NOTA CIENTÍFICA

Pseudosmittia adunca & P. joaquimvenancioi (Diptera: Chironomidae), first records from Argentina

Pseudosmittia adunca & P. joaquimvenancioi (Diptera: Chironomidae), primer registro de la Argentina

 

Fuentes, María Cecilia & Melina Mauad

Instituto de Limnología Dr. Raúl A. Ringuelet (ILPLA). CONICET - CCT La Plata. FCNyM, UNLP. 122 y 60, La Plata 1900, Buenos Aires, Argentina. E-mail: cecilia.fuentes@hotmail.com.ar; melinam@ilpla.edu.ar

Recibido: 20-II-2015
Aceptado: 28-IV-2015

 

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ABSTRACT. Based on specimens of the genus Pseudosmittia recorded from two localities of the province of Buenos Aires in Argentina, the geographic distribution of P. adunca and P. joaquimvenancioi is extended. In addition, the new material of P. adunca allows us to expand its diagnosis.

KEYWORDS: Orthocladiinae; Pseudosmittia; Geographical distribution; Salado River; Punta Lara.

RESUMEN. A partir de los ejemplares del género Pseudosmittia registrados en dos localidades de la provincia de Buenos Aires (Argentina), se extiende la distribución geográfica de P. adunca y P. joaquimvenancioi. Además, el nuevo material de P. adunca nos permite ampliar su diagnosis.

PALABRAS CLAVE: Orthocladiinae; Pseudosmittia; Distribución geográfica; Río Salado; Punta Lara.

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Pseudosmittia Edwards, 1932 is one of the largest and diverse genera within the Orthocladiinae, with worldwide distribution. Their representatives present terrestrial or semi-terrestrial habits and can be found on the borders of swamps, ponds and streams with vegetation (Epler, 2001). Andersen et al. (2010) reviewed this genus in the Neotropics, establishing 23 species and one morphotype. Later, Mauad et al. (2013) described a new Pseudosmittia species occurring in the pampean biogeographical province of Cabrera & Willink (1973).

Based on material collected in two localities of Buenos Aires province in Argentina, the geographic distribution of Pseudosmittia adunca Andersen et al. and P. joaquimvenancioi (Messias & Oliveira) is expanded. Furthermore, the study of the new specimens of P. adunca allows us to expand its diagnosis.

The studied specimens were mounted in Canada balsam following the procedures described by Paggi (2009). Morphological terminology and measurement standards follow Sæther (1980). The material is housed in the collection of the Museo de La Plata, Argentina (MLP).

Pseudosmittia joaquimvenancioi (Messias & Oliveira, 2000)

Material examined. ARGENTINA: Buenos Aires Province, Junín, Río Salado, 34° 37' 12.6'' S- 60° 58' 05.1'' W, 30-III-2011, Sweep net, Donato,M. & Siri, A.cols, 1 male (MLP).

Comments. Pseudosmittia joaquimvenancioi is common in the Neotropical Region, the geographical distribution for this species is extended from Mexico, Costa Rica, Venezuela and Brazil (Andersen et al., 2010). New material collected in Argentina allows us to extend its distribution to Buenos Aires, down to Río Salado as the southern border.

The Salado River, located at north-centre of Buenos Aires province is the most important effluent of Rio de La Plata catchment. It is characterized by high concentrations of phosphates and phytoplanktonic species showing the river's eutrophication (Gabellone et al., 2005, 2013). The disturbance of this river could be related to the surrounding agricultural practice and to the waste waters from the urban area that flow into it. P. joaquimvenancioi is frequent in this kind of environments, since it has always been found at areas that displayed some kind of disturbance such as agriculture, urbanization, sedimentation, etc.

Pseudosmittia adunca Andersen et al., 2010

Material examined. ARGENTINA: Buenos Aires Province, Reserva Natural Integral Mixta Punta Lara, El Zanjón, 34° 47' 33.8'' S- 57° 59' 52.5'' W, 7-VIII-2013, Sweep net, Donato, M. col, 9 males (MLP).

Male (n=5 except when otherwise stated)

Total length 1.8-2.17 mm. Thorax length 0.55-0.75 mm. Abdomen length 1.23-1.42 mm. Total length/wing length 1.41-1.79 mm, wing length/profemur length 2.84-3.30 mm.

Head. AR 0.97-1.07. Antenna with 13 flagellomeres. Terminal flagellomere 339-370 µm long. Tentorium 112-124 µm long and 17-20 µm wide. Stipes 90-124 µm long and 6-6 µm wide. Five inner vertical setae; clypeus with 5-11 setae. Length of palpomeres (1-5): 20-26 µm, 32- 36 µm, 62-74 µm, 72-78 µm, 90-110 µm.

Thorax. Antepronotum with 1 lateral seta. Acrostichals 2. Dorsocentrals 8-10; prealars 4; supraalar 0. Scutellum with 6-7 setae.

Wing. Length 1.12-1.28 mm. VR 1.35-1.49.

Brachiolum with 1 seta, other veins bare.

Legs. Width at apex of front tibia 22-27 µm; of middle tibia 22-30 µm; of hind tibia 22-37 µm. Lengths and proportion of legs in Table 1.

Table 1. Lengths (in µm) and proportions of legs of Pseudosmittia adunca (male, n = 5). Abbreviations: Femur (fe); Tibia (ti); Tarsomeres 1-5 (Ta_1-5); Leg Ratio (LR), ratio of metatarsus to tibia; "Beinverhaltnisse" (BV), combined length of femur, tibia, and basitarsus divided by combined length of tarsomeres 2-5; "Schenkel-Scheine-verhältnis" (SV), ratio of femur plus tibia to metatarsus.

Hypopygium. Anal point 16-25 µm long, tergite IX with 14-16 setae. Laterosternite IX with 3-4 setae. Phallapodeme 64-95 µm long; transverse sternapodeme 54-65 µm long. Virga 18-24 µm long.

Gonocoxite 145-186 µm long. Superior volsella 37-44 µm long. Median volsella double; dorsal lobe bare, projecting anteriomedially, 45-50 µm long; ventral lobe projecting posteriomedially, fringed with strong microtrichia, 40-42 µm long. Inferior volsella double, anterior lobe 10-16 µm long (4); median lobe with fringe of strong microtrichia at apex, 20-27 µm long. Gonostylus 54-60 µm long, megaseta 10-14 µm long. HR 2.64-3.26; HV 3.33-3.62.

Comments. Thus far, Pseudosmittia adunca has been mentioned only for two localities of Santa Catarina State in northeast Brazil (Andersen et al, 2010). From the new material incorporated in this work, we can extend the geographic distribution of this species, and establish Punta Lara Reserve (Buenos Aires, Argentina) as its southernmost distribution.

Punta Lara Reserve has been of great interest for numerous scientists and naturalists long before its incorporation to the System of Protected Natural Areas of Buenos Aires province in 2007. This interest can be attributed to the habitat heterogeneity (rain forest, grasslands and wetlands) that encourages high diversity of floristic and faunistic species, and also to the cultural and historical importance of the location.

The Reserve has many animal and plant species that also occur in the Paranean rain forest of northeastern Argentina and Brazil. Across the Uruguay and Paraná rivers, the rain forest reaches its southernmost distribution in Punta Lara (Cabrera & Dawson, 1944). The species P. adunca is one of the so many species that shows this distributional pattern.

ACKNOWLEDGEMENTS

We would like to thank park ranger Juan Pablo Carricart of the Reserva Natural Integral Mixta Punta Lara. We also thank Mariano Donato for his contributions and suggestions. This paper is the Scientific Contribution Nº 960 of the Institute of Limnology "Dr. R. A. Ringuelet" (ILPLA, CCT-La Plata, CONICET, UNLP).

LITERATURE CITED

1. ANDERSEN, T., O. A. SAETHER & H. F. MENDES. 2010. Neotropical Allocladius Kieffer, 1913 and Pseudosmittia Edwards, 1932 (Diptera: Chironomidae). Zootaxa 2472: 1-77.         [ Links ]

2. CABRERA, A. & A. WILLINK. 1980. Biogeografía de América Latina. Organización de Estados Americanos. Serie de Biología. Monografia No. 13, Washington D.C.         [ Links ]

3. CABRERA, A. L. & G. DAWSON. 1944. La Selva Marginal de Punta Lara en la Ribera Argentina del Río de La Plata. Revista del Museo de La Plata, Sección Botánica 5 (22): 267-382.         [ Links ]

4. EPLER, J. H. 2001. Identification manual for the larval Chironomidae (Diptera) of North and South Carolina. A guide to the taxonomy of the midges of the 200 southeastern United States, including Florida. Special Publication SJ2001-201 SP13, North Carolina. http://home.earthlink.net/~johnepler/index.html        [ Links ]

5. GABELLONE, N. A., M. C. CLAPS, L. C. SOLARI & N. C. NESCHUK. 2005. Nutrients, conductivity and plankton in a landscape approach to a Pampean saline lowland river (Salado River, Argentina). Biogeochemistry 75: 455-477.         [ Links ]

6. GABELLONE, N. A., M. C. CLAPS, L. C. SOLARI, N. C. NESCHUK & D. M. ARDOHAIN. 2013. Spatial and temporal distribution pattern of phosphorus fractions in a saline lowland river with agricultural land use (Salado River, Buenos Aires, Argentina). Fundamental and Applied Limnology 183(4): 271-286.         [ Links ]

7. MAUAD, M., M. DONATO & A. SIRI. 2013. New species of Pseudosmittia Edwards, 1932 and new records of Allocladius Kieffer, 1913 (Diptera: Chironomidae, Orthocladiinae) from South America. Zootaxa 3694: 445-460.         [ Links ]

8. PAGGI, A. C. 2009. Diptera. Chironomidae. In: Domínguez, E. & H. R. Fernández (eds.), Macroinvertebrados Bentónicos Sudamericanos. Sistemática y Biología, Fundación Miguel Lillo, Tucumán, pp. 383-409.         [ Links ]

9. SÆTHER, O. A. 1980. Glossary of chironomid morphology terminology (Diptera: Chironomidae). Entomologica Scandinavica Supplement 34: 1-532.         [ Links ]