Record of Two Species of Gastrotricha from Littoral Epiphytic Habitat of Kagzipura Lake, Aurangabad, Maharashtra, India.

Abstract

Gastrotricha is generally less studied phylum in India and information about its diversity and density is scanty. The present paper reports occurrence of Polymerurus nodicaudus and Chaetonotus elegans species of Gastrotricha in periphytic habitat of Kagzipura Lake, District Aurangabad, Maharashtra. This is the first report on gastrotrich from this region.

Keywords

Gastrotricha, Polymerurus, Chaetonotus etc.

Introduction

Gastrotricha are aquatic micro invertebrates (<1 mm) with a worldwide distribution in freshwater, estuarine, and marine benthic habitats where they are an important component of the benthos and periphytic habitats [1,2,3]. According to Ruppert [4], Phylum Gastrotricha consists of about 750 species. The phylum Gastrotricha has a cosmopolitan distribution with densities up to 100.000 individuals per m² [5,6]. Gastrotricha are divided into two orders, Macrodasyida and Chaetonotida on the basis of morphological and Biological characteristics. This phylum is insufficiently known because of their microscopic size, the fragility of the body and the consequent difficulty of study [7].

According to Tonapi [8], Indian gastrotrich although one of the most common freshwater organisms is not justifiable on any account. No worthwhile work has been done on these smallest metazoans in this vast country. Very little is known regarding the distribution of different species of freshwater Gastrotricha in India. The previous workers on Gastrotricha in India are Stewart [8], Naidu [9], Dhanapathi [10], Rao and Chandra Mohan [11], Visvesvara [12,13] and Sharma [14]. As per the reviewed literature about 23 species are recorded from India.

Materials and Methods

Kagzipura Lake which is located between latitude 190 57’ N and longitude 75o 15’ E near Kagzipura village about 20 Km from Aurangabad. In this study, the periphytic samples like epiphytic, epixylic and epilithic were collected for micro invertebrates. Gastrotricha were found associated with macrophytes which are collected by picking up method developed by Masataka et.al [15].

In brief, the lake water was filtered with the help of 40μ mesh-net to avoid contamination of free living micro invertebrates. The filtered water is poured into about 1litre polythene bags. Macrophytes are cut with the help of scissors, picked up and placed in polythene bags. Leaves were script into water and primary observations were made under dissecting microscope. Gastrotricha are segregated and preserved in 4% formalin and stained with the help of Rose Bengal stain. Samples were mounted in glycerol and observed under compound microscope at high resolution for taxonomic identification.

In the present study two species of Gastrotricha are recorded, namely Polymerurus nodicaudus and Chaetonotus elegans.

Polymerurus nodicaudus

• Polymerurus nodicaudus is about 262 to 278 μ long.

• Body is slender and three lobed head with a well developed Kephalion.

• P. nodicaudus is typical periphytic and cosmopolitan in distribution. Previously it is recorded from Europe, South and North America and Asian countries like Japan, Korea, Israel and India.

Chaetonotus elegans

• The total length of body id about 150 to 165 μ.

• Body is slender and two longer spines at the end of each lateral row of spines.

• The head is five lobed, with well developed Kephalion and four tufts of short cilia.

This is the first report of Gastrotricha from Marathwada region. Understanding diversity and distribution of this group in freshwaters of India is less. These types of studies will helpful to understand the freshwater biota of this region.

References

1. Hochberg and Litvaitis. Phylogeny of Gastrotricha: a morphology-based framework of gastrotrich relationships. The Biological Bulletin. 2000; 198:299–305.
2. Balsamo and Todaro. Gastrotricha. – Pp. 45–61 in Rundle S. D., A. I. Robertson & J. M. Schmid-Araya (eds): Freshwater Meiofauna: Biology and Ecology. Backhuys Publisher, Leiden, 2000, 369 pp.
3. Balsamo M, JL d’Hondt, J Kisielewski, L Pierboni. Global diversity of gastrotrichs (Gastrotricha) in fresh waters. Hydrobiologia. 2008;595: 85–91.
4. Ruppert EE. 1991 Gastrotricha. – Pp. 41-109 in Harrison F. W. & E. E. Ruppert (eds): Microscopic Anatomy of Invertebrates. Vol. IV. Aschelminthes, Wiley-Liss, New York.
5. Nesteruk T. Density and biomass of Gastrotricha in sediments of different types of standing waters Hydrobiologia. 1996;324:205-328.
6. Nesteruk T. Species composition and dominance structure of Gastrotricha assemblages in water bodies of different trophic status. Hydrobiologia. 1996;339:141-148.
7. Ricci C, M Balsamo. The biology and ecology of lotic Rotifers and gastrotrichs. Freshwater Biology. 2000 44: 15–28.
8. Stewart FW. Rotifers and Gastrotricha from Tibet. Rec. Indian museum. 1908;2:316-323.
9. Vanamala Naidu. Three species of Gastrotrichs from fresh Waters of Cuddapah, India. Ann Mag Nat Hist. 1962;(13)5 : 1 -4 .
10. Rao RK, Chandra Mohan P. New records of some gastrotriches from India with notes on their ecology. Geobios. 1977;4: 204-206.
11. Dhanapathi MVSSS. Taxonomic notes on some Gastrotrichs from coastal Andhra Pradesh. Mem Soc Zool Guntur. 1976; 1:76-78.
12. Visvesvara G. On some Gastrotricha from India with description of two new species ann. Ann Mag Nat Hist. 1963;6(13):435-443.
13. Visvesvara G. on some Gastrotricha of genus Chaetonotus from India. Amnn mag. Nat Hist 1964;7(13):209- 216.
14. Sharma BK. Taxonomic notes on some freshwater gastrotrichs from West Bengal. Hydrobiologia. 1980; 70: 265- 267.
15. Masataka S, Takayuki H, Ryoji N, Hiroki H. Methods for quantitative sampling of epiphytic microinvertebrates in lake Vegetation. Limnology. 2002;3:115–119.