Laser scanning confocal micrographs of the anterior region and haptor of Omanicotyle heterospina n. gen. et n. comb. a, Muscular elements of the anterior region stained with Alexa Fluor® 594 phalloidin. The septum of each buccal sucker (bs) is clearly evident. The lower edge of each sucker appears to be serrated or crenulated by contraction of the fine muscles in this region but are not spine bearing. The buccal cavity leads to a muscular circular pharynx (p), a short oesophagus (o) and an unarmed genital atrium (ga). b, oblique view of the symmetrical haptor which bears up to 50 pairs of clamps arranged in two equal rows. The vitellaria and pigment granules are visible as two parallel, dark, patterned bands running the length of the haptor. c, dual staining of the attachment clamps with phalloidin and the chromotrope 2R-based stain to reveal the main sclerotised component and the associated musculature. d, anterior, forward projecting section of the haptor stained with 40 mM chromotrope 2R (C2R) + 3 mM phosphotungstic acid + 0.5% acetic acid for 4 h at room temperature. The photograph shows that clamps develop in a posterior to anterior direction and the lateral margins of this region of the haptor bear numerous C2R positive droplets (dr). Scale bars: a = 44.34 μm; b = 112.94 μm; c = 20.58 μm; d = 44.27 μm.