The
Natural History of the Crustacea (Vol. 6, pp.115–144).
Oxford University Press.
Poettinger, T. S., Klaus, S., & Schubart, C. D. (2016). Phy-
logenetic relationships among neotropical freshwater
crabs of the Pseudothelphusidae (Decapoda, Brachy-
ura) and the taxonomic position of Ptychophallus
and related genera. Crustaceana, 89(14), 1717–1728.
https://doi.org/10.1163/15685403-00003627
Pretzmann, G. (1965). Vorläufiger Bericht über die
Familie Pseudothelphusidae. Sitzungsberichte der
Mathematisch-Naturwissenschaftlichen Klasse der
Österreichischen Akademie der Wissenschaften, Wien,
1, 1–11.
Pretzmann, G. (1968). Neue südamerikanische
Süsswasserkrabben (Vorläufige Mitteilung). Entomol-
ogisches Nachrichtenblatt, 15, 1–15.
Pretzmann, G. (1972). Die Pseudothelphusidae (Crustacea
Brachyura). Zoologica, 42(120), 1–182.
Pretzmann, G. (1978). Neue Potamocarcinini, Poglay-
en-Neuwall leg. 1975 (vorläufige Mitteilung). Sit-
zungsberichte der Österreichischen Akademie der
Wissenschaften, Mathematisch Naturwissenchaftliche
Klasse, 1978(2), 51–54.
Pretzmann, G. (1980). Von Dr. Ivo Poglayen-Neuwall 1975
in Mittelamerika gesammelte Krabben. Annalen des
Naturhistorischen Museums, 83, 651–666.
Quirós, L. H. (2013). Los primeros exploradores de la ento-
mofauna costarricense. Brenesia, 80, 65–88.
Quirós, L. H. (2022). Las rutas históricas del desarrollo
de las ciencias biológicas en Costa Rica. Revista
Herencia, 35(1), 110–154. https://doi.org/10.15517/h.
v35i1.49908
Ramírez-Fernández, J. D., & Fernández-Vargas, M. (2020).
First record of Tweedy’s crab-eating Rat, Ichthyomys
tweedii Anthony, 1921 (Rodentia, Cricetidae, Sigmo-
dontinae), for Costa Rica. Check List, 16(2), 435–440.
https://doi.org/10.15560/16.2.435
Rathbun, M. J. (1893). Descriptions of new species of
American fresh-water crabs. Proceedings of the United
States National Museum, 16(959), 649–661. http://
dx.doi.org/10.5479/si.00963801.16-959.649
Rathbun, M. J. (1896). Descriptions of two new species of
fresh-water crabs from Costa Rica. Proceedings of the
United States National Museum, 18(1071), 377–379.
http://dx.doi.org/10.5479/si.00963801.18-1071.377
Rathbun, M. J. (1898). A contribution to a knowledge of
the fresh-water crabs of America. The Pseudothel-
phusinæ. Proceedings of the United States National
Museum, 21(1158), 507–537.
Rathbun, M. J. (1905). Les crabes d’eau douce (Pota-
monidae). Nouvelles Archives du Muséum d’Histoire
naturelle, 7(4), 159–321.
Revenga, C., & Kura, Y. (2003). Status and trends of biodi-
versity of inland water ecosystems [Technical report].
Secretariat of the Convention on Biological Diversity,
Montreal, Canada.
Rigler, M. (2012). Microhabitat, agonism, and territoriality
in three color morphs of a Neotropical cloud forest crab
[Technical report, pp. 89–101]. Council on Inter-
national Educational Exchange, Tropical Ecology &
Conservation, Monteverde, Costa Rica.
Rodriguez, G. (1982). Les crabes d’eau douce d’Amerique.
Famille des Pseudothelphusidae. Editions de
l’ORSTOM.
Rodríguez, G. (2001). New species and records of pseudo-
thelphusid crabs (Crustacea: Brachyura) from Central
America in the Museum of Natural History of Tulane
University. Proceedings of the Biological Society of
Washington, 114(2), 435–443.
Rodríguez, G., & Hedström, I. (2000). The freshwater crabs
of the Barbilla National Park, Costa Rica (Crustacea:
Brachyura: Pseudothelphusidae), with notes on the
evolution of structures for spermatophore retention.
Proceedings of the Biological Society of Washington,
113(2), 420–425.
Rodríguez, G., & Herrera, F. (1994). A new troglophilic
crab, Chaceus turikensis, from Venezuela, and addi-
tional notes on the stygobiont crab Chaceus caecus
Rodríguez and Bosque, 1990 (Decapoda: Brachy-
ura: Pseudothelphusidae). Mémoires de Biospéologie,
Moulis-Saint Girons, 21, 121–126.
14 Revista de Biología Tropical, ISSN: 2215-2075 Vol. 73(S1): e63633, enero-diciembre 2025 (Publicado Mar. 03, 2025)
Schmitt, W. L. (1969). Colombian freshwater crab notes.
Proceedings of the Biological Society of Washington,
82, 93–112.
Simoniello, C., Jencks, J., Lauro, F. M., Loftis, J. D.,
Weslawski, J. M., Deja, K., Forrest, D. R., Gossett,
S., Jeffries, T. C., Jensen, R. M., Kobara, S., Nolan, L.,
Ostrowski, M., Pounds, D., Roseman, G., Basco, O.,
Gosselin, S., Reed, A., Wills, P., & Wyatt, D. (2019).
Citizen-science for the future: Advisory case studies
from around the globe. Frontiers in Marine Science, 6,
225. https://doi.org/10.3389/fmars.2019.00225
Smalley, A. E. (1964). The river crabs of Costa Rica, and the
subfamilies of the Pseudothelphusidae. Tulane Studies
in Zoology, 12(1), 5–13.
Springer, M., Echeverría, S., & Gutiérrez, P. (2014). Costa
Rica. En P. Alonso-EguíaLis, J. M. Mora, B. Campbell
& M. Springer (Eds.), Diversidad, Conservación y Uso
de los Macroinvertebrados Dulceacuícolas de México,
Centroamérica, Colombia, Cuba y Puerto Rico (pp.
119–155). Instituto Mexicano de Tecnología del Agua,
Jiutepec, Morelos, México.
Suarez, A. V., & Tsutsui, N. D. (2004). The value of
museum collections for research and soci-
ety. BioScience, 54(1), 66–74. https://doi.
org/10.1641/0006-3568(2004)054[0066:TVOMCF]2.
0.CO;2
Toh, E. X., Gan, L. X., & Yeo, D. C. (2022). A global
overview of climate change impacts on freshwater
decapods: substantial research gaps across taxa and
biogeographic regions. Journal of Crustacean Biol-
ogy, 42(1), ruab088. https://doi.org/10.1093/jcbiol/
ruab088
Umaña, G., Haberyan, K. A., & Horn, S. P. (1999). Limnol-
ogy in Costa Rica. In R. G. Wetzel & B. Copal (Eds.),
Limnology in Developing Countries (pp. 33–62). Inter-
national Association for Theoretical and Applied
Limnology (SIL).
Villalobos, C. R. (1974). Ptychophallus costaricensis, a new
freshwater crab from Costa Rica. Revista de Biología
Tropical, 21(2), 197–203.
Villalobos, C. R., & Burgos, E. (1974). Potamocarcinus
(Potamocarcinus) nicaraguensis (Pseudothelphusidae:
Crustacea) en Costa Rica. Revista de Biología Tropical,
21(2), 223–237.
Vogt, G. (2013). Abbreviation of larval development and
extension of brood care as key features of the evo-
lution of freshwater Decapoda. Biological Reviews,
88(1), 81–116.
Vogt, G., & Tolley, L. (2004). Brood care in freshwater
crayfish and relationship with the offspring’s sensory
deficiencies. Journal of Morphology, 262(2), 566–582.
https://doi.org/10.1002/jmor.10169
Wehrtmann, I. S., Hernández-Díaz, D., & Cumberlidge, N.
(2019). Freshwater crabs as predators and prey: The
case of Ptychophallus uncinatus Campos & Lemai-
tre, 1999 (Brachyura, Pseudothelphusidae) from
Costa Rica, Central America. Latin American Jour-
nal of Aquatic Research, 47(1), 18–26. https://doi.
org/10.3856/vol47-issue1-fulltext-3
Wehrtmann, I. S., Magalhães, C., & Bello-González, O. C.
(2016a). First confirmed report of a primary fresh-
water crab (Brachyura: Pseudothelphusidae) asso-
ciated with bromeliads in the Neotropics. Journal
of Crustacean Biology, 36(3), 303–309. https://doi.
org/10.1163/1937240X-00002429
Wehrtmann, I. S., Magalhães, C., Hernáez, P., & Mantelatto,
F. L. (2010). Offspring production in three freshwater
crab species (Brachyura: Pseudothelphusidae) from
the Amazon region and Central America. Zoolo-
gia (Curitiba), 27, 965–972. https://doi.org/10.1590/
S1984-46702010000600019
Wehrtmann, I. S., Ramírez, A., & Pérez-Reyes, O. (2016b).
Chapter 9. Freshwater decapod diversity and conser-
vation in Central America and the Caribbean. In T.
Kawai & N. Cumberlidge (Eds.), A global overview
of the conservation of freshwater decapod crustaceans
(pp. 267–301). Springer International Publishing AG.
https://doi.org/10.1007/978-3-319-42527-6_9
Willink, B., García-Rodríguez, A., Bolaños, F., & Pröhl,
H. (2014). The interplay between multiple preda-
tors and prey colour divergence. Biological Journal
of the Linnean Society, 113(2), 580–589. https://doi.
org/10.1111/bij.12355
Yang, C., Wenger, S. J., Rugenski, A. T., Wehrtmann, I. S.,
Connelly, S., & Freeman, M. C. (2020a). Freshwater
crabs (Decapoda: Pseudothelphusidae) increase rates
of leaf breakdown in a neotropical headwater stream.
Freshwater Biology, 65(10), 1673–1684. https://doi.
org/10.1111/fwb.13524
Yang, C., Wehrtmann, I. S., Wenger, S. J., & Rugen-
ski, A. T. (2020b). Neotropical freshwater
crabs (Decapoda: Pseudothelphusidae) shred
leaves. Nauplius, 28, e2020020. https://doi.
org/10.1590/2358-2936e2020020
Yeo, D. C. J., Ng, P. K. L., Cumberlidge, N., Magalhães,
C., Daniels, S. R., & Campos, M. R. (2008). Global
diversity of crabs (Crustacea: Decapoda: Brachyura)
in freshwater. Hydrobiologia, 595(1), 275–286. https://
doi.org/10.1007/s10750-007-9023-3
Yu, F., Pei, Y., Zhang, X., Wu, X., Zhang, G., & Ma, J. (2023).
Occurrence and distribution characteristics of aged
microplastics in the surface water, sediment, and crabs
of the aquaculture pond in the Yangtze River Delta of
China. Science of the Total Environment, 871, 162039.
https://doi.org/10.1016/j.scitotenv.2023.162039
