A lappet inserted between the appendix interna and the mesial margin of the second pleopod of most male shrimps. The presence or absence of an appendix masculina is the easiest way to distinguish males and females in most caridean shrimps, and in some families, such as the Atyidae, it is greatly enlarged, dwarfing the superimposed appendix interna, and it offers important taxonomic characters. (Pl. appendices masculinae) [Chace and Hobbs, 1969].
A setiferous lobe or rodlike structure situated between the appendix interna and the mesial margin of the mesial ramus (endopod) of the second pleopod of male shrimps. Often an important taxonomic character, the presence or absence of an appendix masculina is the easiest means of distinguishing males and females of most freshwater shrimps [Hobbs, Hobbs, and Daniel 1977].
Accessory male organ located mesially on second pair of pleopods between endopodite and appendix interna [Williams, 1984].
An alternative name for a stylet-like copulatory structure on the male pleopod II. This structure is not homologous to similarly named structures found in non-isopod Eumalacostraca [Wilson, 1989].
Complex median process of 2nd ploepodal endopod of male Caridea and some other Eucarida used in copulation or spermatophore transfer [McLaughlin, 1980].
Complex median process of endopod of second pleopods of male Caridea and some isopods; serves in copulation [Moore and McCormick, 1969].
Flap inserted between appendix interna and inner margin of endopod of the second pleopod in most male shrimps. (Syn. appendices musculinae) [Butler, T.H.].
Lappet, sometimes scalelike, at the mesial base of the endopod of the second pleopod (ventral to the appendix interna if latter present) in some males. (Pl. appendices masculinae) [Perez Farfante and Kensley, 1997].
Lobe or rodlike structure, bearing setae, situated between appendix interna and mesial margin of endoopod of second pleopod of male shrimps. The presence or absence of this structure provides easiest means of distinguishing males from females; an important taxonomic character for palaemonids (see Fig. 73j,k) [Hobbs and Jass, 1988].
Small branch on inner margin of pleopod 2 of males, usually rod-like, proximal to appendix interna. (Pl. appendices masculinae) [Poore, 2004].
(Order Decapoda):
Median process of inner branch (endopod) of second pleopod in male; serves in copulation or spermatophore transfer [Stachowitsch, 1992].
(Order Isopoda):
Copulatory stylet arising from medial margin of male pleopod 2 endopod, used for transfer of spermatophores in at least some species. (Pl. appendices masculinae) [Wetzer et al. 1997].
(Order Isopoda):
Rod-shaped median process on endopod of second pleo-pod in male; serves in sperm transfer. (Syn. male stylet) [Stachowitsch, 1992].
Crustacea glossary. Natural History Museum of Los Angeles County. 2011.