Aquatic Hemiptera of Gauhati University,
Guwahati, Assam, India
Rabindra Hazarika 1 & Mrigendra M. Goswami 2
1,2Department of
Zoology, Gauhati University, Guwahati, Assam 781014, India
Email
: 1 hazarika.rabindra@gmail.com , 2mrigen_goswami@rediffmail.com
Date of publication (online): 26 March 2010
Date of publication (print): 26 March 2010
ISSN 0974-7907 (online) | 0974-7893 (print)
Editor: Subodh Sharma
Manuscript details:
Ms # o2315
Received 16 September 2009
Final received 08 December 2009
Finally accepted 08 February 2010
Citation: Hazarika, R. & M.M. Goswami (2010). Aquatic
Hemiptera of Gauhati University, Guwahati, Assam, India. Journal of Threatened Taxa 2(3): 778-782.
Copyright: © Rabindra Hazarika & Mrigendra M. Goswami 2010. Creative Commons Attribution 3.0 Unported License. JoTT
allows unrestricted use of this article in any medium for non-profit purposes,
reproduction and distribution by providing adequate credit to the authors and
the source of publication.
Acknowledgements: The authors are thankful to the
University Grants Commission, New Delhi, Government of India for providing
financial support in the form of Research Fellowship in Science for Meritorious
Students; Zoological Survey of India, Kolkata for identification of some
species and the Programme Coordinator of the UGC-SAP (DRS), Department of
Zoology, Gauhati University for providing necessary laboratory facilities.
For Figures, Images &
Tables – click here
Aquatic Hemiptera holds an important place in the ecology of
freshwater ecosystem. They are
important food for many organisms, including fish, amphibians, waterfowl and
other animals (Clark 1992). They
generally have an intermediate place in the food chain, for apart from being
eaten, are often important predators too (Runck & Blinn 1994). Hemipterans are exceedingly important
in relation to fish production. They are the primary food for many wild and cultivable
fishes, which make them valuable for sport fisheries. On the other hand, these
predators are also occasional pests in man-made nursery pond for fish culture
where they feed on the young fish. Certain families of the bugs may be utilized in the biological control
of mosquito larvae (Ohba & Nakasuji 2006; Saha et al. 2007).
A constituent of the Eastern Himalayan biodiversity hotspot, the
state of Assam harbors a rich diversity of aquatic resources. In recent years, there have been a
number of limnological investigations on the freshwater ecosystem of Assam but
little work has been done on the description of aquatic Hemipteran
population. Kalita (2008) recorded
nine Hemipteran species from Deepar Beel, one of the Ramsar sites in Assam,
while Chetri et al. (1997) reported seven species from the same wetland. Although Thirumalai (2002, 2007)
mentioned the occurrence of 56 species under the Infraorder Nepomorpha (43
species, 17 genera, six families) and Gerromorpha (13 species, 11 genera, three
families) from Assam, published literature on aquatic bugs is very scattered,
particularly in pond ecosystem. This study is carried out to bridge the gap in contributing towards the
knowledge of heteropteran population.
Study Area
The present work is based on the studies carried out for a period
of one year, commencing from July, 2007 to June, 2008 in two pond ecosystems
named as Pond A and Pond B (26009’26’’N & 91040’21’’E)
of the Aquaculture and Biodiversity Campus of Zoology Department, Gauhati
University, Guwahati, Assam, India (Figure 1, Image 1). Pond A is a manually managed pond,
triangular in shape with a mean depth of 2.2m having an area of 1.4 hac. Pond B is a naturally maintained
reclaimed swamp. The reclaimed zone is separated from the perennial swamp by a
bamboo made screen (locally “bana”). Pond B is rectangular in size with a mean depth of 1m
and having an area of 0.4 hac. In
comparison with Pond A macrophytic growth is more in
pond B. The ponds are rain fed and
perennial. The bottom surface of
Pond A comprises of loamy clay without any vegetation while in Pond B it
consists of silt sediments intermingled with decaying vegetation.
Material and Methods
Circular nets made of finely meshed polyester mosquito curtain
cloths were used to collect the floating/swimming insects from the littoral
zone of the studied habitat. Collection of insects associated with macrophytes was done with a hand
operated D-shaped dip-net with mesh size of approximately 500µm. Organisms were sorted and stored in 70%
ethyl alcohol. Insects were
identified to the lowest possible taxa using either a dissecting microscope or
a compound microscope. Identification of a number of species was confirmed in
the Central Entomological Laboratory of Zoological Survey of India,
Kolkata. Aquatic taxonomic keys
such as Pennak (1978), Bal & Basu (1994a, 1994b),
and Thirumalai (2002, 2007) were used to identify the collected specimens. Identification was mainly based on the
adults collected. Preservation was done by following both dry and wet methods ofpreservation and the paratypes were deposited in the Taxonomy and Biodiversity
Study Laboratory of UGC-SAP (DRS) Project, Department of Zoology, Gauhati
University.
Results and Discussion
Altogether 14 species comprising 12 genera and seven families have
been recorded in the present investigation; all belong to the suborder
Heteroptera. Family Nepidae
represents the highest number of species (four species) followed by Gerridae
(three species) and Belostomatidae (two species). Families such as Corixidae,
Notonectidae, Pleidae, Hydrometridae and Mesovelidae comprised one specie each. (Table 1). Pond B represents all the recorded
species while only 10 species were recorded in Pond A. Habitat complexity in
terms of presence or absence of littoral vegetation and hydromedian depth are
found to be the most important factors affecting the distribution of aquatic
hemiptera in the studied water bodies. Pond B representing intermediate
conditions between swamp and open water is aherbaceous natural water body dominated by water hyacinth serves as a unique
habitat for the colonization of rich and diverse species. In contrast, Pond A exhibits a
different condition in terms of depth (mean depth 2.2m) and vegetation cover,
without any dominant species of macrophytes during the study period.
The presently described species exceed the findings of Kalita
(2008) and Chetri et al. (1997). Kalita (2008) recorded nine Hemipteran species including one species (Rhopalosiphum nymphaeae Linnaeus) belonging to Suborder
Homoptera in Deepar Beel Ramsar site in Assam. The diversity of Hemipteran insects is also significantly
high in comparison to some studies in freshwater wetland inhabiting insects of
India. Deepa & Rao (2007)
recorded eight heteropteran Hemiptera from Pocharam Lake, Andhra Pradesh;
while, Bhattacharya (1998) described eight species in association with Eichhornia crassipes in some freshwater wetlands of
West Bengal and Khan (2002) also recorded eight species from two man-made lakes
of Kolkata. The number of recorded species in the present study signifies the
rich diversity of the group in the freshwater ecosystems of Assam. There is little information on the
abundance and distribution of aquatic bugs in freshwater bodies in Assam;
therefore it is necessary to make continuous censuses so that they can be
accessible for scientists who are interested in developing management plans to
protect aquatic resources.
References
Bal, A. & R.C. Basu
(1994a).
Insecta: Hemiptera: Mesovelidae, Hydrometridae, Veliidae and Gerridae, pp.
511-534. In: State fauna Series 3 : Fauna of West Bengal, Part
5, Zoological
Survey of India, Culcutta.
Bal, A. & R.C. Basu
(1994b). Insecta : Hemiptera: Belostomatidae, Nepidae, Notonectidae
and Pleidae, pp. 535-558 In: State fauna Series 3 : Fauna of West Bengal, Part
5, Zoological
Survey of India, Culcutta.
Bay
C.E. (1974). Predatory-Prey Relationships Among Aquatic Insects. Annual Review of Entomology 441-453pp.
Bhattacharya, D.K. (1998). Insect fauna associated with large
waterhyacinth in freshwater wetlands of West Bengal. Biodiversity and
Environment, Proceedings of the National Seminar on Environmental biology, Daya Publishing House, Delhi,
145-147pp.
Clark, F. (1992). A study of a
population of Micronecta
scutellaris Stal (Hemiptera; Corixidae) in Lake Naivasha, Kenya. Hydrobiologia 248(2): 115-114.
Chetri, G., M.S. Sheikh, J.
Kalita & A. Dutta (1997). Population abundance of aquatic insects in
Deepar Beel Assam, Insect
Environment 3(1): 14-15.
Deepa, J.
& C.A.N. Rao (2007). Aquatic Hemiptera of Pocharam Lake, Andhra
Pradesh. Zoos’ Print Journal 22(12): 2937-2939.
Jansson, A. (1987). Micronectinae
(Heteroptera, Corixidae) as indicators of water quality in Lake Vesijaervi,
southern Finland, during the period of 1976-1986. Lake
Paeijaenne Symposium, 119-128pp.
Kalita, G. (2008). Ecology and Distribution of
macroinvertebrate enmeshed fauna in Deepar wetland of Assam, India. PhD Thesis of Gauhati University, Guwahati, Assam, India.
Khan,
R.A. (2002). Diversity of freshwater
macro-invertebrate communities associated with macrophytes. Records of Zoological
Survey of India100(part 1-2): 211-228.
Merritt,
R.W. & K.W. Cummins (1996). An Introduction to the Aquatic Insets of North America. 3rd edition.
Kendall/Hunt Publishing Company, Debuque.
Ohba,
S. & F. Nakasuji (2006). Dietary items of predaceous aquatic bugs
(Nepoidea: Heteroptera) in Japanese wetlands. Limnology 7: 41-43.
Pennak, R.W. (1978). Freshwater Invertebrates of
the United States. 2nd edition. John Wiley and Sons, Inc., New York , NY, 803pp.
Rosenberg,
D.M. & V.H. Resh (1993). Introduction to freshwater biomonitoring and benthic
macroinvertebrates, pp. 195-233. In: Rosenberg, D.M. & V.H. Resh
(eds.). Freshwater Biomonitoring and Benthic Macroinvertebrates. Chapman and
Hall, New York.
Runck,
C. & D.W. Blinn (1994). Role of Belastoma bakeri (Heteroptera) in the trophic
ecology of a fishless desert spring. Limnology and Oceanography 39(8): 1800-1812.
Saha, N., G. Aditya, A. Bal & G.K. Saha (2007). A comparative study of predation of three aquatic heteropteran
bugs on Culex quinquefasciatus larvae. Limnology 8: 273-80. (Asia Ocenia Report)
Thirumalai, G. (2007). A Synoptic List of
Nepomorpha (Hemiptera: Heteroptera) from India. Zoological
Survey of India, Kolkata. Occasional Paper Number 273.
Thirumalai, G. (2002). A check listof Gerromorpha (Hemiptera) from India. Records of Zoological
Survey of India100(1-2): 55-97.
Wollmann, K. (2000). Corixidae (Hemiptera, Heteroptera) in
an acidic mining lake with pH less than or equal to E in Lusatia, Germany. Hydrbiologia 433(3): 181-183.