Topic
Mesodesmatidae
About: Mesodesmatidae is a research topic. Over the lifetime, 41 publications have been published within this topic receiving 322 citations.
Papers
TL;DR: The conservation status of this intertidal bivalve as endangered is indicated, indicating the growth rates are faster, but that the maximum length attained has decreased, and OGP is inversely correlated with the latitudinal distribution of Mesodesma populations.
Abstract: The yellow clam Mesodesma mactroides (Bivalvia: Mesodesmatidae) was once the most abundant intertidal species on the Atlantic coast of northern Argentina and an important commercial resource in South America. This study of a population inhabiting the intertidal zone of the sheltered-dissipative sandy beach Santa Teresita documents the species’ population biology, including demographic structure, growth and production during December 2004 and December 2006, and adumbrates the critical state of M. mactroides at present. A total of 3,015 M. mactroides were collected and measured, whereas individuals were found with an anterior–posterior shell length between 2 and 64 mm. A von Bertalanffy growth function with an asymptotic length (L
∞) of 85 mm and a growth constant (K) of 0.47 year−1 was established from length–frequency distributions. The longevity of the species is estimated at approximately 6 years, and instantaneous mortality rate was about three times higher than 40 years ago. Besides, this study confirmed that the overall growth performance index (OGP) is habitat-specific and can be used to group M.
mactroides and M.
donacium from different areas into temperate and upwelling species. Furthermore, OGP is inversely correlated with the latitudinal distribution of Mesodesma populations. The intertidal biomass ranged between 0.06 and 0.07 g AFDM m−2 year−1. Individual production was observed to be highest at 47 mm length (0.35 g AFDM m−2 year−1), and annual production ranged between 0.12 and 0.19 g AFDM m−2 year−1, resulting in productivity values (P/B) between 1.84 and 2.93. The comparison of the results of the present study with those of growth studies conducted on M.
mactroides 40 years ago revealed the following considerable differences in the population structure of M.
mactroides, indicating the conservation status of this intertidal bivalve as endangered: (1) present growth rates are faster, but that the maximum length attained has decreased, (2) the numbers of individuals per square metre were many times higher in the past than in the present, (3) bivalves from the present work never reached the ‘commercial size’ of 60 mm and (4) 40 years ago, the population of M.
mactroides was composed of up to three cohorts, whereas in this study, there was only one single cohort visible.
45 citations
Journal Article•
TL;DR: It is suggested that the variabilities in distribution and abundances of clams may be related to large-scale habitat characteristics rather than to small-scale textural variability.
Abstract: Monthly samples were taken from February 1 989 to January 1 990 to evalute the longshore distribution and density of the bivalve Mesodesma donacium in a dissipative beach in southern Chile. The results showed that its distribution was patchy. Adult clams were confined to the surf zone, while the vast majority of juveniles occurred in the swash zone. The highest densities of adults were found in summer and autumn (up to 159 individuals per 0.25 m' in February 1989), while the minimum occurred during winter. Juveniles had similar densities all year round (up to 16-20 individuals per 0.25 m'). Most clams collected in the surf zone had similar shell lengths (70-75 mm); those collected in the swash zone were smaller than 25 mm. No relationships were found between distribution and abundances of clams and variability in textural characteristics of the surf or swash zone. Due to the limited longshore variability in grain size and sorting of sands, it is suggested that the variabilities in distribution and abundances of clams may be related to large-scale habitat characteristics rather than to small-scale textural variability.
31 citations
Journal Article•
26 citations
TL;DR: Adults and juveniles of the infaunal bivalve, Paphies australis (pipi), were observed drifting in raid‐water, in a small harbour in northeastern New Zealand, where there was little difference in the number of pipi caught between spring and neap tides.
Abstract: Adults and juveniles of the infaunal bivalve, Paphies australis (pipi), were observed drifting in raid‐water, in a small harbour in northeastern New Zealand. The animals were buoyed up by the secretion of long mucus threads which extended out through their siphons. Quantitative information from netting experiments over a period of five months from May 1993 to September 1993, collected a total of 509 drifting pipi. These were mainly juveniles (<15 mm shell length) but a small number of adults (up to 58 mm shell length) were also collected. The numbers of pipi caught was highly variable, however, there was a trend for more drifting pipi to be caught on the flood tide (n=386) than the ebb tide (n=123). Overall there was little difference in the number of pipi caught between spring (n=263) and neap tides (n=246), however, this was heavily influenced by one neap tide in May 1993 (n=207). Three other bivalve species (Soletellina sp, Gari stangeri, Macomona lilliand) were also caught drifting. Pipi were also obs...
20 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2020 | 1 |
| 2019 | 2 |
| 2016 | 2 |
| 2015 | 4 |
| 2014 | 2 |
| 2013 | 1 |