The burrows of Parastacus defossus (Decapoda: Parastacidae), a fossorial freshwater crayfish from southern Brazil
Parastacus defossus Faxon, 1898 is a fossorial crayfish species, which constructs its burrows in swampy areas in southeast Uruguay and in the state of Rio Grande do Sul, Brazil. The present field study was carried out in Lami, Porto Alegre, Rio Grande do Sul, Brazil, from May 2003 through August 200...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Sociedade Brasileira de Zoologia
2010-06-01
|
| Series: | Zoologia (Curitiba) |
| Subjects: | |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702010000300004 |
| _version_ | 1797966265602539520 |
|---|---|
| author | Clarissa K. Noro Ludwig Buckup |
| author_facet | Clarissa K. Noro Ludwig Buckup |
| author_sort | Clarissa K. Noro |
| collection | DOAJ |
| description | Parastacus defossus Faxon, 1898 is a fossorial crayfish species, which constructs its burrows in swampy areas in southeast Uruguay and in the state of Rio Grande do Sul, Brazil. The present field study was carried out in Lami, Porto Alegre, Rio Grande do Sul, Brazil, from May 2003 through August 2005. Environmental measurements (temperature, pH, dissolved oxygen, and water-table depth) of the water in the galleries were made monthly. Burrow morphology was analyzed by means of resin and gypsum casts. The spatial distribution and changes in the number and shape of the surface openings over time were observed in a 100 m² area. To estimate the spatial distribution of the openings, the observed distribution was compared with the expected distribution predicted by the Poisson and Negative Binomial frequency-distribution models. The adult population density was estimated by direct observation of burrows and counts in the study area. Inside the burrows of P. defossus, the water temperature ranged between 16.6°C (autumn 2004) and 23°C (spring 2003). The water was hypoxic and slightly acidic, and the dissolved oxygen content was very low (mean 1.43 mg/l) (18.2% saturation). The soil with burrows had higher percentages of coarse sand, fine sand, and silt. The spatial distribution of the openings showed a significant fit to the Negative Binomial distribution, indicating that the distribution of the openings is aggregated, as confirmed from the burrow morphology. The galleries are always formed by a central tunnel with multiple branchings that connect the underground water to the soil surface by one or more openings, which can be recognized by the chimneys. From knowledge of the burrow morphology, the population density was estimated to be about 120 individuals/100 m². |
| first_indexed | 2024-04-11T02:13:01Z |
| format | Article |
| id | doaj.art-85cf46d22aa34be386bcb5bdabe4ef39 |
| institution | Directory Open Access Journal |
| issn | 1984-4670 1984-4689 |
| language | English |
| last_indexed | 2024-04-11T02:13:01Z |
| publishDate | 2010-06-01 |
| publisher | Sociedade Brasileira de Zoologia |
| record_format | Article |
| series | Zoologia (Curitiba) |
| spelling | doaj.art-85cf46d22aa34be386bcb5bdabe4ef392023-01-03T01:49:12ZengSociedade Brasileira de ZoologiaZoologia (Curitiba)1984-46701984-46892010-06-0127334134610.1590/S1984-46702010000300004The burrows of Parastacus defossus (Decapoda: Parastacidae), a fossorial freshwater crayfish from southern BrazilClarissa K. NoroLudwig BuckupParastacus defossus Faxon, 1898 is a fossorial crayfish species, which constructs its burrows in swampy areas in southeast Uruguay and in the state of Rio Grande do Sul, Brazil. The present field study was carried out in Lami, Porto Alegre, Rio Grande do Sul, Brazil, from May 2003 through August 2005. Environmental measurements (temperature, pH, dissolved oxygen, and water-table depth) of the water in the galleries were made monthly. Burrow morphology was analyzed by means of resin and gypsum casts. The spatial distribution and changes in the number and shape of the surface openings over time were observed in a 100 m² area. To estimate the spatial distribution of the openings, the observed distribution was compared with the expected distribution predicted by the Poisson and Negative Binomial frequency-distribution models. The adult population density was estimated by direct observation of burrows and counts in the study area. Inside the burrows of P. defossus, the water temperature ranged between 16.6°C (autumn 2004) and 23°C (spring 2003). The water was hypoxic and slightly acidic, and the dissolved oxygen content was very low (mean 1.43 mg/l) (18.2% saturation). The soil with burrows had higher percentages of coarse sand, fine sand, and silt. The spatial distribution of the openings showed a significant fit to the Negative Binomial distribution, indicating that the distribution of the openings is aggregated, as confirmed from the burrow morphology. The galleries are always formed by a central tunnel with multiple branchings that connect the underground water to the soil surface by one or more openings, which can be recognized by the chimneys. From knowledge of the burrow morphology, the population density was estimated to be about 120 individuals/100 m².http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702010000300004Burrow morphologycrayfishgalleries |
| spellingShingle | Clarissa K. Noro Ludwig Buckup The burrows of Parastacus defossus (Decapoda: Parastacidae), a fossorial freshwater crayfish from southern Brazil Zoologia (Curitiba) Burrow morphology crayfish galleries |
| title | The burrows of Parastacus defossus (Decapoda: Parastacidae), a fossorial freshwater crayfish from southern Brazil |
| title_full | The burrows of Parastacus defossus (Decapoda: Parastacidae), a fossorial freshwater crayfish from southern Brazil |
| title_fullStr | The burrows of Parastacus defossus (Decapoda: Parastacidae), a fossorial freshwater crayfish from southern Brazil |
| title_full_unstemmed | The burrows of Parastacus defossus (Decapoda: Parastacidae), a fossorial freshwater crayfish from southern Brazil |
| title_short | The burrows of Parastacus defossus (Decapoda: Parastacidae), a fossorial freshwater crayfish from southern Brazil |
| title_sort | burrows of parastacus defossus decapoda parastacidae a fossorial freshwater crayfish from southern brazil |
| topic | Burrow morphology crayfish galleries |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702010000300004 |
| work_keys_str_mv | AT clarissaknoro theburrowsofparastacusdefossusdecapodaparastacidaeafossorialfreshwatercrayfishfromsouthernbrazil AT ludwigbuckup theburrowsofparastacusdefossusdecapodaparastacidaeafossorialfreshwatercrayfishfromsouthernbrazil AT clarissaknoro burrowsofparastacusdefossusdecapodaparastacidaeafossorialfreshwatercrayfishfromsouthernbrazil AT ludwigbuckup burrowsofparastacusdefossusdecapodaparastacidaeafossorialfreshwatercrayfishfromsouthernbrazil |