Comparison of life history traits of Tanais dulongii (Tanaidacea: Tanaididae) in natural and artificial marine environments of the south-western Atlantic

Abstract

Tanaidaceans are small benthic crustaceans with a strictly benthic life cycle and low dispersion rates, so they are good candidates to evaluate the effects of environment over life history strategies and reproductive biology. In this work, we studied two populations of Tanais dulongii (Audouin, 1826) that live in two contrasting habitats in order to determine whether they differ in life history traits. The animals were obtained by systematic sampling in a rocky shore with a lower anthropic impact (La Estafeta: LE) and a polluted area (Mar del Plata harbour: MdP) from March 2011 to March 2012. Seawater temperature and salinity did not differ between sites, but MdP showed more acid and hypoxic conditions than LE. Population density was homogeneous and lower in MdP (ca. 20 ind/100 gr) than that in LE where density varied between 250 and 800 ind/100 gr. Reproductive individuals and juveniles were always present, and both populations showed two main recruitment periods: the first in spring in both populations, and the second in summer in MdP but in autumn-winter in LE. In both populations, sex ratio was strongly female-biased. Juveniles, females and males from LE had larger sizes than that from MdP and reached their sexual differentiation at larger sizes. The estimated lifespan was about 9 and 12 months in MdP and LE, respectively. This study suggests that the differences observed between populations of T. dulongii in life history traits are intimately related to environmental differences in pH and dissolved oxygen between habitats, but should not be discarded a synergistic effect of temperature, organic pollution, food availability and predation pressure.

Two new nonindigenous isopods in the Southwestern Atlantic: Simultaneous assessment of population status and shipping transport vector

“…Abundances of both species in the port follow a seasonal pattern, characterized by peaks in the summer and early autumn, and low values throughout the cold season. This pattern most probably reflects the effect of the temperature, which is the primary factor modulating the populations of other well established NIS and cryptogenic species in Mar del Plata port, such as the amphipods Monocorophium acherusicum (Costa, 1853) and Ericthonius brasiliesis (Dana, 1853), the isopod S. serratum and the tanaidacean Tanais dulongii (Audouin, 1826) (Kittlein, 1991;Rumbold et al, 2015bRumbold et al, , 2016Rumbold et al, , 2017. Given that hull surveys were conducted during the winter, higher abundances of D. edwardsi and P. sculpta than observed here should be expected during warm months.…”

DNA barcode, taxonomic and ecological notes for the identification of the invasive amphipodMonocorophium acherusicum(Costa, 1851)

“…Previous work on crustaceans found DNA barcoding to be a useful tool for specimen determination in both marine and estuarine amphipod species (Costa et al 2009;Radulovici et al 2009;Rumbold et al 2015a). Most genetic analyses of species boundaries, especially in crustaceans, reveal the existence of cryptic species, some of which are distinguished by surprisingly large genetic differences given their morphological similarity (Palumbi and Benzie 1991;Bucklin et al 1995;Knowlton and Weigt 1998;Sarver et al 1998) such as corophiids (eg Monocorophium acherusicum, M. insidiosum and Crassicorophium bonellii).…”

“…Furthermore, the identification difficulties mentioned have led to an erroneous report of M. acherusicum as M. insidiosum (see Albano and Obenat 2009). In recent years, the use of molecular taxonomy has proved to be a powerful tool for solving the misidentification of morphologically similar species (eg Bucklin et al 2007;Hou et al 2007;Bilgin et al 2015;Rumbold et al 2015a). It was also has been used to document species introductions (Bourlat et al 2013).…”

Macrozoobenthic community structure in subtidal soft-bottom area along the coast of Lembeh Island -North Sulawesi

“…Walaupun (Johnson dan Attramadal, 1982;Rumbold et al, 2012Rumbold et al, , 2015. Kepadatan Tanais dulongii lebih tinggi di daerah dengan dampak antropogenik rendah dari pada di daerah terpolusi (Rumbold et al, 2015).…”

“…Walaupun (Johnson dan Attramadal, 1982;Rumbold et al, 2012Rumbold et al, , 2015. Kepadatan Tanais dulongii lebih tinggi di daerah dengan dampak antropogenik rendah dari pada di daerah terpolusi (Rumbold et al, 2015). Tanaid dapat mencapai kepadatan hingga 5000 individu per m 2 (Kneib,1992), bahkan dapat mencapai 35000 individu/m 2 pada periode puncak pemijahan (Rumbold et al, 2012).…”