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Preliminary Observations on Nematodes from Coastal Patagonian
Sediments (Chubut, Argentina)
Russo, V.L. & C.T. Pastor
Centro Nacional Patagónico (CONICET). C.C. 128 (9120) Puerto Madryn, Chubut. Argentina
This paper focuses on two new species belonging to Neochromadora (CHROMADORIDAE)
and Cobbia (MONHYSTERIDAE), two very cosmopolitan genera inhabiting coastal
sediments systems, providing their distribution on East coastal Patagonia.
Seven littoral areas have been sampled at three latitudes. The samples have been fixed in 5%
formalin with rose Bengal in the field. The geographical position (GPS), salinity,
temperature, granulometry, organic matter, DPR layer and dissolved Oxygen have been
taken. Nematodes were extracted using the elutriation/decantation/LUDOX TM method and
specimens mounted on slides.
The Nematodes found were identified up to the lowest taxonomy level possible, and
photographs were taken using a Photomicroscope. For nematode identifications the keys of
Platt & Warwick and Warwick et al. were used.
Two probably new species belonging to this two genera are described from Patagonian
coastal areas, Chubut province of Argentina: Neochromadora sp. is characterized by
gubernaculums and spicules shape, the presence of a thick cuticle plate on subventral tail
area; esophageal bulb shape and length of cephalic and somatic setae. It has been found in
upper to low littoral sandy areas. Cobbia sp. is characterized by the amphid position and size
and length of cephalic setae. It has been found in low littoral sandy beaches.
These species have been described in the project titled: ‘Biodiversity of meiofauna
communities in sand beaches of Río Negro and Chubut’ supported by -GEF- Secretaría de
Medio Ambiente de Nación- CONICET, Argentina.
5 th International Congress of Nematology, 2008 233