First record of Synchaeta jollyae (Shiel and Koste, 1993) (Rotifera) in the Neotropical region: Furnas Reservoir, MG, Brazil

NOTES AND COMMENTS

First record of Synchaeta jollyae (Shiel and Koste, 1993) (Rotifera) in the Neotropical region: Furnas Reservoir, MG, Brazil

Negreiros, NF.I, ^*; Santos, RM.^I; Silva, LC.^I; Rocha, O.^II; Santos-Wisniewski, MJ.^III

^IPrograma de Pós-graduação em Ecologia e Recursos Naturais, Universidade Federal de São Carlos - UFSCar, Rod. Washington Luis, Km 235, CP 676, CEP 13565-905, São Carlos, SP, Brazil

^IIDepartamento de Ecologia e Biologia Evolutiva, Universidade Federal de São Carlos - UFSCar, Rod. Washington Luis, Km 235, CP 676, CEP 13565-905, São Carlos, SP, Brazil

^IIIDepartamento de Biologia, Universidade Federal de Alfenas - UNIFAL-MG, Rua Gabriel Monteiro da Silva, 714, CEP 37130-000, Alfenas, MG, Brazil

The Synchaetidae (Rotifera, Monogononta) are represented by 4 genera, being Synchaeta the most representative. There are 34 species known for this genus, 7 of them occurring in the Neotropical region: Synchaeta arcifera Xu, 1998; S. kitina kitina Rousselet, 1902; S. longipes Gosse, 1887; S. oblonga Tessin, 1890; S. pectinata Ehrenberg, 1832; S. stylata Wierzejski, 1893; S. tremula (Müller, 1786) (Segers, 2007). This genus was initially described by Rousselet (1902) who included detailed descriptions of the species trophy, a relevant contribution to the taxonomical work, according to Nogrady and Segers (2002).

Populations of Synchaeta sp. were abundant in the zooplankton community in Furnas Reservoir, an oligotrophic system (46° 19' W and 20° 40' S), during the period between August 2006 and July 2007. Among them Synchaeta jollyae, a species not yet reported for the Neotropical region, occurred in large numbers. Therefore, the aim of this short communication is to report the first occurrence of this species in the Neotropical region, in Brazil and Minas Gerais state.

A total of 317 individuals taken from different samples were measured with an optical microscope Olympus BX50 (up to 2000 times magnification). The observation of the trophi - required for the identification at the species level for non-loricated rotifers, was performed after adding sodium hypochloride 1% solution to the specimens directly on the glass slide, as recommended by Paggi (1995). The taxonomical identification was based on descriptions by Shiel and Koste (1993) and Nogrady and Segers (2002).

Individuals of the population examined had body lengths ranging from 140 to 207.5 μm and mean value of 158.1 μm, differing slightly from the 107 ± 1.8 μm reported by Shiel and Koste (1993). A distinctive characteristic of this species is the slightly convex head, a slender foot with two tiny toes (Figure 1). The trophi has long fulcrum and manubria, the latter slender with external edges supporting a long curved blade (Figure 2).

S. jollyae occurred throughout the year of study in all 6 localities sampled in the Sapucaí compartment of Furnas Reservoir reaching the maximum density of 3,370 ind. m^-3 in June 2007, sampled by vertical net hauls from depths varying between 2.6-27.0 m. Recent studies in this same reservoir reported the occurrence of S. stylata and S. tremula (Rosa, 2008) besides a third species identified only at genus level (Rosa, 2008; Castilho and Santos-Wisniewski, 2009). It is possible that these records of Synchaeta sp. could be S. jollyae populations which if confirmed, would indicate the species persistence in the reservoir.

According to Shiel and Koste (1993) S. jollyae has been recorded in Rockhampton, Queensland, and Warramba Dam (Lake Burragorang), both water bodies that are also oligotrophic systems in Australia, but they suggested that its distribution could be much more widespread. Considering that in Furnas reservoir this species was abundant and occurred throughout the year, it is possible that it occurs in other places across the Neotropical region.

Received September 30, 2010

Accepted October 27, 2010

Distributed February 28, 2011

• CASTILHO, MCA. and SANTOS-WISNIEWSKI, MJ., 2009. Diversidade da comunidade zooplanctônica na entrada dos rios Verde e Sapucaí no reservatório da UHE de Furnas - MG. In: Anais do IX Congresso de Ecologia do Brasil, 13-17 set. 2009, São Lourenço, MG.
• NOGRADY, T. and SEGERS, H., 2002. Rotifera 6. The Asplanchnidae, Gastropodidae, Lindiidae, Microcodinidae, Synchaetidae, Trochosphaeridae. In DUMONT, HJ. Guides to the identification of the microinvertebrates of the continental waters of the world 18., Dordrecht, The Netherlands: Backhuys Publishers BV. 264 p.
• PAGGI, JC., 1995. Crustacea: Cladocera: chave para determiner gêneros de cladocera registrados na region neotropical. In LOPRETTO, EC. and TELL, G., Ed. Ecossistemas de água continentales: metodologia para su estúdio. La Plata: Ediciones Sur. p. 909-951.
• ROSA, PG., 2008. Comunidade zooplanctônica de cinco reservatórios tropicais do sistema Furnas S.A. (Brasil): abundância e biomassa em carbono. Juiz de Fora: Departamento de Ecologia, Universidade Federal de Juiz de Fora. 133 p. Dissertação de mestrado em ecologia aplicada ao manejo e conservação de recursos naturais.
• ROUSSELET, C., 1902. The genus Synchaeta Journal of The Royal Society, vol. 42, p. 269-290.
• SEGERS, H., 2007. Annotated checklist of the rotifers (Phylum Rotifera), with notes on nomenclature, taxonomy and distribution Auckland, New Zealand: Magnolia Press. 144 p. Zootaxa, 1564.
• SHIEL, RJ. and KOSTE, W., 1993. Rotifera from Australian waters. IX. Gastropodidae, Synchaetidae, Asplanchnidae (Rotifera: Monogononta). Transactions of the Royal Society of South Australia, vol. 117, p. 111-139.

Publication Dates

• Publication in this collection
  11 Mar 2011
• Date of issue
  Feb 2011