Abnormalities in the amphids of free-living nematodes in the black sea: Is it atavism or result of a modern morpho-functional adaptation to environmental changes and the nascent process of microevolution?
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Tarih
2016
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Nova Science Publishers, Inc.
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
In this chapter we aim to summarize our long-term data (1988-2015) about the abnormalities detected in the development of the vital chemoreceptor organs (amphids) of 49 nematode species from the Black Sea. The total list of species includes 28 valid species and 21 morphotypes, systematic position of which have been identified only to genus level as well as individuals close to a valid species (cf.), however, they require further study and clarification in our view. Amphid abnormalities are characterized by a wide spectrum of appearances. Accordingly, they may have a non-standard number of elements of a species-specific form (instead of two elements they may have 1 or 3-5); one element of amphid may be underdeveloped or not have a speciesspecific form; the topography of amphids in relation to the front edge of the head and to the axis symmetry of the body may be disturbed. Anthropogenic impact on the Black Sea ecosystem is steadily increasing. Its negative effect is revealed in the extinction of species, community perturbations, serious physiological changes in organisms, resulting in different pathological phenomena. It is obvious that the occurrence of specific abnormalities in the vital organs of the same nematodes species is a result of chromosomal mutagenesis. Repeatability and the wide distribution of species with these types of abnormalities in different regions of the basin are shown in this chapter. The issues indicated in this chapter require future research: 1. what is the specific cause of the amphid abnormalities in nematodes? 2. Are these amphid abnormalities offer an advantage or a disadvantage compared to the “normal” organs for organisms inhabiting polluted ecosystems or a life under the impact of climate change? 3. Why similar morphological abnormalities are not recorded in nematodes from the other seas? Are these chemoreceptor organ abnormalities in nematodes unique for the Black Sea? 4. Is this phenomenon shows the nascent process of microevolution of nematode fauna in the Black Sea?. © 2016 Nova Science Publishers, Inc.
Açıklama
Anahtar Kelimeler
Anomalies, Black sea, Chemoreceptor organ, Marine nematodes, Morphology
Kaynak
Baltic and Black Sea: Ecological Perspectives, Biodiversity and Management
WoS Q Değeri
Scopus Q Değeri
N/A
