Figure 15 in The morphological and functional variability of pleon-holding mechanisms in selected Eubrachyura (Crustacea: Decapoda)

Figure 15. Pleon-holding mechanism of Pseudothelphusidae. a-b: Hypolobocera chilensis (Lucas in H. Milne Edwards & Lucas, 1844), ♂, 70 × 41 mm, Dominica (ZRC1998.5). (a) Thoracic sternum without pleon, small button visible. (b) Ventral surface of pleon, hook-like socket visible. c-e: Neopseudothelphusa fossor (Rathbun, 1898), ♂, 23 × 15 (ZMK1688), 3D volume and surface recronstruction from µCT images, holding mechanism not engaged. (c) Three-quarter view of complete specimen. Pleon not firmly attached, right button visible. (d) Same specimen, telson and pleon segment 6 removed. Both buttons visible inside sterno-abdominal cavity. (e) Specimen in frontal view, shift of non-fastened pleon indicated by arrow, right button visible. A: anterior; B: button; G: gonopods; i: intestine; P: posterior; s: setae; sac: sterno-abdominal cavity; so: socket; S5: sternite 5; t: telson. Orange: telson; red: buttons; yellow: pleon segments. Scale bar = 5 mm.