ArticlePDF Available

Occurrence of non-native red cherry shrimp in European temperate waterbodies: a case study from Hungary

  • Hungarian University of Agriculture and Life Sciences

Abstract and Figures

The international pet trade has caused numerous introductions of non-native species globally. This is true also for freshwater decapod crustaceans including the red cherry shrimp. This tiny creature has been previously found in thermally-polluted waters in Europe (Germany and Poland). Here we present its first occurrence in Hungary and in the entire Carpathian Basin. The species was sampled once per month over one year, from November 2017 to November 2018 in a natural thermal pond (spa) and also in an adjoining non-thermal brook in Miskolctapolca, Hungary. Shrimps were preyed upon by adult fishes in the locality but many individuals, including ovigerous females and juveniles, were recorded within the survey continuously. The density of shrimps was positively correlated with the water temperature, despite some individuals being found in the non-thermal stream and also in winter. We consider that the population of this species in Hungary is now well-established and self-sustaining.
Content may be subject to copyright.
Occurrence of non-native red cherry shrimp in European
temperate waterbodies: a case study from Hungary
András Weiperth
, Veronika Gábris
, Tibor Danyik
, Anna Farkas
, Pavlína Kuříková
Antonín Kouba
, and Jiří Patoka
MTA Centre for Ecological Research, Danube Research Institute, Karolina
ut 29, 1113 Budapest, Hungary
Eötvös Loránd University, Center of Environmental Science, Pázmány Péter sétány 1/C, 1117 Budapest, Hungary
Hortobágyi National Park Directorate, Sumen str. 2., 4024 Debrecen, Hungary
Herman Ottó Institute Nonprot Ltd, Park str. 2., 1223 Budapest, Hungary
Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Department of Zoology and Fisheries,
ycká 129, 16500 Prague-Suchdol, Czech Republic
University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of
Aquaculture and Biodiversity of Hydrocenoses, Záti
sí 728/II, 38925 Vodňany, Czech Republic
Abstract The international pet trade has caused numerous introductions of non-native species
globally. This is also true for freshwater decapod crustaceans including the red cherry shrimp. This tiny
creature has been previously found in thermally polluted waters in Europe (Germany and Poland).
Here, we present its rst occurrence in Hungary and in the entire Carpathian Basin. The species was
sampled once per month over 1 yr, from November 2017 to November 2018 in a natural thermal pond
(spa) and also in an adjoining non-thermal brook in Miskolctapolca, Hungary. Shrimps were preyed
upon by adult shes in the locality but many individuals, including ovigerous females and juveniles,
were recorded within the survey continuously. The density of shrimps was positively correlated with
the water temperature, despite some individuals being found in the non-thermal stream and also in
winter. We consider that the population of this species in Hungary is now well-established and self-
Keywords: Neocaridina / Europe / ornamental species / pet trade / Atyidae
Résumé Présence de crevettes rouge cerise non indigènes dans les eaux tempérées d'Europe : une
étude de cas en Hongrie. Le commerce international des animaux de compagnie a provoqué de nombreuses
introductions d'espèces non indigènes dans le monde. C'est également vrai pour les crustacés décapodes
d'eau douce, y compris la crevette rouge cerise. Cette minuscule créature a déjà été trouvée dans des eaux
thermiquement polluées en Europe (Allemagne et Pologne). Nous présentons ici sa première observation en
Hongrie et dans l'ensemble du bassin des Carpates. L'espèce a été échantillonnée une fois par mois sur une
période d'un an, de novembre 2017 à novembre 2018, dans un étang thermal naturel (spa) ainsi que dans un
ruisseau non thermique adjacent à Miskolctapolca, en Hongrie. Les crevettes étaient la proie des poissons
adultes dans la localité, mais de nombreux individus, y compris des femelles ovigères et des juvéniles, ont
été échantillonnés de façon continue pendant le suivi. La densité des crevettes était corrélée positivement
avec la température de l'eau, malgré la présence de certains individus dans le cours d'eau non thermique et
aussi en hiver. Nous considérons que la population de cette espèce en Hongrie est maintenant bien établie et
Mots-clés: Neocaridina / Europe / espèce ornementales commerce des animaux de compagnie / Atyidae
*Corresponding author:
Knowl. Manag. Aquat. Ecosyst. 2019, 420, 9
©A. Weiperth et al., Published by EDP Sciences 2019
Knowledge &
Management o
Ecosystems Journal fully supported by Onema
This is an Open Access article distributed under the terms of the Creative Commons Attribution License CC-BY-ND (, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited. If you remix, transform, or build upon the material, you may not distribute the modied material.
1 Introduction
The international pet trade in aquatic species is known to
be one of the main vectors of non-native species introduction
and spread into new localities (Padilla and Williams, 2004;
Duggan, 2010;Chucholl, 2013;Patoka et al., 2016b,2018b).
In contrast to ornamental sh, decapod crustaceans are
relatively new to the pet trade and have grown in popularity
in the aquarium industry in recent years (Papavlasopoulou
et al., 2014;Faulkes, 2015;Kotovska et al., 2016;Lipták et al.,
2017;Vodovsky et al., 2017). Tropical and subtropical
decapods usually have a low probability of establishing
populations within the temperate zone except in thermal
waterbodies, as documented in craysh Cambarellus patz-
cuarensis and Cherax quadricarinatus (Jakličand Vrezec,
2011;Weiperth et al., 2017), and shrimps Macrobrachium
dayanum and Neocaridina denticulata (Klotz et al., 2013;
Jabłońska et al., 2018). On the other hand, certain warm-water
species such as craysh Cherax destructor pose the potential to
overwinter in temperate climatic conditions (Vesel
yet al.,
The red cherry shrimp Neocaridina denticulata is a small
prolic and truthful freshwater species belonging to the family
Atyidae and is usually traded as the red cherry shrimp (Cai,
1996;Weber and Traunspurger, 2016). The taxonomical name
of this species is often confusing: some authors use different
synonyms such as N.heteropoda and N.davidi or suggest a
species complex (see Klotz et al., 2013 and citation herein).
Hence, this species will be further mentioned under its
common name in this study. The red cherry shrimp is one of the
most popular pet-traded freshwater crustacean species due to
its tiny size (adults 1530 mm long), attractive coloration, and
because it is an algae-eater (Turkmen and Karadal, 2012;
Uderbayev et al., 2017;Vazquez et al., 2017). It is native to
inland waterbodies in East Asia. It reproduces exclusively in
freshwaters without any pelagic larval stage (Tropea et al.,
2015). Therefore, the red cherry shrimp is common on the
market and frequently kept in hobby aquaria (Lipták and
Vitázková, 2015;Magalhães and Andrade, 2015;Patoka et al.,
There are many examples of decapods intentionally or
unintentionally introduced from aquaria to the wild (e.g.
Chucholl and Pfeiffer, 2010;Novitsky and Son, 2016;Patoka
et al., 2016c). Also, private outdoor garden ponds may serve as
a source for the subsequent spread of ornamental decapods to
adjoining localities (Peay, 2009;Patoka et al., 2014,2017). In
the case of the red cherry shrimp, the alternative pathway for
new introductions is also unintentional transport together with
live sh stock, as reported in China (Englund and Cai, 1999).
However, this species is mainly introduced via the pet trade in
new localities and has been reported in the wild in Germany,
Poland, and Japan (Nishino and Niwa, 2004;Klotz et al., 2013;
Jabłońska et al., 2018).
Once established, the red cherry shrimp is a highly
productive species (Schoolmann and Arndt, 2018) with
possible impacts on the ecosystem and associated biota. Oh
et al. (2003) noted that this shrimp is able to carry more than
batch of eggs within the season with optimal conditions. Weber
and Traunspurger (2016) found that foraging and predation by
these omnivorous shrimps resulted in an overall reduction in
abundance, biomass, and secondary production of meioben-
thos assemblages (benthic fauna larger than microfauna but
smaller than macrofauna, size 44 mm0.5 mm). Moreover, it
has been reported that the red cherry shrimp is a host of
numerous commensals which are transported in huge
quantities via the pet trade together with their host as
hitchhikers(Patoka et al., 2016a).
Both current international and local legislative regulations
focused on biological invasions in general and on the pet trade
in particular seem to be ineffective in many cases, and
paradoxically, often have the opposite effect than was
intended (Patoka et al., 2018a and citation herein). Thus,
new introductions of non-native ornamental species are likely
to be common, and data about their spread is crucial for
improving the management of affected freshwater ecosys-
tems. Schoolmann and Arndt (2018) predicted that the risk of
further spreading of the red cherry shrimp throughout
European waterbodies is possible. Therefore, to nd
potentially established population, we surveyed selected
thermal and non-thermal waterbodies in Hungary, a country
where the red cherry shrimp has been previously reported as a
commonly traded ornamental species and rated as medium
risk in terms of its potential invasiveness (Weiperth et al.,
2 Material and methods
2.1 Locality
The locality in Miskolctapolca (a suburb of Miskolc,
Hungary, Fig. 1) was selected according to the information
from the Facebook group of Hungarian shrimp fans: https:// The thermal
pond is used by humans in the area as a public spa and Hejő
brook is a regulated stream. We established ve sampling
points, two in thermal and three in non-thermal waterbody
(Tab. 1). Detailed characteristics of the locality and sampling
points are given in Table 2.
2.2 Data collecting
The locality was initially surveyed in November 2017.
Shrimps were sampled using ve baited (sh meat and halibut
pellets) plastic bottle traps at the rst sampling point, where
they were left overnight. Subsequently, all ve sampling
points were surveyed by trapping once per month for 1 yr.
Shrimps were also collected using handling nets and using a
backpack power generator electrosher (DEKA 3000 Lord)
along a 150-m transect downstream from each of three
sampling points in the brook and a 10-m transect at both
sampling points in thermal pond. All individuals from the
brook and all individuals from rst two samplings in thermal
water were preserved in pure ethanol (96%) for later
determination, while other individuals were released back to
the respective sampling points following identication.
Ichthyofauna in the locality (brook) was also surveyed by
electroshing in November 2017. Fish species were recorded
with some individuals euthanized for later dissection to
examine their stomach contents. The remaining sh were
released immediately following identication.
Page 2 of 7
A. Weiperth et al.: Knowl. Manag. Aquat. Ecosyst. 2019, 420, 9
2.3 Species determination
Preserved shrimps were morphologically examined fol-
lowing the characteristics in Englund and Cai (1999) and Klotz
et al. (2013). Three individuals were used for DNA analysis.
The initial morphological species identication was conrmed
by a molecular marker amplied by polymerase chain reaction.
A primer pair LCO1490 (50-GGTCAACAAATCATAAAGA-
CAAAAAATCA-30) was used for amplication of the COI
gene (Folmer et al., 1994). The DNA extraction and ampli-
cation was processed according to Patoka et al. (2016d).
The samples were sequenced using the Macrogen sequencing
service ( Chromatograms were assem-
bled and checked for potential errors. Edited sequences were
aligned using Clustal W, as implemented in the BioEdit
software package (Hall, 1999) and compared in NCBI
database in Basic Local Alignment Search Tools (BLAST)
(Madden, 2013). The obtained DNA sequences were deposited
in GenBank database.
3 Results
We found that the red cherry shrimp was well-established
in the locality, with many juveniles and ovigerous females
captured during the surveys. The obtained three mitochondrial
DNA sequences (COI gene) of length = 672 bp (GenBank acc.
nos. MH780819, MH780820 and MH780821) conrmed
the morphological identication of the captured shrimps as
N.denticulata (GenBank acc. no. JX156333.1, Yu et al., 2014).
The density of shrimps was positively correlated with the water
temperature. More than 1 km downstream from the mouth of
the thermal tributary to Hejőbrook, we sampled few shrimps
in the six-degree water in the autumn and winter (sampling
point 3). In the spring and summer, we found shrimps
more than 3 km downstream from the thermal spring (sampling
point 5). The majority of shrimps were captured among the
roots of Alnus sp. and Salix sp. Details about seasonal
variability in each sampling point including sex of captured
shrimps are given in Table 3 and Figure 2.
Fig. 1. Map showing the locality in Miskolctapolca, Hungary (indicated by red dot) (a), positions of ve sampling points (indicated by red
dots and numbers) (b), the sampling point 1 (thermal pond) (c), the sampling point 2 (outow from the thermal pond) (d), and sampling point 4
(Hejőbrook) (e).
Table 1. Name of the locality, number of the sampling point, type of
the waterbody (thermal or non-thermal), and GPS coordinates.
Locality No. of
Type GPS
1 Thermal 48°3044.500N, 20°44052.200 E
2 Thermal 48°3044.800N, 20°44054.200 E
Hejőbrook 3 Non-thermal 48°3048.100N, 20°44058.600 E
Hejőbrook 4 Non-thermal 48°405.500N, 20°45024.700 E
Hejőbrook 5 Non-thermal 48°4017.500N, 20°46033.000 E
Page 3 of 7
A. Weiperth et al.: Knowl. Manag. Aquat. Ecosyst. 2019, 420, 9
Table 3. Date of the sampling of red cherry shrimps (month and year) at ve sampling points, with number of captured individuals: females
(ovigerous females)/males/juveniles.
Date Sampling point
XI. 2017 79(42)/29/106 15(11)/36/88 10/3/8 1/7/9 0/4/1
XII. 2017 59(16)/36/99 25(8)/25/102 1/1/4 1/0/2 0/0/0
I. 2018 77(10)/48/152 28(11)/38/119 0/4/1 0/0/0 0/0/0
II. 2018 59(7)/26/108 19(9)/38/51 0/2/0 0/0/0 0/0/0
III. 2018 44(11)/63/88 1(5)/47/51 3/8/11 0/0/6 0/0/0
IV. 2018 59(21)/68/114 61(28)/91/123 11(2)/11/29 4(1)/5/11 0/2/0
V. 2018 41(26)/87/125 75(46)/91/105 29(17)/11/25 10(4)/10/26 2(1)/2/7
VI. 2018 71(39)/102/105 81(51)/103/136 39(8)/36/75 14(2)/25/36 7(1)/7/11
VII. 2018 72(35)/99/185 88(49)/115/204 38(15)/45/95 21(9)/16/15 5/2/19
VIII. 2018 56(21)/67/201 69(38)/125/165 55(5)/28/77 10(2)/19/41 1/9/15
IX. 2018 71(17)/88/102 96(81)/65/124 12(4)/16/23 2/7/22 3/4/18
X. 2018 68(51)/91/115 75(19)/41/115 8(4)/4/10 3/8/13 2/1/21
XI. 2018 83(61)/95/135 68(55)/62/95 1/2/0 5/1/2 1/3/5
Table 2. Detailed characteristics of the locality and sampling points with the range in each parameter over the complete survey.
Environmental parameters Sampling point
123 45
Water temperature (°C) 24.131.6 21.927.6 11.827.9 6.825.6 3.224.7
Water depth (m) >1.5 >1.5 0.10.7 0.30.6 0.20.9
Distance from the bank (m) 0.51.0 0.20.5 0.21.0 0.5 0.20.6
Water velocity (m/s) 0.3 0.31.0 1.22.3 0.91.8 0.71.6
Submerged vegetation (%) 515 <52060 1050 050
Emergent vegetation (%) 520 <5<5520 525
Woody debris (%) <5510 <510520
Shading tree cover (%) 020 530 1530 20 1030
Depth of sediment (m) 0.3 0.1 0.2 0.2 0.20.4
Type of sediment Rock, mud Rock, mud Clay, mud Clay, mud Mud
Fig. 2. Plots of captured red cherry shrimps (total numbers of females, ovigerous females, males, and juveniles) in thermal (red line) and
non-thermal water within the complete survey (divided to months: from XI. 2017 to XI. 2018).
Page 4 of 7
A. Weiperth et al.: Knowl. Manag. Aquat. Ecosyst. 2019, 420, 9
In the locality of the Hejőbrooks, we also found the
following macroinvertebrates: Asellus aquaticus,Gammarus
fossarum, larvae of Calopteryx splendens and C.virgo; and
sh species: Alburnus alburnus,Cyprinus carpio,Gobio
gobio,Lepomis gibbosus,Perca uviatilis,Rhodeus sericeus,
Rutilus rutilus,Scardinius erythrophthalmus,Squalius
cephalus, and Pseudorasbora parva. Juveniles of several sh
species were observed but not captured. Five adult G.gobio,
7L.gibbosus,10P.parva,17R.rutilus, and 21 S.cephalus
were euthanized for the dissection of their stomach and shrimp
remains were found in all dissected specimens.
4 Discussion
In this study, we report the occurrence of the red cherry
shrimp for the rst time in Hungary and from the entire
Carpathian Basin. Contrary to previous records from the
European territory (Klotz et al., 2013;Jabłońska et al., 2018),
we found this non-native decapod occurring not only in
thermal or thermally polluted waters, but also in adjacent
brook with seasonal uctuations in water temperature. The
origin of the collected shrimps is unknown because this species
is both directly imported from South-Eastern Asia, re-exported
from other European countries such as the Czech Republic,
and also produced locally in Hungary as an ornamental species
(Weiperth et al., 2018). Inasmuch as the release of unwanted
animals from aquaria or unintentional escape is a frequent
pathway for new introductions of non-native ornamental
species, including decapod crustaceans, we assume that they
were released by some local or spa-visiting hobby keeper(s).
Even if there are no available data about previous occurrences
of the red cherry shrimp in the locality, there is the possibility
that this species may have been established in the locality for
many years, as was case of this species' occurrence in Poland
(Jabłońska et al., 2018).
The red cherry shrimp inhabits small streams with rocky
bottoms and dense aquatic vegetation (Via u et al., 2016). The
locality was therefore found suitable with the limiting
environmental factor of water temperature. For the reason that
the temperature in the thermal pond reaches 24.131.6 °C,
which is an optimal temperature for reproduction of the red
cherry shrimp (Nur and Christianus, 2013;Tropea et al.,
2015), we assume that this reservoir is a primary source of
shrimps in the locality. Alternatively, the continual occur-
rence of individuals in the Hejőbrook suggests that the
adaptability of at least some of the red cherry shrimp
population towards lower temperatures and annual tempera-
ture uctuation is higher than previously expected; Mykles
and Hui (2015) noted that the red cherry shrimp grows and
reproduces at room temperature. Even if Tropea et al. (2015)
experimentally found the highest proportion of ovigerous red
shrimp females in water with a temperature of 28 °Cand
Mykles and Hui (2015) suggested 2225 °C as optimum, we
found some individuals in 11.8°C water. Even if the water
temperature inuences the duration of the incubation period
and the developmental time of embryos (Tropea et al., 2015),
we suggest that some individuals are also able to reproduce in
non-thermal natural waters in the temperate zone, and
successive generations could become adapted to these
conditions. Mizue and Iwamoto (1961) brieyreportedon
a successful overwintering of this shrimp in Japanese
freshwaters; however, neither water temperature nor other
environmental conditions were specied in the publication;
Oh et al. (2003) found this shrimp successfully reproducing
and overwintering in one Korean temperate stream, and our
data support this nding. Moreover, Serezli et al. (2017)
suggested that lower water temperature (below 23 °C) causes
a female-biased sex ratio in the population, which is crucial
for population viability.
The trade and keeping of ornamental decapod crustaceans
in freshwater aquaria are well-established in Hungary, and the
unique hydrological features of this country with its numerous
thermal springs and waterbodies serve as a perfect environ-
ment for exotic freshwater species to establish and ourish
(Weiperth et al., 2017,2018). On the other hand, we found the
red cherry shrimp also occurs in non-thermal streams. Hence,
even if the red cherry shrimp is generally perceived as an
invasive species (Serezli et al., 2017), our ndings potentially
raise the predicted invasiveness of this species, which was
assessed as a medium-risk in previously analyzed markets
trading in ornamental decapods (Uderbayev et al., 2017;
Weiperth et al., 2018). Although we have no data about any
symbionts attached on the carapace surface of captured
shrimps, the potential introduction of bdelloid rotifers, stalked
protozoans, and scutariellid temnocephalidans previously
found on shrimps imported from Indonesia (Patoka et al.,
2016a) cannot be excluded, and the probability of these
symbionts establishing new populations via shrimp introduc-
tions is unknown.
Despite the documented predatorprey interaction between
sh and the red cherry shrimp, the monitored population is
considered well-established and self-sustaining. However, the
red cherry shrimp has a great commercial potential as an
ornamental species, it has a status of non-indigenous and thus
undesirable species in the wild in Europe. Although the density
of captured shrimps (non-surprisingly) positively correlated
with the water temperature, some individuals were found in the
non-thermal stream and also in winter. Since this shrimp has
been mostly overlooked by policymakers and wildlife
managers as an invasive species, the data we present in this
study should change our approach to this species in the
freshwaters of Central Europe. However, a potential ban on
the trade of the red cherry shrimp, and related legislative
restrictions, will be probably ineffective in halting its spread
because it is a popular aquarium species. In line with the
recommendations of Patoka et al. (2018a), we regard that
the key to mitigating the risk of further spread and
establishment of the red cherry shrimp is by educating the
general public on the negative consequences of releasing
aquarium species into freshwaters.
Acknowledgments. This study was supported by the
Internal Grant Agency of the Czech University of Life
Sciences Prague CIGA(No. 20182013) and by the Ministry
of Education, Youth and Sports of the Czech Republic
projects CENAKVA(No. CZ.1.05/2.1.00/01.0024) and
CENAKVA II(No. LO1205 under the NPU I program).
The English was proofread by Andrew Hamer, University of
Page 5 of 7
A. Weiperth et al.: Knowl. Manag. Aquat. Ecosyst. 2019, 420, 9
Cai Y. 1996. A revision of the genus Neocaridina (Crustacea:
Decapoda: Atyidae). Acta Zootaxonom Sin 21: 129160.
Chucholl C. 2013. Invaders for sale: trade and determinants of
introduction of ornamental freshwater craysh. Biol Invasions 15:
Chucholl C, Pfeiffer M. 2010. First evidence for an established
Marmorkrebs (Decapoda, Astacida, Cambaridae) population in
Southwestern Germany, in syntopic occurrence with Orconectes
limosus (Ranesque, 1817). Aquat Invasions 5: 405412.
Duggan IC. 2010. The freshwater aquarium trade as a vector for
incidental invertebrate fauna. Biol Invasions 12: 37573770.
Englund RA, Cai Y. 1999. The occurrence and description of
Neocaridina denticulata sinensis (Kemp, 1918) (Crustacea:
Decapoda: Atyidae), a new introduction to the Hawaiian Islands.
Bishop Museum Occasional Papers 58: 5865.
Faulkes Z. 2015. The global trade in craysh as pets. Crust Res 44:
Folmer O, Black M, Hoeh W, Lutz R, Vrijenhoek R. 1994. DNA
primers for amplication of mitochondrial Cytochrome C oxidase
subunit I from diverse metazoan invertebrates. Mol Mar Biol
Biotechnol 3: 294299.
Hall TA. 1999. BioEdit: a user-friendly biological sequence
alignment editor and analysis program for Windows 95/98/NT.
Nucl Acid Symp Ser 41: 9598.
Jabłońska A, Mamos T, Gruszka P, Szlauer-Łukaszewska A, Grabowski
M. 2018. First record and DNA barcodes of the aquarium shrimp,
Neocaridina davidi, in Central Europe from thermally polluted
River Oder canal, Poland. Knowl Manag Aquat Ecosyst 419: 14.
JakličM, Vrezec A. 2011. The rst tropical alien craysh species in
European waters: the redclaw Cherax quadricarinatus (Von
Martens, 1868)(Decapoda, Parastacidae).Crustaceana 84: 651665.
Klotz W, Miesen FW, Hüllen S, Herder F. 2013. Two Asian fresh water
shrimp species found in a thermally polluted stream system in North
Rhine-Westphalia, Germany. Aquat Invasions 8: 333339.
Kotovska G, Khrystenko D, Patoka J, Kouba A. 2016. East European
craysh stocks at risk: arrival of non-indigenous craysh species.
Knowl Manag Aquat Ecosyst 417: 37.
Lipták B, Mojži
sová M, Gruľa D, Christophoryová J, Jablonski D,
Bláha M, Petrusek A, Kouba A. 2017. Slovak section of the Danube
has its well-established breeding ground of marbled craysh
Procambarus fallax f. virginalis.Knowl Manag Aquat Ecosyst
418: 40.
Lipták B, Vitázková B. 2015. Beautiful, but also potentially invasive.
Ekológia (Bratislava) 34: 155162.
Madden T. 2013. The BLAST sequence analysis tool. MD: National
Center for Biotechnology Information.
Magalhães ALB, Andrade RF. 2015. Has the import ban on non-
native red swamp craysh (Crustacea: Cambaridae) been effective
in Brazil? Neotrop Biol Conserv 10: 4852.
Mizue K, Iwamoto Y. 1961. On the development and growth of
Neocaridina denticulata de Haan. Bull Fac Fish Nagasaki Univ 10:
Mykles DL, Hui JH. 2015. Neocaridina denticulata: a decapod
crustacean model for functional genomics. Integr Comp Biol 55:
Nishino M, Niwa N. 2004. Invasion of an alien freshwater shrimp
Neocaridina denticulata sinensis to Lake Biwa. Omia (Lake Biwa
Research Institute News) 80: 3.
Novitsky RA, Son MO. 2016. The rst records of Marmorkrebs
[Procambarus fallax (Hagen, 1870) f. virginalis] (Crustacea,
Decapoda, Cambaridae) in Ukraine. Ecol Montenegrina 5: 4446.
Nur F, Christianus A. 2013. Breeding and life cycle of Neocaridina
denticulatasinensis (Kemp, 1918). Asian J AnimVet Adv 8: 108115.
Oh CW, Ma CW, Hartnoll RG, Suh HL. 2003. Reproduction
and population dynamics of the temperate freshwater shrimp,
Neocaridina denticulata denticulata (De Haan, 1844), in a Korean
stream. Crustaceana 76: 9931015.
Padilla DK, Williams SL. 2004. Beyond ballast water: aquarium and
ornamental trades as sources of invasive species in aquatic
ecosystems. Front Ecol Environ 2: 131138.
Papavlasopoulou I, Perdikaris C, Vardakas L, Paschos I. 2014. Enemy
at the gates: introduction potential of non-indigenous freshwater
craysh in Greece via the aquarium trade. Cent Eur J Biol 9: 18.
Patoka J, Bláha M, Devetter M, Rylková K, Čadková Z, Kalous L.
2016a. Aquarium hitchhikers: attached commensals imported
with freshwater shrimps via the pet trade. Biol Invasions 18:
Patoka J, Bláha M, Kalous L, Kouba A. 2017. Irresponsible vendors:
non-native, invasive and threatened animals offered for stocking
garden ponds. Aquat Conserv 27: 692697.
Patoka J, Bláha M, Kalous L, Vrabec V, BuřičM, Kouba A. 2016b.
Potential pest transfer mediated by international ornamental plant
trade. Sci Rep 6: 25896.
Patoka J, BuřičM, KolářV, Bláha M, Petrt
yl M, Franta P, Tropek R,
Kalous L, Petrusek A, Kouba A. 2016c. Predictions of marbled
craysh establishment in conurbations fullled: Evidences from
the Czech Republic. Biologia 71: 13801385.
Patoka J, Magalhães ALB, Kouba A, Faulkes Z, Jerikho R, Vitule
JRS. 2018a. Invasive aquatic pets: failed policies increase risks of
harmful invasions. Biodivers Conserv 27: 30373046.
Patoka J, Petrt
yl M, Kalous L. 2014. Garden ponds as potential
introduction pathway of ornamental craysh. Knowl Manag Aquat
Ecosyst 414: 13.
Patoka J, Wardiatno Y, Ali M, Yonvitner, Daisy W, Jerikho R, Takdir
M, Purnamasari L, Petrt
yl M, Kalous L, Kouba A, Bláha M.
2018b. Redclaw craysh, Cherax quadricarinatus (von Martens,
1868), widespread throughout Indonesia. BioInvasions Rec 7:
Patoka J, Wardiatno Y, Yonvitner, Kuříková P, Petrt
yl M, Kalous L.
2016d. Cherax quadricarinatus (von Martens) has invaded
Indonesian territory west of the Wallace Line: evidences from
Java. Knowl Manag Aquat Ecosyst 417: 39.
Peay S. 2009. Invasive non-indigenous craysh species in Europe:
recommendations on managing them. Knowl Manag Aquat Ecosyst
394395: 03.
Serezli R, Atalar MS, Hamzacebi S, Kurtoglu IZ, Yandi I. 2017. To
what extent does temperature affect sex ratio in red cherry shrimp,
Neocaridina davidi? The scenario global warming to offspring
sex ratio. Fresen Environ Bull 26: 75757579.
Schoolmann G, Arndt H. 2018. Population dynamics of the invasive
freshwater shrimp Neocaridina davidi in the thermally polluted
Gillbach stream (North Rhine-Westphalia, Germany). Limnologica
71: 17.
Tropea C, Stumpf L, Greco LSL. 2015. Effect of temperature on
biochemical composition, growth and reproduction of the
ornamental red cherry shrimp Neocaridina heteropoda heteropoda
(Decapoda, Caridea). PLoS One 10, e0119468.
Turkmen G, Karadal O. 2012. The survey of the imported freshwater
decapod species via the ornamental aquarium trade in Turkey.
J Anim Vet Adv 11: 28242827.
Uderbayev T, Patoka J, Beisembayev R, Petrt
yl M, Bláha M, Kouba
A. 2017. Risk assessment of pet-traded decapod crustaceans in the
Republic of Kazakhstan, the leading country in Central Asia.
Knowl Manag Aquat Ecosyst 418: 30.
Page 6 of 7
A. Weiperth et al.: Knowl. Manag. Aquat. Ecosyst. 2019, 420, 9
Vazquez ND, Delevati-Colpo K, Sganga DE, López-Greco LS. 2017.
Density and gender segregation effects in the culture of the
caridean ornamental red cherry shrimp Neocaridina davidi
Bouvier, 1904 (Caridea: Atyidae). J Crustacean Biol 37: 367373.
yL,BuřičM, Kouba A. 2015. Hardy exotics species in
temperate zone: can warm watercraysh invaders establish
regardless of low temperatures? Sci Rep 5: 16340.
Viau VE, Marciano A, Iriel A, López Greco LS. 2016. Assessment of
a biolm-based culture system within zero water exchange on
water quality and on survival and growth of the freshwater shrimp
Neocaridina heteropoda heteropoda. Aquac Res 47: 25282542.
Vodovsky N, Patoka J, Kouba A. 2017. Ecosystem of Caspian Sea
threatened by pet-traded non-indigenous craysh. Biol Invasions 7:
Weber S, Traunspurger W. 2016. Inuence of the ornamental red
cherry shrimp Neocaridina davidi (Bouvier, 1904) on freshwater
meiofaunal assemblages. Limnologica 59: 155161.
Weiperth A, Gál B, Kuříková P, Bláha M, Kouba A, Patoka J. 2017.
Cambarellus patzcuarensis in Hungary: The rst dwarf craysh
established outside of North America. Biologia 72: 15291532.
Weiperth A, Gál B, Kuříková P, Langrová I, Kouba A, Patoka J. 2018.
Risk assessment of pet-traded decapod crustaceans in Hungary
with evidence of Cherax quadricarinatus (von Martens, 1868) in
the wild. North-West J Zool e171303.
Yu YQ, Yang WJ, Yang JS. 2014. The complete mitogenome of the
Chinese swamp shrimp Neocaridina denticulata sinensis Kemp
1918 (Crustacea: Decapoda: Atyidae). Mitochondrial DNA 25:
Cite this article as: Weiperth A, Gábris V, Danyik T, Farkas A, Kuříková P, Kouba A, Patoka J. 2019. Occurrence of non-native red cherry
shrimp in European temperate waterbodies: a case study from Hungary. Knowl. Manag. Aquat. Ecosyst., 420, 9.
Page 7 of 7
A. Weiperth et al.: Knowl. Manag. Aquat. Ecosyst. 2019, 420, 9
... The introduction of non-indigenous species into sites beyond their native ranges and their subsequent adaptation cause significant biodiversity and socioeconomic losses worldwide (Ehrenfeld, 2010;Kouba et al., 2021b;Simberloff et al., 2013). The freshwater pet trade has a long history (Novák et al., 2020) as one of the main sources of the introductions-both intentionally and accidentally-of non-native species and escapes of traded organisms (Maceda-Veiga et al., 2016;Padilla & Williams, 2004;Patoka et al., 2017c;Weiperth et al., 2019a) and associated biota (Duggan, 2010;Ložek et al., 2021;Patoka & Patoková, 2021;Patoka et al., 2016a). Moreover, the legal regulation of the aquaculture sector is highly complex in the case of many of these identified invasive species (Patoka et al., 2018a). ...
... Thus, the most suitable habitats for them are thermal waters, as in the case of the crayfish Cherax quadricarinatus in Slovenia (Jaklič & Vrezec, 2011), shrimps Macrobrachium dayanum and Neocaridina denticulata in Germany (Klotz et al., 2013) and crayfish Cambarellus patzcuarensis and shrimp N. denticulata and Caridina cf. babaulti in Hungary (Maciaszek et al., 2021;Weiperth et al., 2017Weiperth et al., , 2019a. Freshwater ornamental shrimps do not pose such an invasion risk and are not released as frequently as crayfish. ...
... Hungary is a country with a thriving pet trade and advertisements for several freshwater decapod crustaceans are often seen (Weiperth et al., 2019b(Weiperth et al., , 2020. Thus, we decided to survey the Hejő thermal brook in Miskolctapolca (a suburb of Miskolc, Hungary), where non-native shrimps were recorded for the first time in the Carpathian Basin in 2017 (Weiperth et al., 2019a), to update occurrence data and identify potentially newly released species. ...
Full-text available
Ornamental aquaculture and the related pet industry are known to be important sources of non-native species worldwide. In the temperate zone, thermal waterbodies are attractive places for irresponsible owners to release unwanted freshwater pets including decapod crustaceans. Several non-native ornamental species have been reported in the thermal locality of Miskolctapolca (a suburb of Miskolc, Hungary). So we surveyed this site in March 2019–November 2021 to update local occurrence records and detect potentially newly released species. A well-established population of Neocaridina denticulata and the occurrence of Caridina cf. babaulti had previously been noted. However, for the first time at this site, we found the shrimps Atyopsis moluccensis, Caridina gracilirostris and C. multidentata, as well as the crayfish Procambarus virginalis, P. clarkii, Cherax quadricarinatus, C. boesemani and C. snowden, and several formally undescribed Cherax species originating from New Guinea. Furthermore, in most species, gravid females carrying eggs were also noticed. Three shrimps, A. moluccensis, C. gracilirostris and C. multidentata, were recorded for the first time in European wild. Further monitoring of this locality and better education of the general public regarding the risks associated with the release of non-native species are strongly recommended.
... Freshwater habitats, especially those experiencing degradation, are prone to biological invasions (Casatti et al. 2006). Thermal pollution of temperate streams or rivers, for example, may facilitate the establishment of exotic species (Klotz et al. 2013, Weiperth et al. 2019. The introduction of non-native species can have negative impacts on the recipient community by directly or indirectly affecting ecosystem functioning and biodiversity, even without establishment, e.g. ...
... Biological invasions are often linked to commercial success in the global pet trade (Gippet & Ber-telsmeier 2021), and decapods are no exception. Warm-adapted decapods have a low probability of becoming established in temperate waters, except for in thermally polluted waterbodies (Weiperth et al. 2019). Established populations of the atyid shrimp Neocaridina davidi, a popular aquarium pet originating from eastern and central China, have been reported in the USA, Japan, Israel, and Europe (Klotz et al. 2013, Jabłońska et al. 2018, Levitt-Barmats et al. 2019, Weiperth et al. 2019. ...
... Warm-adapted decapods have a low probability of becoming established in temperate waters, except for in thermally polluted waterbodies (Weiperth et al. 2019). Established populations of the atyid shrimp Neocaridina davidi, a popular aquarium pet originating from eastern and central China, have been reported in the USA, Japan, Israel, and Europe (Klotz et al. 2013, Jabłońska et al. 2018, Levitt-Barmats et al. 2019, Weiperth et al. 2019. Until now, N. davidi has primarily been investigated for epibionts such as Holtodrilus truncatus, Scutariella sp., Vorticella sp., and Cladogonium sp. ...
Full-text available
The release of ornamental pets outside their native range can directly or indirectly impact the recipient community, e.g. via the co-introduction of associated pathogens. However, studies on parasites associated with non-native species, in particular freshwater decapods, have focused mainly on a limited set of pathogens. Here we provide data for the first time on microsporidian parasites of the non-native ornamental shrimp Neocaridina davidi, collected in a stream in Germany. Furthermore, we confirm an ongoing range expansion of the warm-adapted N. davidi from thermally polluted colder water. In the investigated shrimps, the microsporidian parasite Enterocytozoon hepatopenaei and an unknown microsporidian isolate were detected, raising concerns about their transmission potential and pathogenicity on native crustacean species.
... Signal crayfish Pacifastacus leniusculus (Dana, 1852) is the second and most recent invasive crayfish species detected in the country (Horvatović et al. 2022). Although no other invasive crayfish species have been identified yet in the wild in Serbia, new pathways for their introductions have emerged, mainly in the shape of the irresponsible release of pet-traded individuals, as occurs in neighbouring Hungary (Weiperth et al. 2019a(Weiperth et al. , b, 2020 and elsewhere (Chucholl 2013;Patoka et al. 2014;Faulkes 2015a). For this reason, we decided to undertake a survey in Serbia in an attempt to detect the potentially invasive crayfish in the aquarium pet trade, that could pose a threat to freshwater ecosystems and their biodiversity in the country. ...
... The establishment of other traded crayfish species in Serbia cannot be ruled out, especially in thermal waters (Chucholl 2013;Kouba et al. 2014;Weiperth et al. 2019aWeiperth et al. , 2020, that are present in the country (Ivanović et al. 2019). For instance, the redclaw crayfish has been reported repeatedly from thermal localities in Hungary (Weiperth et al. 2019b(Weiperth et al. , 2020 and has become established in Slovenia (Jaklič and Vrezec 2011). ...
Full-text available
The aquarium pet trade is a source of potentially invasive crayfish species, which can be subsequently intentionally or unintentionally introduced into new environments. This can lead to biological invasions that represent a threat to native biodiversity and, in particular, freshwater ecosystem functioning. In global terms, Europe is the most affected region, and invasive crayfish species are increasing in number, establishing their populations and expanding their ranges. Despite being similarly affected, the situation in Serbia (SE Europe) has remained overlooked in this regard. A survey of the aquarium pet trade in this country revealed six different crayfish species traded as ornamentals. Marbled crayfish Procambarus virginalis Lyko, 2017, a well-known invader, was traded in more than half of the studied towns and cities in Serbia and is commonly available both in pet shops and through e-commerce (online selling). Other potentially invasive crayfish include the red swamp crayfish Procambarus clarkii (Girard, 1852) and the Florida crayfish Procambarus alleni (Faxon, 1884), both of which are already established in some European inland waters. The presence of invasive species in the aquarium pet trade in Serbia could theoretically lead to their occurrence in the wild. Given that, in terms of cost and feasibility, the best defence against biological invasions is prevention. A rapid response to the findings discussed here could be the key to prevent future invasions of Serbian freshwater ecosystems by non-native crayfish species.
... Also, there is growing trade of decapods as ornamental aquatic pets in Eastern Europe, with their intentional and unintentional release in the wild (Raghavan et al. 2013). In thermal waters, those decapods can establish persistent populations and possibly spread further, especially as the temperatures rise (Klotz et al. 2013;Jabłońska et al. 2018;Weiperth et al. 2019;Bláha et al. 2022). ...
... BioInvasions Records 11 (in press) wild (Raghavan et al. 2013). In thermal waters, those decapods can establish persistent populations and possibly spread further, especially as the temperatures rise (Klotz et al. 2013;Jabłońska et al. 2018;Weiperth et al. 2019;Bláha et al. 2022). ...
... The pet trade is a key driver of non-native aquatic species introductions (Patoka et al. 2020). There are numerous reports of the presence of ornamental aquatic animals in natural environments outside their native range (Weiperth et al. 2019;Mabrouki et al. 2020;Tarkan et al. 2021;Maciaszek et al. 2021a), most likely due to an intentionally release and/or as an escape from captivity (Hulme et al. 2008). Additionally, numerous non-native species, including molluscs, are not deliberately transported but arrive as commodity contamination (Patoka et al. 2016b(Patoka et al. , 2017Patoka & Patoková 2021). ...
Full-text available
In the European Union, aquarium pets are organisms intended for closed places (e.g., pet shops, garden ponds, home aquariums). Until April 2021, regulations did not require veterinary inspection of these animals within the EU, although there is a potential risk of such organisms being released into the environment along with their symbiotes or parasites. Currently, a “disease-free” declaration is required, but no aquarium snail pathogen that needs attention in international trade has been included in the list of potential hazards. Here, we intended to check whether molluscs from the pet trade could be a source of parasites. We answered this question by using Anentome helena, a popular commodity in the ornamental pet industry, as a research model. Snail specimens were randomly collected from aquarium pet stocks imported from Bangkok (Thailand) to Warsaw (Poland) in March 2020. In total, three specimens were subjected to histological examination and 27 specimens were autopsied. Histological analysis revealed that one snail was infected with rediae (and the cercariae inside them). Our study is the first to show the presence of digenean larvae in A. helena originating from the ornamental pet industry. The spread of such “hitchhikers” in non-native areas will likely be associated with threats to environmental and public health. Therefore, it is necessary to constantly draw public attention to the possible consequences of releasing ornamental pets into the non-native environment.
... In recent years, more Czech scientists focused on ornamental aquaculture and evaluated both related positive and negative aspects of this sector with overlaps to conservation, ecology, ethology, taxonomy, ecotoxicology, biological invasions, phylogenetics and other concerned scientific disciplines (e.g. Bláha et al., 2016;Kopecký et al., 2013;Kouba et al., 2016;Mrugała et al., 2019;Patoka et al., 2019aPatoka et al., , 2019bWeiperth et al., 2019;Kawai and Patoka, 2020;Yonvitner et al., 2020;Haubrock et al., 2021). ...
Ornamental aquaculture is an economically important industry with many enthusiasts worldwide. Much of the supply for the industry is provided by individuals and businesses in tropical countries because many ornamental species originated in the tropics. But Czechia, a temperate region in Central Europe, is an exception. Czech suppliers have significantly influenced the global freshwater ornamental aquaculture market for decades. Here we present and discuss the history of ornamental aquaculture in Czechia considering its geopolitical background, social status and history, pet-trade trends, overlapping to research activities, public education, and related risks and threads. We list the most traded and exported species, and list species that rarely reproduce in captivity, but that are successfully bred for commercial purposes by Czech producers globally, we introduce the term “Czech aquarium phenomenon” to describe the substantial economic and scientific importance of Czechia in ornamental aquaculture. Given that the diversity and volume of species traded are vast, we suggest the importance of this phenomenon for consideration to key stakeholders who design aquaculture policies, including the management of invasive alien species and ex-situ conservation programs for endangered species.
... Recently, Maciaszek et al. (2021) reported the invasion of S. japonica into Poland, Europe, which is likely due to intentional or unintentional releases of infected ornamental shrimp Neocaridina davidi (Bouvier, 1904). Used as fishing bait and ornamental shrimp, N. davidi have spread across the world (Englund and Cai 1999;Niwa 2010;Klotz et al. 2013;Jabłońska et al. 2018;Weiperth et al. 2019). ...
Full-text available
We report the first occurrence record of the freshwater ectoparasitic platyhelminth Scutariella japonica (Matjašič, 1990) from Hokkaido, Japan. The flatworms were collected from the surface of exoskeleton and the inside of branchial chamber of the atyid shrimp Neocaridina sp. aff. davidi. Phylogenetic analysis based on the 18S + 28S concatenated dataset of rhabdocoel flatworms retrieved the Scutariella clade, and our specimens identified with Scutariella japonica were genetically distinct from those referred to S. sinensis Chen, Feng, Lin, Lu & Wang, 2018. Phylogenetic analyses using COI showed that the host shrimp specimens from Sapporo were clustered with N. koreana identified by Shih et al. (2017) and placed close to N. palmata (Shen, 1948) and N. davidi (Bouvier, 1904). Our specimens did not agree with the original description of N. koreana Kubo, 1938, particularly in the shape of the endopod of the male pleopod 1. The identity of the present host shrimp specimens could not be established satisfactorily, and thus they were referred to N. sp. aff. davidi for the time being.
... La especie es omnívoro-detritívora, gregaria, con una longevidad estimada de 1,5 a 2 años y nativa de arroyos y lagos de países asiáticos, como Vietnam, China, Corea, Taiwan y Japón (Cai 1996). Sin embargo, a la fecha y como consecuencia del mercado de la acuariofilia, se la encuentra en varios países de Europa y América tanto en acuarios para su comercialización como en espacios naturales donde ha sido reconocido su potencial invasor (Jabłońska et al. 2018, Schoolmann et al. 2018, Weiperth et al. 2019, Levitt-Barmats et al. 2019. ...
... Their assessed risks of biological invasion are low and hence these crayfish are not banned there (Patoka et al. 2014). Surprisingly, despite the higher price of ornamental New Guinean crayfish (Chucholl 2013;Patoka et al. 2015c), several individuals were recently recorded released in Hungarian thermal waters (Weiperth et al. 2020) where also tropical shrimps were previously found (Weiperth et al. 2019). The possibility of a future ban proposal based on further monitoring cannot be excluded. ...
Full-text available
The pet trade is known to be one of the main sources of invasive species including freshwater crayfish, which cause socioeconomic losses and negative impacts on native biota in many regions where introduced. Indonesia was identified as the leading supplier of ornamental crayfish globally but the local market has been neglected even though certain non-native species were reported previously. Based on the survey of pathways and culture of ornamental crayfish in Java, six non-native species were recorded: Cherax destructor, C. quadricarinatus, C. peknyi, C. snowden, C. warsamsonicus, and P. clarkii. The latter species originates from North America and serves as a vector of crayfish plague, i.e. a disease lethal for non-North American crayfish species. Crayfish are cultured both in outdoor and indoor facilities as well as in natural lakes and reservoirs. Harvested crayfish are transported via numerous routes across most of the island of Java. It is obvious that the local market for ornamental crayfish is well-developed and Jakarta, Surabaya and Yogyakarta were identified as hotspots of this trade. Further monitoring, detailed analysis of the market and a ban of high-risk P. clarkii are recommended to improve management and existing legislation.
Full-text available
Businesses in the pet trade collect and transport many aquatic species around the globe, and some of these individuals are released into new habitats. Some jurisdictions have introduced laws intended to regulate this trade, but these regulations have rarely had the desired effects. Laws regarding pets and the pet trade are often poorly communicated, poorly enforced, and not aligned with hobbyists’ beliefs. Consequently, some laws may increase the number of unwanted introductions instead of decreasing them. A significant change in approach is needed, involving far greater communication with scientists, administrations, politicians, the pet industry, and pet owners, promoting euthanasia of unwanted pets rather than release, and the creation and promotion “white lists” of low risk species that can be sold in the pet trade.
Full-text available
The redclaw crayfish, Cherax quadricarinatus, is a freshwater crayfish native to northeastern Australia and southern New Guinea. In 2016, the species was found for the first time west of the Wallace Line in Java, Indonesia and, based on climate matching, its further spread within Indonesian territory was predicted. In this study, surveys of selected localities within Indonesia were performed to examine the species occurrence. Redclaw crayfish were found throughout Indonesia, in numerous rivers, lakes, ponds and reservoirs in Batam and Bintan Islands (Riau Archipelago), Java, Kalimantan (Borneo), Sulawesi and Sumatra. Some stocks were apparently well established, providing a food source for local people and sustaining capture for pet trade purposes. Because there are no effective regulations of introductions and exploitation of this crayfish in Indonesia, its further spread to new localities is expected. Increased attention to this issue, especially regarding crayfish management and policy implementation, is urgently needed.
Full-text available
Neocaridina davidi (Bouvier, 1904) is an exotic freshwater shrimp originating from Asia and often kept as a pet in amateur aquarium cultures. Herewith, we report on the second finding of N. davidi in fresh waters of Europe and the first discovery of that species both in Poland and in Central Europe. The species was found in samples collected in 2003, 2013 and 2017 in the thermally polluted canal connected to the River Oder, south of Gryfino, in the vicinity of the Dolna Odra Power Plant. The taxonomic identity of the collected shrimp was confirmed by the standard DNA barcoding procedure, using a 610 bp-long fragment of cytochrome oxidase I (COI). The findings spanning more than a decade suggest that N. davidi may have established a self-reproducing population at this site. Following the finding of Atyaephyra desmarestii (Millet, 1831) in 2000, Neocaridina davidi is the second freshwater shrimp species found in the River Oder and in Poland.
Full-text available
In 2017, a new non-indigenous crayfish species was found established in Europe. The captured individuals were identified as an orange morph of the Mexican dwarf crayfish Cambarellus patzcuarensis Villalobos, 1943. Fifteen adults (including three ovigerous females) and 26 juveniles were collected in a thermal pond in Budapest, Hungary. Two additional adults were caught below the pond’s outflow in the adjacent Danube River. To our knowledge, this is the first record of a C. patzcuarensis population outside North America, which is also true for the rest of dwarf crayfish (family Cambaridae, subfamily Cambarellinae). With this finding, indigenous crayfish species in Europe are now more than two-fold outnumbered by non-indigenous species. An analysis of the probability of establishment of C. patzcuarensis in continental Europe revealed that specific regions in the south of the continent are suitable areas for the establishment of the species. Moreover, as a confirmed carrier of the crayfish plague pathogen, this species should be treated with caution and eradicated if possible.
Full-text available
The pet trade is one of the most important sources of introduction of freshwater non-native decapod crustaceans. Precise and timely identification of potentially hazardous species is necessary for the effective prevention of new introductions. Here, we present a list of species of ornamental freshwater decapod crustaceans pet-traded in Hungary and their risk assessment, including the probability of establishment based on climate matching. The list contains 13 shrimps, eight crayfish, two crabs, and one hermit crab. Three crayfish, Cherax destructor, Procambarus clarkii, P. fallax f. virginalis, and one crab, Eriocheir sinensis, were classified in the high-risk category. During field sampling, we found three individuals of C. quadricarinatus that were probably released or escaped from aquaria. These are the first records of this species in the wild of Carpathian Basin. We strongly recommend further educating hobbyists about the risks related to the escapes and releases of high-risk taxa, as well as monitoring of the region for their occurrence.
Full-text available
An invasive freshwater shrimp, Red Cherry Shrimp (Decapoda: Caridea: Atyidae), is naturally distributed in fresh water habitats of Asia. This forage species has an important role in aquatic ecosystems by transferring planktonic production into higher trophic levels mainly including fish and aquatic animals. However, temperature strongly affects sex ratio and in turn offspring quantity. In order to determine the effect of temperature on incubation period, egg yield, offspring sex ratio as well as survival, a comprehensive experiment was conducted at three temperatures (20, 23 and 26ºC). Significant differences among temperatures for hatching period were an expected result. Higher survival and more eggs were achieved at 26ºC comparing the lower experimental temperatures. The female/male ratio, which was 80% at 20°C and approximately 50% at 23ºC, drastically dropped to 18% at 26°C. This ratio may drop to 0% at higher temperatures, which are tolerance limits for Red Cherry Shrimp. Therefore, in sex-dependent selective breeding, the temperature should be taken into consideration. Consequently , as temperature increases the sex ratio of the offspring increases in favour of the male. The continuation of global warming and rising above 26°C may be an important source of stress on the natural sustainability of Red Cherry Shrimp stocks.
Full-text available
Established populations of the non-indigenous parthenogenetically reproducing marbled crayfish Procambarus fallax f. virginalis have been recently reported from various European countries. The colonised sites are usually lentic and relatively isolated from major watercourses and in such cases the immediate threat of the spread of this taxon is limited. Here we report on a marbled crayfish population that is likely to become a seed for colonisation of the Danube in Slovakia. It is located in a channel within the Slovak capital Bratislava in the immediate vicinity of a pumping station that occasionally releases significant amounts of water into the side arm of the Danube. The population is well established with a high growth potential: numerous adult marbled crayfish individuals were observed at the site in September and October 2016 and the progeny (eggs or first two developmental stages) of 27 berried females exceeded 11 000 individuals. The maximum observed fecundity per female reached 647 juveniles in the second developmental stage. The Danube side arm downstream of the pumping station harbours a population of spiny-cheek crayfish Orconectes limosus infected with the crayfish plague pathogen Aphanomyces astaci. We presume that marbled crayfish is already present below the pumping station and it is just a matter of effort and time until it is discovered. The investigated specimens of marbled crayfish were found free of A. astaci, but horizontal transmission from infected spiny-cheek crayfish may be expected, as well as further spread of marbled crayfish in the Danube.
Full-text available
The pet trade with decapod crustaceans has been considered one of the main pathway of introduction of these animals worldwide. As the leading markets in this regards are the Czech Republic, Germany and the USA. Central Asia is not perceived as an important market with ornamental decapod crustaceans. Despite this assumption, we found at least 16 species of freshwater shrimp, crayfish and crab species pet-traded in the Republic of Kazakhstan, the largest country in this region. Considering computed risk assessment, the origin of particular species, their availability on the market, the probability of establishment and further aspects, we identified two crayfish Procambarus clarkii and Procambarus fallax f. virginalis being the seriously hazardous taxa with high potential to threaten native crayfish species as well as inhabited ecosystems. To prevent their introductions and to minimize the risks of mentioned species, similarly as in the case of European Union, we recommend the total ban of import, trade and keeping of these high-risk taxa within Central Asia.
Ornamental species of the aquarium pet trade contribute more and more to the introduction of previously exotic species in Europe. Among these, freshwater crustaceans play an increasingly larger role. Especially in thermally altered streams they may become invasive; however, field data on population ecology of invasive crustaceans are very rare. The aim of this study was to analyze the population dynamics of the invasive freshwater shrimp Neocaridina davidi (indigenous to China and other Asian countries) in a year-round warm-water habitat in the Gillbach stream (North Rhine-Westphalia, Germany), where this species forms a stable population. The species reached abundances between 0.23-1.39 individuals per m². N. davidi is highly productive and detectable in the whole Gillbach stream and in the lower Erft River, too. Egg ratio and cohort development were documented for a period of 27 months. Among adults, between 45 and 59 % were females (average 50.5 %). Life span was about 12 months in the field and up to 21 months under laboratory conditions. Development times under field and laboratory conditions were similar, ovigerous females appeared about 7 months after hatching. The population in the Gillbach stream was multivoltine with about two generations per year. Only 2-3 % of eggs reached adulthood in the field most probably due to intensive predation by indigenous and invasive fish species. One specimen could already be detected in the Lower River Rhine. N. davidi is omnivorous and well adapted to different freshwater habitats. The risk of further spreading to other European river systems is obvious.
A new species of the genus Caridina, C. longipoda sp. nov. from Hunan Province, China is described. Type specimens are deposited in the Institute of Zoology, Chinese Academy of Sciences, China.