Karyotypes of operculate land snails of the genusCyclophorus(Prosobranchia: Cyclophoridae) in Thailand

Molecular Evidence for Cryptic Speciation in the Cyclophorus fulguratus (Pfeiffer, 1854) Species Complex (Caenogastropoda: Cyclophoridae) with Description of New Species

“…For molecular analysis, the 46 live specimens of C. fulguratus from 23 localities, including the voucher specimens from previous studies of Kongim et al (2006) [23] , Prasankok et al (2009) [26] , and Nantarat et al (2014) [27] , were used ( Fig. 1 , Table 1 ).…”

“…However, shell characteristics can be extremely variable, especially in widely distributed species, due to convergence [14] – [18] or random genetic drift and geographic isolation [19] , [20] . Some studies have investigated the anatomy of Cyclophorus [21] , [22] but it is quite clear that Cyclophorus shows a high degree of anatomical similarity rendering anatomical characters unreliable for use in species discrimination [23] , [24] .…”

“…In Thailand, it was recorded in the western, central, eastern, and northeastern parts of the country. More recently, studies on karyotype [23] , allozyme analysis [26] , and molecular phylogeny [27] have revealed extensive variation within Thai C. fulguratus populations. These genetic variations, in combination with the high degree of intra-specific shell variation in C. fulguratus , would suggest that its classification as a single species warrants reconsideration [23] , [26] .…”

“…More recently, studies on karyotype [23] , allozyme analysis [26] , and molecular phylogeny [27] have revealed extensive variation within Thai C. fulguratus populations. These genetic variations, in combination with the high degree of intra-specific shell variation in C. fulguratus , would suggest that its classification as a single species warrants reconsideration [23] , [26] . The current taxonomic focus on key external shell characteristics, which have been shown in several cases to be strongly influenced by environmental factors, may confound the identification of useful diagnostic characters for the recognition of biological species of Cyclophorus [16] , [26] , [27] .…”

Cytotaxonomy of unionid freshwater mussels (Unionoida, Unionidae) from northeastern Thailand with description of a new species

“…Comparisons with type specimens in the Senckenberg Museum, Frankfurt (SMF) were also conducted. Chromosome preparations were made from gill tissue by the air-drying method, modified from Patterson and Burch (1978), Deein et al (2003) and Kongim et al (2006, 2009, 2010). Living animals recently collected from the wild were treated with colchicine solution for 4 h at a final concentration of 0.01 M. Gill filaments were removed, cut into small pieces, and soaked in 0.075 M KCl for 45 min.…”