NOTES ON GEOGRAPHIC DISTRIBUTION
Check List 13(4): 81–85
https://doi.org/10.15560/13.4.81
First records of Croaking Gourami, Trichopsis vittata (Cuvier, 1831)
(Teleostei: Osphronemidae), from Myanmar and Bangladesh
Michael Norén,1 Sven O. Kullander,1 Md. Mizanur Rahman2, Abdur Rob Mollah2
1 Department of Zoology, Swedish Museum of Natural History, P.O. Box 50007, SE-104 05, Sweden. 2 Department of Zoology, University of
Dhaka, Dhaka-1000, Bangladesh.
Corresponding author: Michael Norén, michael.noren@nrm.se
Abstract
The Croaking Gourami, Trichopsis vittata (Cuvier, 1831), is native to Southeast Asia and Sundaland, with introductions reported from USA, Philippines and India. The species was found by us in Myanmar (1997 and 2013), and
Bangladesh (2014 and 2016). DNA analysis supports the view that T. vittata is a species complex. Specimens from
Bangladesh, Myanmar and the European aquarium trade are the same genotype as specimens from Thailand, possibly
corresponding to Trichopsis harrisi Fowler, 1934, considered a synonym of T. vittata. Non-native populations are
likely due to release from aquarium specimens.
Key words
DNA barcode; COI; ornamental fish; invasive species; Bangladesh; Myanmar.
Academic editor: Zeehan Jaafar | Received 13 January 2017 | Accepted 16 May 2017 | Published 12 July 2017
Citation: Norén M, Kullander SO, Rahman MM, Mollah, AR (2017) First records of Croaking Gourami, Trichopsis vittata (Cuvier, 1831) (Teleostei:
Osphronemidae), from Myanmar and Bangladesh. Check List 13 (4): 81–85. https://doi.org/10.15560/13.4.81
Introduction
Trichopsis vittata (Cuvier, 1831), known as Croaking
Gourami in the ornamental fish trade, is a small airbreathing osphronemid fish, reported as native from
Java, Borneo, Sumatra, Peninsular Malaysia, Thailand,
and the Mekong basin in Cambodia, Laos, and Vietnam (Kottelat 1985, Rainboth 1996, Baird et al. 1999).
Trichopsis vittata is found in shallow, slow-flowing or
stagnant waters with abundant vegetation, such as rice
fields, roadside ditches, and irrigation canals. It is able
to survive in brackish water up to 20 psu salinity, and
in temperatures down to 7.2 °C (Schofield and Schulte
2016). It feeds on small planktonic crustaceans and insect
larvae (Rainboth 1996). The male is territorial and builds
a small inconspicuous bubble nest among the vegetation,
in which the eggs are deposited and guarded by the male
until the larvae become free-swimming (Britz et al. 2001,
Liengpornpan et al. 2006). Due to its small size there is
no targeted fishery for T. vittata, but it is occasionally
sold in markets as part of mixed catches, and is regularly
seen in the ornamental fish trade (Rainboth 1996).
The FAO Introduction of Species database lists T.
vittata as introduced only to the USA, where a feral
population has persisted in southern Florida since the
1970s (Lee et al. 1980, Schofield and Pecora 2013), but
established feral populations of T. vittata have also been
reported from the Philippines (BFAR 2006), without supporting data, and most recently from Chennai in Tamil
Nadu, India (Knight and Balasubramanian 2015). Here
Copyright Norén et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original author and source are credited.
5 Mar. 2016
19 Mar. 2016
19 Mar. 2016
23.5135 90.2049
24.0472 91.1026
23.884 91.2012
Old Brahmaputra Turag River at Ashulia point near Dhaka city
Meghna
Shorail, roadside ditch 8 km north of Brahmanbaria
Meghna
Titas River in Akhaura
1
3
65
12
2
3
3
5
NRM 69396, 69461
NRM 69220, 69434–69435
NRM 68345, 69493
NRM 68562
Bangladesh
Bangladesh
Bangladesh
25 Feb. 2016
23.3850 90.2046
Dhaleshwari River near Abdullahpur Bridge, Keranigonj
24 Nov. 2013
25 Nov. 2013
1 Dec. 2014
2 Dec. 2014
95.4884
95.3312
90.3844
90.2964
16.9992
17.1451
23.8985
23.544
Small stream in village, alongside road, 3 km NE Pantanaw, 75 km WNW Yangon
Small stream in Kha Yaykan village, 9 km N Innma village, 95 km NW Yangon
Turag River at Kamarpare, near Dhaka city
Fish market in Shonbari, Sreenagar
Date
16 Mar. 1997
1 Jan. 2002
17 Mar. 2008
17 Mar. 2008
17 Mar. 2008
24 Nov. 2013
24 Nov. 2013
Lon. °E
97.3356
—
97.3621
97.3887
97.6261
95.5895
95.9441
Lat. °N
17.0131
—
16.9271
16.9086
16.8331
17.1036
16.9113
Locality
Roadside ditch at Zayitchaung village, on the road Kyaikto-Thaton, 5 km before Thaton
Kawkareik market
Thathon market
God Chaung, 2 miles on the way from Thathon to Pha-An
Roadside ditch near bridge over Salween River at Tayoke Hla village, 5 miles to Pha-An
Lake in small village, north of Nyaungdon, 68 km NW Yangon
Irrigation channel on road Yangon - Pathein, 25 km NW Yangon
Genbank Acc# River drainage
Salween
Salween
Salween
Salween
KT250368
Salween
KY327369
Ayeyarwaddy
KY327368
Yangon
KY327370
Myanmar
KY327372
Ayeyarwaddy
Myanmar
KY327371
Ayeyarwaddy
Bangladesh KY349109
Old Brahmaputra
Bangladesh KT250365
Old Brahmaputra
KT250367
Bangladesh KY327373
Old Brahmaputra
KY327374
Country
Myanmar
Myanmar
Myanmar
Myanmar
Myanmar
Myanmar
Myanmar
All vouchered localities in Myanmar and Bangladesh are
presented in Table 1 and mapped in Figure 1. All listed
specimens were collected using beach seine or handheld
nets, or purchased at fish markets, and morphologically
identified. The standard barcoding region of the mitochondrial cytochrome c oxidase subunit I (COI) gene
was sequenced from 5 T. vittata collected in Bangladesh,
6 collected in Myanmar, and 3 aquarium specimens
(GenBank accession numbers: KT250366, KY327366,
KY327367) purchased in Sweden, using the primers and
protocol of Ward et al. (2005).
The obtained DNA sequences were assembled in
Geneious version 9 (Kearse et al. 2012), and combined
with all 134 COI sequences identified as T. vittata, T.
cf. vittata, or T. sp. cf. vittata deposited on GenBank, to
produce a matrix from which to estimate sequence divergence as pairwise p-distance, the percentage of differing
nucleotide sites between 2 compared DNA sequences
(please note that this is a simple measure of dissimilarity and different from the similarly-named statistical
term p-value). A neighbor-joining majority rule bootstrap
tree (Jukes-Cantor model, 500 repetitions, random addition sequence) rooted with Betta macrostoma (GenBank
Accession number KM485437) was produced to visualize genetic similarity (not shown) The Identification tool
of the Barcode of Life portal (http://boldsystems.org) was
used to obtain the Barcode of Life Barcode Index Numbers (BINs) of clusters of similar published sequences,
corresponding to putative species. Voucher specimens are
deposited in the collections of Dhaka University and the
Swedish Museum of Natural History.
Published occurrence data used to construct occurrence map (Fig. 2) were obtained from the Academy
of Natural Sciences at Philadelphia, Auburn University
Museum of Natural History, California Academy of
Sciences, Field Museum, Florida Fish and Wildlife Conservation Commission, Illinois Natural History Survey,
GBIF-MNHN (Paris), Oregon State University, Royal
Ontario Museum, Florida Museum of Natural History,
University of Michigan Museum of Zoology, United
States National Museum of Natural History, Smithsonian
Institution, Yale University Peabody Museum, and Natural History Museum of Denmark (Accessed through the
Fishnet2 Portal, http:www.fishnet2.net, 2015-5-26).
Collecting was made with permission from the Department of Environment in Bangladesh to the Department of
Zoology, University of Dhaka, and from the Department
of Fisheries in Myanmar to Swedish teams.
n
1
6
1
1
101
12
83
Methods
Voucher numbers
NRM 39950
USNM 378943
NRM 58106
NRM 58339
NRM 58410–58584, 67131
NRM 65183, 65291, 66324
NRM 65142, 65145, 65146, 66311–66312,
66395–66398
NRM 67073
NRM 67056-67058
NRM 66672-66674, 66676–66681, 67094–67095
NRM 66578–66581, 67096
we present additional localities from Myanmar and Bangladesh, up to 1000 km west of the natural range of the
species and 1500 km northeast of the previously known
feral population in Chennai, and discuss the origin and
future development of feral T. vittata in South Asia.
Check List 13(4): 81–85
Table 1. Voucher data for the non-native Croaking gourami (Trichopsis vittata) recorded from Myanmar and Bangladesh. NRM = Swedish Museum of Natural History; USNM = National Museum of Natural History,
Smithsonian Institution (database record only).
82
Norén et al. | First records of Trichopsis vittata from Myanmar and Bangladesh
83
Figure 1. Distribution of Trichopsis vittata in Asia, based on occurrence records in FishNet II (1906–2014), Knight and Balasubramanian
(2015), and University of Dhaka and Swedish Museum of Natural History records (Myanmar 1997–2013; Bangladesh 2014, 2016). BD =
Bangladesh.
Results
Trichopsis vittata can be separated from the 2 other currently recognized species in the genus, Trichopsis pumila
(Arnold, 1936) and Trichopsis schalleri Ladiges, 1962, by
the presence of a thin dark line below the eye. Trichopsis
vittata also grows to a larger maximum size, and normally
has 3 longitudinal dark bands on the posterior half of the
body instead of 2 as in T. schalleri and T. pumila (in T.
pumila the upper of the 2 bands is broken into a row of dark
spots surrounded by iridescent scales) (Fig. 2). Rainboth
(1996) states that T. vittata grows up to 70 mm standard
length (SL). Sithtananan (2010) measured 848 individuals
from all over the native distribution and found a maximum
length of 48.8 mm SL, and average length 31 mm SL.
The individual was a juvenile, showing that the species
was already reproducing in the region. In 2008, numerous specimens were collected at different localities in
Kayin State in eastern Myanmar, and in 2013 we found
numerous specimens at different localities in southern
Discussion
There are no published records of T. vittata from Bangladesh or Myanmar previous to the present report, not even
from the Myanmar portion of the Mekong River, but the
species has been common in collections from Indochina
and Indonesia for more than a century, suggesting that
the Tenasserim and Sino-Burman ranges separating the
Indochinese watersheds from the Burmese have been
a barrier to westward dispersal (Fig. 1). In 1997, staff
from the Swedish Museum of Natural History collected
a single T. vittata from a roadside ditch 5 km north of
the town of Thaton, in Mon State in eastern Myanmar.
Figure 2. Trichopsis vittata. A. Live male specimen photographed
in aquarium (not preserved), B. Preserved specimen (NRM67094c),
32.8 mm SL, collected from Turag River, Bangladesh, 2014. The dark
pigmented line below the eye is a diagnostic character for T. vittata.
84
Myanmar west of the city of Yangon, and additional
specimens were obtained in the Kawkareik district in
eastern Myanmar by Mr. U Tin Win. The earliest records
of T. vittata from Myanmar are from the eastern part of
the country, but no collections are available from the
same time in western Myanmar, so the dispersal within
Myanmar should not be assumed to have been from east
to west. In 2014 we found the species in abundance in the
Turag River, a tributary of the lower Brahmaputra flowing through Dhaka, and at the fish market in the nearby
Sreenagar (Dhaka Division) in central Bangladesh (Table
1). The species was recorded again in 2016 from the
Turag River, and also in the nearby Dhaleswari River as
well as 2 localities in the lower Meghna River northeast
of Dhaka (Table 1). No T. vittata were found in southeastern Bangladesh (Chittagong Division) during a survey in
2015, or in northeastern Bangladesh (Sylhet Division),
surveyed in 2016, despite the presence of suitable habitat.
Panijpan et al. (2015) analyzed mitochondrial COI
and nuclear RAG1 DNA sequences of a large number of
Trichopsis from Southeast Asia, and found that T. vittata
is not a single species but a species complex comprising
4 ecologically and morphologically similar but genetically distinct biological species. However, there were no
DNA sequences available from Java, the type locality
of T. vittata (Roberts 1996), and Panijpan et al. (2015)
were unable to determine which, if any, of these 4 clades
represented the true T. vittata. Dahruddin et al. (2016)
published 6 sequences of T. vittata from Java, which
in our analysis correspond to the clade that Panijpan et
al. (2015) referred to as “Trichopsis cf. vittata 4”, from
southern Thailand (BIN cluster ID BOLD:AAB9368).
As a coarse empirical rule-of-thumb, for the COI
gene, the dissimilarity between any 2 members of the
same species is typically < 1%, while the dissimilarity
between members of different species is typically ≥ 2%
(Ward 2009). This disjunct distribution of genetic similarity has been termed “the barcode gap” (Meyer and Paulay
2005), and can be used as an indicator of species affinity through a so-called barcode analysis, where a DNA
sequence from an unidentified specimen is compared to
a database of corresponding DNA sequences from wellidentified specimens, allowing confident identification
also of single unknown sequences.
The COI sequences of T. vittata from Myanmar,
Bangladesh, and the ornamental fish trade are similar
(≤ 0.6% p-distance) to each other and to 78 published
COI sequences, corresponding to a clade Panijpan et
al. (2015) referred to as “Trichopsis sp. (cf. vittata) 3”
(BIN cluster ID BOLD:ACS9775), from western and
central Thailand, but dissimilar (> 2.4% p-distance) to all
individuals of T. vittata from other areas. This supports
the conclusion by Panijpan et al. (2015) that the current
T. vittata is a species complex, and indicates that T. vittata sold in the ornamental fish trade in Europe and the
introduced populations in Bangladesh and Myanmar all
originates from central and western Thailand. According
to Panijpan et al. (2015), “Trichopsis sp. (cf. vittata) 3” is
Check List 13(4): 81–85
distributed in Thailand from Chiang Mai in the northwest,
to Trat in the southeast, and Surat Thani in the south.
Fowler (1934) described T. harrisi from Kratt (Trat), but
Kottelat (2001) considered T. harrisi a junior synonym of
T. vittata. A taxonomic revision of Trichopsis is needed,
and may come to the conclusion that the correct name for
“Trichopsis sp. (cf. vittata) 3” is T. harrisi.
The probable source of the feral population of T.
vittata in Florida is a nearby ornamental fish farm, and
also in the other locations the presumed source is release
of ornamental fish (Schofield and Pecora 2013, Knight
and Balasubramanian 2015). However, while Thailand is
a major exporter of ornamental fish, and T. vittata does
occur in the ornamental fish trade, it is not common.
Pygmy gourami (T. pumila) is the most common species of Trichopsis in the ornamental fish trade, but feral
populations have only been reported from the Philippines
(BFAR 2006), without data. This suggests either that T.
vittata is able to colonize new territory even when propagule size and frequency are low, or that it spreads also
through some mechanism other than release of aquarium
fish, such as intentional release for biological control of
mosquitos or as a contaminant among shipments of live
fish for aquaculture.
Wongsiri (1982) found that in Thailand the 3 most
important fish predators of mosquito larvae were T. vittata, Guppy (Poecilia reticulata Peters, 1859) and Tilapia
(Oreochromis sp.). The ability of T. vittata to survive in
very small volumes of water, and to tolerate polluted or
low-oxygen water, could make it suitable for mosquito
control, but we can find no record of it having been intentionally released as a mosquito control agent.
Another possible avenue for introduction is as a contaminant in shipments of live aquaculture fish. The small
East Asian Topmouth Gudgeon, Pseudorasbora parva
(Temminck & Schlegel, 1846), was introduced to Eastern Europe as a contaminant with fingerlings of Chinese
cyprinids imported for aquaculture trials and has since
spread to many river systems in Europe (Gavriloaie et al.
2008). In Asia, T. vittata could spread as a contaminant in
shipments of for instance live Silver Barb, Barbonymus
gonionotus (Bleeker, 1849), native to Southeast Asia,
sympatric with T. vittata, and an important aquaculture
species in South and Southeast Asia (Gupta and Rab
1994), but both Myanmar and Bangladesh have a range
of cultured species (Siddiqui et al. 2007) which present
similar potential. Nevertheless, the records from India,
Myanmar and Bangladesh are close to major cities, where
aquarium releases are more likely, and in the absence of
evidence that T. vittata spreads as a contaminant, and considering that the feral populations are genetically similar
to specimens from the aquarium trade, we consider the
release of specimens from the aquarium trade the most
probable mechanism of introduction.
Trichopsis vittata has many of the traits typical of
efficient invaders: it is able to tolerate polluted or low
oxygen conditions, is human-associated (through aquaria,
rice fields, and its ability to survive in degraded habitats),
Norén et al. | First records of Trichopsis vittata from Myanmar and Bangladesh
has a short generation time, guards its eggs (uniparental
care), and has a prior history of successful invasions. The
preferred habitat of T. vittata (shallow, often temporary,
vegetated waters with seasonal floods) corresponds to all
areas suitable for rice-production, suggesting that it could
potentially colonize most of southern and eastern Asia.
However, T. vittata does not have any mechanism for
long-distance dispersal, as it is non-migratory and does
not have planktonic eggs or larvae, and non-human mediated spread is likely to be slow. In addition, it may locally
be limited by life-history variables or interactions with
the native biota, as seems to be the case with the population in Florida (Schofield and Schulte 2016).
No negative effects resulting from introduction of T.
vittata have been reported, but Knight and Balasubramanian (2015) speculated that in India it may compete
for niche space with native small osphronemids such as
Dwarf Gourami [Trichogaster lalius (Hamilton, 1822)]
and Spiketail Paradisefish [Pseudosphromenus cupanus
(Cuvier, 1831)]. Other potential negative effects include
aggressive displacement of native species, or that it may
act as a vector for non-native parasites or pathogens, such
as the trematode Euclinostomum heterostomum (Rudolphi, 1809) (Purivirojkul and Sumontha 2013).
Acknowledgements
This study is part of the project “Genetic characterization
of freshwater fishes in Bangladesh using DNA barcodes”
(Swedish Research Council, contract D0674001 to Sven
Kullander and Abdur Rob Mollah).
Authors’ Contributions
All authors contributed to collection and text. MN and
MR extracted and sequenced DNA. MN made the analyses. SOK made images and table.
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