Life history of gnathiid isopods-current knowledge and future directions

Life history traits expressed by organisms vary due to ecological and evolutionary constraints imposed by their current environmental conditions and genetic heritage. Trematodes often alter the life history of their host snails by inducing parasitic castration. Our understanding of the variables that influence the resulting changes in host growth, fecundity and survivorship is insufficient to confidently predict specific outcomes of novel snail–trematode combinations. In a literature review of the last 30 years, we found 41 publications examining various life history characteristics of trematode-infected snails. These publications reported 113 different field and laboratory experiments involving 30 snail species and 39 trematode species and provided a data set for assessing factors that potentially affect life history outcomes. Analysis of the diverse responses across various snail–trematode systems and experimental conditions teased out general patterns for the expression of host growth, fecundity and survival. These were used to address existing hypotheses and develop several new ones relating the response of snail-trematode interactions to environmental and genetic factors. Finally, we propose directions for future experiments that will better assess the ecological and evolutionary factors influencing snail life history responses to trematode parasitism.

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A Review on the Study of Cyanotoxins in Paleolimnological Research: Current Knowledge and Future Needs

Toxins ◽

10.3390/toxins12010006 ◽

2019 ◽

Vol 12 (1) ◽

pp. 6 ◽

Cited By ~ 6

Author(s):

Eliana Henao ◽

Piotr Rzymski ◽

Matthew Waters

Keyword(s):

Biomedical Applications ◽

Current Knowledge ◽

Sediment Cores ◽

Future Research ◽

Sedimentary Pigments ◽

Direct Extraction ◽

Future Directions ◽

Cyanobacterial Toxin ◽

History Of

Cyanobacterial metabolites are increasingly studied, in regards to their biosynthesis, ecological role, toxicity, and potential biomedical applications. However, the history of cyanotoxins prior to the last few decades is virtually unknown. Only a few paleolimnological studies have been undertaken to date, and these have focused exclusively on microcystins and cylindrospermopsins, both successfully identified in lake sediments up to 200 and 4700 years old, respectively. In this paper, we review direct extraction, quantification, and application of cyanotoxins in sediment cores, and put forward future research prospects in this field. Cyanobacterial toxin research is also compared to other paleo-cyanobacteria tools, such as sedimentary pigments, akinetes, and ancient DNA isolation, to identify the role of each tool in reproducing the history of cyanobacteria. Such investigations may also be beneficial for further elucidation of the biological role of cyanotoxins, particularly if coupled with analyses of other abiotic and biotic sedimentary features. In addition, we identify current limitations as well as future directions for applications in the field of paleolimnological studies on cyanotoxins.

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Size-dependent shell growth and survival in natural populations of the rock-dwelling land snail Chondrina clienta

Canadian Journal of Zoology ◽

10.1139/cjz-2014-0307 ◽

2015 ◽

Vol 93 (5) ◽

pp. 403-410 ◽

Cited By ~ 4

Author(s):

Dénes Schmera ◽

Anette Baur ◽

Bruno Baur

Keyword(s):

Life History ◽

Current Knowledge ◽

Shell Growth ◽

Shell Height ◽

Survival Rates ◽

Natural Populations ◽

Land Snails ◽

Snail Species ◽

Size Dependent ◽

History Of

Rock-dwelling land snails, feeding on algae and lichens that grow on stone surfaces, may influence the structure and function of these ecosystems. Yet, little is known about the life history of rock-dwelling snails. We performed a 30-month mark–release–resight study in four populations of Chondrina clienta (Westerlund, 1883) inhabiting vertical walls of abandoned limestone quarries on the Baltic island of Öland, Sweden, to assess growth rate and survival of juvenile snails and determine age at maturity. We marked 800 individuals ranging in shell height from 1.4 to 4.9 mm, released them in their original habitat, and remeasured their shell height at intervals of 6 months. Shell growth of juvenile C. clienta was affected by the site (quarry wall) and the size of the individual, being highest in medium-sized snails. Shell growth occurred during both summer and winter. Annual apparent survival rates of C. clienta were size-dependent and ranged from 58.6% to 96.3%. Sexual maturity was reached at an age of 5 years, which is later than in most large snail species. Our study extends current knowledge on life history of land snails to a rarely studied group dwelling on rock surfaces.

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Review and consideration on habitat use, distribution and life history of Lycengraulis grossidens (Agassiz, 1829) (Actinopterygii, Clupeiformes, Engraulididae)

Biota Neotropica ◽

10.1590/s1676-06032013000300015 ◽

2013 ◽

Vol 13 (3) ◽

pp. 121-130 ◽

Cited By ~ 11

Author(s):

Ana Cecilia Giacometti Mai ◽

João Paes Vieira

Keyword(s):

Life History ◽

Habitat Use ◽

Current Knowledge ◽

Atlantic Coast ◽

Local Population ◽

High Plasticity ◽

Southwest Atlantic ◽

Coastal Fish ◽

History Of ◽

Shrimp Fisheries

In this paper, we present a summary of the current knowledge of Lycengraulis grossidens, a widely distributed coastal fish that occurs from Belize to Argentina. This species is abundant in estuaries along the Southwest Atlantic Coast and is important for recreational fishing, and as bycatch of shrimp fisheries. We compiled data available on taxonomy, phylogeny, ecology, fisheries and organized conceptually the life cycle of the species according to modern estuarine-use classification. Our review showed that along its geographic distribution and inside some particular environments (i.e., estuaries and costal lagoons) the species have been classified in a variety of ways in order to describe the remarkable complexity of habitat use that varies from freshwater resident, anadromous, marine migrant, estuarine resident, marine stragglers, catadromous to semi-catadromous. We conclude that L. grossidens is able to reproduce either in freshwater or estuarine water and postulate that it has a high plasticity in habitat use and life history, with migratory and resident contingents in the same local population. There seems to be a latitudinal change in migratory behavior of this species along the South America Coast, prevailing anadromous or semi-anadromous pattern at higher latitudes and marine migrants at the tropical northeast coast of Brazil.

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