This study briefly reports a newly recorded gastrotrich species, Chaetonotus (Primochaetus) heideri Brehm, 1917, which was isolated from the water sample collected from the Ramsar site Khajjiar Lake, Himachal Pradesh, India. A brief description of the Indian population, based on photomicrographs taken from live specimens, is presented here. The species is reporte

Bharti D.

Ghosh A.

Krishnan S.

Kumar S.

Todaro M. A.

English

Archivio istituzionale della ricerca - Università di Modena e Reggio Emilia

Rec. zool. Surv. India: Vol. 123(3)/255-260, 2023DOI: 10.26515/rzsi/v123/i3/2023/172377ISSN (Online) : 2581-8686ISSN (Print)  : 0375-1511* Author for correspondence Accepted on: 13.11.2023Article Received on: 30.10.2022Introduction The small acoelomate gastrotrichs are found in freshwater, marine, and brackish environments, and rarely in terrestrial soils. Currently, the number of gastrotrich species distributed globally is about 890 (Saponi & Todaro, 2024), with Chaetonotidae being the most speciose family. The group is widespread, with a density in freshwater that may reach 100,000 individuals/m2 (Balsamo & Todaro, 2002), and serves as a vital connection between the microbial loop and larger predators in the meiofauna community (Todaro & Hummon, 2008; Todaro & Luporini, 2022). Despite the early diversity of Indian freshwater gastrotrich species being as low as 25 only (Naidu & Rao, 2006), there have been few reports published throughout the decades (Annandale, 1907; Naidu, 1962; Visvesvara, 1963; Dhanapathi, 1976; Rao & Chandramohan, 1977; Sharma, 1980; Sharma, 1987; Naidu & Rao, 2004; Harkal & Mokashe, 2013). According to Bharti and Kumar (2019), the insufficient account of the biodiversity of Indian Gastrotricha is attributed, in part, to the lack of taxonomists with deep expertise on these micro metazoans. Therefore, conducting additional sampling across India and employing advanced microscopic techniques, such as DIC optics and molecular sequencing, will unveil additional species and AbstractThis study briefly reports a newly recorded gastrotrich species, Chaetonotus (Primochaetus) heideri Brehm, 1917, which was isolated from the water sample collected from the Ramsar site Khajjiar Lake, Himachal Pradesh, India. A brief description of the Indian population, based on photomicrographs taken from live specimens, is presented here. The species is reported to be common in freshwater habitats in many areas of the world and is also known to exhibit variable morphology.Keywords: Gastrotrich, Khajjiar Lake, Live Observation, Ramsar Site First record of Chaetonotus (Primochaetus) heideri (Gastrotricha, Chaetonotida) from IndiaSreerag Krishnan1, Arnab Ghosh1, Daizy Bharti1, M. Antonio Todaro2 and Santosh Kumar1*1Zoological Survey of India, ‘M’-Block, New Alipore, Kolkata – 700053, West Bengal, India; E-mail: santoshkumar@zsi.gov.in 2Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 213d, I-41125 Modena, Italyenhance the precision of redescriptions (Chatterjee et al., 2019; Chatterjee & Todaro, 2021). Material and Methods A water sample (about 150 ml) was collected from the Ramsar site Khajjiar Lake, Himachal Pradesh, India (32°32′46″N 76°03′29″E) during a survey in October 2021. The water sample was promptly examined for the presence of gastrotrichs and ciliates immediately upon arrival at the laboratory. The raw culture was maintained at room temperature (20°C) by adding a few sterile rice kernels to promote bacterial growth (Bharti & Kumar, 2019). Specimens were isolated from the water sample for observation and live photomicrography using stereo zoom (SZ2-ILST, Olympus, Japan) and bright-field (CX 43, Olympus, Japan) microscopes. In vivo measurements were conducted at magnifications ranging from 40x to 1000x. The identification was made following standard literature (Todaro et al., 2019; Balsamo et al., 2019). Results One species of gastrotricha, identified as Chaetonotus (Primochaetus) heideri Brehm, 1917, was found in freshwater samples collected from Khajjiar Lake, Vol 123(3) | 2023 | www.recordsofzsi.com Zoological Survey of India256First record of Chaetonotus (Primochaetus) heideri (Gastrotricha, Chaetonotida) from IndiaHimachal Pradesh. A brief description of the species is presented below.Taxonomic AccountPhylum GASTROTRICHA Metschnikoff, 1865Order CHAETONOTIDA Remane, 1925 Family CHAETONOTIDAE Gosse, 1864Genus Chaetonotus Ehrenberg, 1838Subgenus Primochaetus Kisielewski, 1997Chaetonotus (Primochaetus) heideri Brehm, 1917 (Figure 1A-F, 2A-G, 3A-B)Figure 1.  Photomicrographs of Chaetonotus (Primochaetus) heideri from live specimens. A-C. Specimens show the body shape and body flexibility. D. Enlarged view of the pharynx, arrowhead indicates a sensory ciliary tuft. E. Detailed view of the oral opening and sensory ciliary tufts (arrowheads). F. Posterior portion of a specimen with a thin adhesive tube. AT, adhesive tube; I, intestine; M, mouth; P, pharynx; PJ, pharyngeal junction. Scale bars: 40 μm (D, E) and 50 μm (A-C).Vol 123(3) | 2023 | www.recordsofzsi.com Zoological Survey of India 257Krishnan et al.Figure 2.  Photomicrographs of the surface scales and spines in Chaetonotus (Primochaetus) heideri from live specimens. A-C. Specimens showing the anterior (A, B) and posterior (C) scales, bearing a double anterior edge. D. Middle portion of a specimen showing ventral spines and the spined scales in the interciliary field. E-G. Enlarged views showing barbed spines. Note the barbed structure present in the middle of the spines (arrowheads in D-F). S, scales; SP, spines. Scale bars: 20 μm (C) and 40 μm (A, B).Diagnosis of the Indian population of Chaetonotus (Primochaetus) heideri Brehm, 1917: The individuals from India exhibit a bottle-to-ten-pin shape with a three-lobed head. On average, the dimensions of the Indian specimens are as follows: body length = 170 μm, body maximum width = 50 μm, head width = 40 μm, mouth diameter = 10 μm, pharynx length = 45 μm, pharynx width = 15 μm, adhesive tube length = 20 μm, posterior-dorsal scale length = 11 μm, egg length = 28 μm, Egg width = 11 μm. The body is flexible, and the cuticle is covered in scales and spines, which extend over the entire animal. The scales exhibit an anterior double edge, characteristic of the taxon, with dorsal spines increasing in length from Vol 123(3) | 2023 | www.recordsofzsi.com Zoological Survey of India258First record of Chaetonotus (Primochaetus) heideri (Gastrotricha, Chaetonotida) from Indiathe anterior to the posterior end. The spines become barbed approximately at the near-middle portion of each spine. The posterior end is furcated, and each furcal branch terminates with a thin adhesive tube. Posterior-most spines are parallel to the adhesive tubes and do not exceed the length of the tubes. Occurrence: India- (present study); Elsewhere: The species is thus far reported from U.S.A. (Emberton, 1980), Italy (Balsamo & Fregni, 1995), Sweden (Kånneby et al., 2009, 2013), Brazil (Garraffoni et al., 2010; Kånneby et al., 2013), Canada, France, Germany, Great Britain, Romania, Russia (Schwank, 1990; Kånneby, 2013), Poland (Kolicka et al., 2013, 2020), Ukraine (Trokhymchuk, 2020).Remarks: New record to Indian waters.DiscussionEarlier records of this species indicated significant morphological variability among disjunct populations (e.g., Balsamo & Fregni, 1995). In summary, the Indian population shows less morphological similarity in terms of spine structure compared to the reported morphological forms by Balsamo (1980). Since only a few specimens could be isolated from the raw culture for morphological analysis, the identification of the Indian population of Chaetonotus (Primochaetus) heideri Brehm, 1917 in the present study may be considered provisional. Therefore, a more detailed study based on morphology, especially Differential Interference Contrast (DIC) microscopy, and molecular sequence analyses could clarify the classification of the Indian population. AcknowledgementsThe authors express sincere gratitude to the Director of the Zoological Survey of India, for providing the necessary facilities to conduct the research. Financial support from the Department of Science and Technology (DST Project no C.R.G./2019/004203 to S.K.), India DST-SERB Junior Research Fellowship to Sreerag Krishnan and CSIR-India Fellowship to Arnab Ghosh is duly acknowledged.Figure 3.  Photomicrographs of Chaetonotus (Primochaetus) heideri from live specimens. A, B. Detailed view of the anterior A. Spine alignment on the ventral surface, cephalic sensory ciliary tufts (arrowheads in A) and spined scales in the interciliary field. B. Specimen showing caudal spines (arrowheads in B) and eggs. C, locomotor cilium; EG, egg; I, intestine; M, mouth. Scale bars: 20 μm (B) and 40 μm (A).Vol 123(3) | 2023 | www.recordsofzsi.com Zoological Survey of India 259Krishnan et al. ReferencesAnnandale, N. 1907. The fauna of brackish ponds at Port Canning, Lower Bengal. Records of the Indian Museum, 1: 35-43. https://doi.org/10.26515/rzsi/v1/i3/1907/163391Balsamo, M. and Fregni, E. 1995. Gastrotrichs from interstitial fresh water, with a description of four new species. Hydrobiologia, 302: 163–175. https://doi.org/10.1007/BF00027040Balsamo, M. 1980. Secondo contributo alla conoscenza dei gastrotrichi delle acque dolci italiane. Atti della Società Toscana di Scienze Naturali, 87: 97-126.Balsamo, M. and Todaro, M. A. 2002. Gastrotricha (S.D. Rundle, A.L. Robertson and J.M. Schmid-Araya eds) Freshwater Meiofauna: Biology and Ecology. Backhuys Publisher, Leiden (pp. 45-61).Balsamo, M., D’Hondt, J.-L. and Grilli, P. 2019. Chapter 7 - Phylum Gastrotricha. Thorp and Covich’s Freshwater Invertebrates (Fourth Edition), Academic Press (pp. 149-218). https://doi.org/10.1016/B978-0-12-385024-9.00007-1Bharti, D. and Kumar, S. 2019. First record of Lepidochaetus zelinkai (Gastrotricha, Chaetonotida) from India. Records of the Zoological Survey of India, 119: 474-479.Chatterjee, T. and Todaro, M.A. 2021. An annotated checklist of the chaetonotidan gastrotricha from India. Zootaxa, 5027(3): 332-350. https://doi.org/10.11646/zootaxa.5027.3.2 PMid:34811167Chatterjee, T., Priyalakshmi, G. and Todaro, M.A. 2019. An annotated checklist of the macrodasyidan Gastrotricha from India. Zootaxa, 4545(4): 495-510. https://doi.org/10.11646/zootaxa.4545.4.3 PMid:30790887Dhanapathi, M.V.S.S.S. 1976. Taxonomic notes on some gastrotrichs from coastal Andhra Pradesh. Mem. Soc. Zool. Guntur, 1: 76-78.Emberton, K.C.J. 1980. First record of Chaetonotus heideri (Gastrotricha: Chaetonotidae) in North America. The Ohio Journal of Science, 80: 156-159.Garraffoni, A.R.S., Araujo, T.Q., Lourenco, A.P. and Balsamo, M. 2010. New data on freshwater psammic Gastrotricha from Brazil. Zookeys, 60: 1–12. https://doi.org/10.3897/zookeys.60.495 PMid:21594197 PMCid:PMC3088348Harkal, A.D. and Mokashe, S.S. 2013. Record of two species of Gastrotricha from littoral epiphytic habitat of Kagzipura Lake, Aurangabad, Maharashtra, India. Research and Reviews: Journal of Ecology and Environmental Sciences, 1: 27-29.Kånneby, T. 2013. New species and records of freshwater Chaetonotus (Gastrotricha: Chaetonotidae) from Sweden. Zootaxa, 3701: 551–588. https://doi.org/10.11646/zootaxa.3701.5.3 PMid:26191602Kånneby, T., Todaro, M.A. and Jondelius, U. 2009. One new species and records of Ichthydium Ehrenberg, 1830 (Gastrotricha: Chaetonotida) from Sweden with a key to the genus. Zootaxa, 1830: 26–46. https://doi.org/10.11646/zootaxa.2278.1.2Kånneby, T., Todaro, M.A. and Jondelius, U. 2013. Phylogeny of Chaetonotidae and other Paucitubulatina (Gastrotricha: Chaetonotida) and the colonization of aquatic ecosystems. Zoologica Scripta, 42: 88-105. https://doi.org/10.1111/j.1463-6409.2012.00558.xKolicka, M., Dabert, M., Olszanowski, Z. and Dabert, J. 2020. Sweet or salty? The origin of freshwater gastrotrichs (Gastrotricha, Chaetonotida) revealed by molecular phylogenetic analysis. Cladistics, 36: Article 458e480. https://doi.org/10.1111/cla.12424 PMid:34618974Kolicka, M., Kisielewski, J., Nesteruk, T. and Zawierucha, K. 2013. Gastrotricha from the Poznan Palm House - One new subgenus and three new species of freshwater Chaetonotida (Gastrotricha). Zootaxa, 3717: 231-279. https://doi.org/10.11646/zootaxa.3717.2.7 PMid:26176105Naidu, D. S. and Rao, A. K. 2006. Singular perturbation analysis of discrete control systems. Lecture Notes in Mathematics, Volume: 1154. Naidu, K.V. 1962. Three species of gastrotrichs from fresh waters of Cuddapah, India. Annals and Magazine of Natural History, 5(13): 1-4. https://doi.org/10.1080/00222936208651207Naidu, K.V. and Rao, G.C. 2004. Gastrotricha. Fauna of India and the adjacent countries. Zoological Survey of India, Kolkata.Rao, R.K. and Chandramohan, P. 1977. New records of some Gastrotricha from India with notes on their ecology. Geobios, 4: 204-206.Saponi, F. and Todaro, M.A. 2024. Status of the Italian Freshwater Gastrotricha Biodiversity, with the Creation of an Interactive GIS-Based Web Map. Diversity, 16: 17. https://doi.org/10.3390/d16010017. Schwank, P. 1990. Gastrotricha (J. Schwoerbel and P. Zwick eds) Süsswasserfauna von Mitteleuropa. Band 3. Gastrotricha und Nemertini. Gustav Fischer Verlag, Stuttgart, Jena, New York.Vol 123(3) | 2023 | www.recordsofzsi.com Zoological Survey of India260First record of Chaetonotus (Primochaetus) heideri (Gastrotricha, Chaetonotida) from IndiaSharma, B.K. 1980. Taxonomic notes on some freshwater Gastrotricha from West Bengal, India. Hydrobiologia, 70: 265-267. https://doi.org/10.1007/BF00016769Sharma, B.K. and Sharma, S. 1987. On species of genus Lepadella (Eurotatoria Monogononta: Colurellidae) from North-Eastern India, with remarks on Indian taxa. Hydrobiologia, 147: 15-22. https://doi.org/10.1007/BF00025721Todaro, M.A. and Hummon, W.D. 2008. An overview and a dichotomous key to genera of the phylum Gastrotricha. Meiofauna Matters, 16: 3-20.Todaro, M.A. and Luporini, P. 2022. Not too big for its mouth: direct evidence of a macrodasyidan gastrotrich preyed in nature by a dileptid ciliate. The European Zoological Journal, 89(1): 785-790. https://doi.org/10.1080/24750263.2022.2095048Todaro, M.A., Sibaja-Cordero, J.A., Segura-Bermúdez, O.A., Coto-Delgado, G., Goebel-Otárola, N., Barquero, J.D., Cullell-Delgado, M. and Zotto, M.D. 2019. An introduction to the study of Gastrotricha, with a taxonomic key to families and genera of the group. Diversity, 11: 1-25. https://doi.org/10.3390/d11070117Trokhymchuk, R.R. 2020. New reports of Gastrotricha for the North-Eastern Ukraine. Zoodiversity, 54: 349–356. https://doi.org/10.15407/zoo2020.05.349Visvesvara, G. 1963. On some Gastrotricha from India with description of two new species. Annals and Magazine of Natural History, 6(13): 435-443. https://doi.org/10.1080/00222936308651379.

First record of Chaetonotus (Primochaetus) heideri(Gastrotricha, Chaetonotida) from India

https://iris.unimore.it/bitstream/11380/1332211/1/Krishnan%20et%20al.%202023-India.pdf

First record of Chaetonotus (Primochaetus) heideri(Gastrotricha, Chaetonotida) from India

Abstract

Similar works

Full text

Available Versions

Archivio istituzionale della ricerca - Università di Modena e Reggio Emilia