Fig. 4

LM images showing the transverse (a-c) and coronal (d-f) sections of a gill filament of L. fortunei. Filaments stained with hematoxylin and eosin are shown in the images (a, e). The filaments stained with Alcian Blue/PAS shown in images (c, d, f), and stained with Masson’s trichrome in image (b). Neutral mucopolysaccharides (NMPS) are coloured in pink and acid mucopolysaccharides (AMPS) are coloured in blue. Lateral cilia [lc], laterofrontal cirri [lfc], frontal cilia [fc], marginal food groove [mfg], and collagenous structure [cs] are indicated