Fortuynia churaumi Pfingstl, Shimano & Hiruta, 2019

Pfingstl, Tobias, Hiruta, Shimpei F., Hagino, Wataru & Shimano, Satoshi, 2021, Juvenile morphology of seven intertidal mite species (Acari, Oribatida, Ameronothroidea) from the East Asian region, International Journal of Acarology 47 (6), pp. 536-554 : 540-541

Fortuynia churaumi Pfingstl, Shimano & Hiruta, 2019

Larva and protonymph unknown.

Deutonymph

(N = 1): length 350 µm.

Prodorsum. Interlamellar seta and exobothridial setae minute.

Gastronotic region. Fifteen pairs of normal spiniform notogastral setae; c 1-3, da, dm, dp, la, lm, lp, h 1-3, p 1-3. All setae approx. same length (19–22 µm), except for h 2 considerably longer (31 µm).

Podosoma and venter ( Figure 7 (a)). Epimeral setation 3-1-2-2, seta 4b added in this stage. Two pairs of short genital setae g 1-2 (13–16 µm). One pair of aggenital setae. Three pairs of adanal setae flanking anal orifice. Two pairs of vestigial anal setae.

Legs. Setation and solenidia are shown in Table 2.

Tritonymph

(N = 16): length 388–419 (mean 396 µm).

Gastronotic region ( Figure 8 (a,c)). Fifteen pairs of notogastral setae (25–62 µm), no difference from deutonymph.

Podosoma and venter ( Figure 8 (b)). Epimeral setation 3-1-3-2, seta 3 c close to trochanter III. Four pairs of genital setae g 1-4. One pair of aggenital setae.Three pairs of adanal setae, ad 1 longest (ca.28 µm). Two pairs of anal setae fully developed.

Legs ( Figure 9 ). Femora I and II with large elliptic porous areas on paraxial side. Two slender paraxial longitudinal porous areas on femur III, one dorsally the other ventrally. Elliptic or kidney-shaped porous areas on paraxial dorsal side of trochanter III–IV. Setation and solenidia shown in Table 2.

Remarks

Fortuynia churaumi adults show a specific reticulate pattern (fine dense granulation interrupted by non-granular lines) on their femora (see Pfingstl et al. 2019b, Figure 3 ), this pattern is already observable in the tritonymph.

Fortuynia shibai and F. churaumi may occur syntopically in some locations on the Japanese islands ( Pfingstl et al. 2019b). Adults can be easily distinguished and the same applies to juveniles allowing to easily separate them if contained in a single sample. Fortuynia shibai immatures always show distally barbed notogastral setae (vs. smooth in F. churaumi ) and these setae are considerably longer than in F. churaumi .

Figures

Figure 3. Fortuynia shibai protonymph. (a) dorsal view. (b) ventral view (distal legs segments and gnathosoma omitted). (c) lateral view (seta h1 covered by seta h2 and therefore not indicated; legs drawn without setation).

Figure 7. Japanese Fortuynia juveniles.(a) F. churaumi, deutonymph ventral view.(b) F.rotunda, larva dorsal view (slightly laterally rotated).(c) F. rotunda, protonymph ventral view (distal leg segments and gnathosoma omitted). (d) F. rotunda, tritonymph dorsal view.

Figure 8. Fortuynia churaumi tritonymph.(a) Dorsal view.(b) ventral view (distal leg segments and gnathosoma omitted). (c) lateral view (legs drawn without setation).

Figure 9. Fortuynia churaumi tritonymph, left legs antiaxial view. (a) Leg I. (b) Leg II. (c) Leg III. (d) Leg IV.