Itaquasconinae

Pilato, Giovanni & Binda, Maria Grazia, 2010, Definition of families, subfamilies, genera and subgenera of the Eutardigrada, and keys to their identification, Zootaxa 2404, pp. 1-54 : 49

Key to the genera of the subfamily Itaquasconinae

1. Pharyngeal bulb with only one undivided placoid or no placoids ................................................................................ 2 More than one placoid present*.................................................................................................................................... 4

(*) We do not consider the simplex stadium or pseudosimplex stadium.

2. Caudal tract of the bucco-pharyngeal tube rigid, without spiral thickening ( Fig. 19 A) .................................. Parascon

- Caudal tract of the bucco-pharyngeal tube flexible with a spiral thickening ............................................................... 3

3. Rigid buccal tube longer than the apophyses for the insertion of the stylet muscles; stylet supports present ( Fig. 19 E) ..................................................................................................................................................................... Itaquascon

- Rigid buccal tube very short (as long as the apophyses for the insertion of the stylet muscles); stylet supports absent ( Fig. 19 F) ...................................................................................................................................................... Astatumen

4. Caudal processes of the apophyses for the insertion of the stylet muscles point backwards and sideways ( Fig. 19 B). Branches of the stylet furcae of the Mesocrista type ( Figs. 4 E, 19C) .......................................................... Mesocrista

- Caudal processes of the apophyses for the insertion of the stylet muscles point sideways ( Fig. 19 D). Branches of the stylet furcae of the Platicrista type ( Fig. 4 F)............................................................................................... Platicrista

Figures

FIGURE 4. Stylet furcae shapes. A, typically-shaped furcae (the basal portion is enlarged and has two caudal branches with thickened, swollen, rounded apices); B, Richtersius type (the branches, very robust, have thickened but neither swollen nor rounded apices); C, Insuetifurca type (the branches are arched and converging backwards); D, Eohypsibius type (the branches are arched, without particularly swollen apices); E, Mesocrista type (the basal portion is not very enlarged and the branches have thickened, swollen, rounded apices); F, Platicrista type (the branches are pointing backwards instead of backwards and sideways, and on lateral view they are spoon like and tapering at their apices); G, Astatumen type (the branches are very short and taper at their apices); H, Itaquascon type (the branches are very short and without swollen apices); I, Milnesium type (triangular in shape without long branches pointing backwards and sideways). (A, E, F, G from Pilato, 1987. C, from Guidetti & Pilato, 2003).

FIGURE 19. Bucco-pharyngeal apparatuses of the Itaquasconinae model: A, Parascon type; B, C, Mesocrista type (B, in dorsal view; C, in lateral view); D, Platicrista type; E, Itaquascon type; F, Astatumen type. cp = caudal processes; sts = stylet supports. (A, from Pilato & Binda, 1987 a; B, C, D, from Pilato, 1987; E, from Pilato & Binda, 1987 a; F, from Pilato, 1969 c).