Figure 4

Pleon details of malacostracan representatives. A–D Dikerogammarus haemobaphes (Eichwald, 1841) (Amphipoda). E–H Hyperia sp. (Amphipoda). I–J Fluorescence micrographs of Neosergestes semissis (Burkenroad, 1940) (Dendrobranchiata). K–L Penaeus monodon Fabricius, 1798 (Dendrobranchiata). M–N Euphausia superba Dana, 1850 (Euphausiacea). O–P Thysanopoda tricuspidata Milne-Edwards, 1983. A–D, K–P Photographs of Alizarin-Red stained specimens. E–J fluorescence micrographs. Scale bars A = 1 cm; B–P = 1 mm. Abbreviations as before. A. Pleon from lateral displaying tagmatisation. B. Articulation of plp 3 pointing posteriorly with sc 1– 3. White arrowhead = joint tergopleura–sc 1. C. Articulation of plp 3 pointing anteriorly with scl 1–2, 4–6. White arrowhead as in B. D. Articulation of plp 5 pointing posteriorly. White arrowhead = joint. Note darker area anterior to basipod. E. Pleon of Hyperia sp. from lateral displaying tagmatisation. F. Articulation of plp 3 pointing posteriorly with sc 1–3. Tgpl slightly deformed. White arrowheads = joints of tgpl–sc 1, st–sc 2. Black arrowhead = joints of ba–sc 1. G. Articulation on plp 3 pointing anteriorly with sc 1–2, 4–6. Arrowheads as in F. H. Articulation of plp 5 pointing posteriorly. I. Articulation of plp 3 pointing posteriorly with sc 1 anchored deeply in tergopleura (white arrowhead). J. Articulation of plp 3 pointing anteriorly with sc 1–3. Note uparching sternite on lateral side marked by white star. Black arrowhead = joint ba–sc 1. K. Articulation of plp 3 pointing posteriorly with sc 1, 2. White arrowhead = joint tgpl–sc 1. L. Articulation of plp 3 pointing anteriorly with sc 1–2. Tgpl removed. M. Articulation of plp 3 pointing posteriorly with sc 1–2. White arrowhead = joint st–sc 2. N. Articulation of plp 3 pointing anteriorly with sc 1–3. White arrowhead = joint tgpl–sc 1. Black arrowhead = joint ba–sc 2. O. Articulation of plp 3 pointing posteriorly with sc 1–2. White arrowhead = joint tgpl–sc 1. P. Articulation of plp 3 pointing anteriorly with sc 1–3. White arrowhead as in O.