Primary papillae Talk about structure and make a diagram showing differences between
Peripatidae and
Peripatopsidae primary papillae • when found on distal part of foot known as distal papillae • when found on basal part of foot known as basal papillae • scale ranks are responsible for velvety feel
Type 1 sensilla Type 1 sensilla are a specialized variant of primary papilla with a prominent apical piece covered in scales and a sensory bristle with a textured base. These papillae act as
mechanoreceptors, giving the animals a sense of
touch, and occur in
peripatid velvet worms.
Type 2 sensilla Type 1 sensilla are similar to type 1 sensilla but lack an apical piece and have a far longer bristle.
Spindle-shaped sensilla Spindle-shaped sensilla are a modified version of Type 1 sensilla that have a large, spindle-shaped apical piece and a short, thorn-like bristle. Like regular type 1 sensilla, these also only occur in
peripatid velvet worms. In life, spindle-shaped sensilla make up an array known as the antennal sensory field. This is located on the underside of the
antennae on its
proximal (closer to the base) portion.
Accessory papillae Crater shaped papillae • crater shaped papillae in
Neopatida have a rudimentary apical piece, while those in basal Asian clade do not == Pigmentation ==