Arrhopalites ezoensis, Zeppelini, 2004

Zeppelini, Douglas, 2004, The genus Arrhopalites (Collembola, Arrhopalitidae) in Asia, with the description of two new Japanese species of Yosiis collection, Zootaxa 430 (1), pp. 1-26 : 4-5

Arrhopalites ezoensis sp. n. ( Fig. 3 , A­J)

Etymology. Unknown, this name was suggested by Dr. R. Yosii in the slide of the type material.

Type Material. Holotype female ♀, JAPAN, Hokkaido, Nukabiravi Hidaka. 29­vii­ 1971. R. Yosii, Muséum dhistoire naturelle, Ville de Genève . Paratype female ♀ in the same slide with the Holotype.

Description. Pygmaeus­group s. str. Body sparsely clothed with short setae on anterior part of abdomen (Fig. C, a). Posterior part of the abdomen with setae 1.5 X as long anterior anterior setae (Fig. C, b). Antennae of holotype ~ cephalic diagonal. Ant. IV ~ 2X as long as Ant. III, not subdivided (Fig. A); longest setae 0.75X the width of segment; Ant. IV apex with a capitate sense rod (Fig. A). Ant. III swollen basally; sense organ (Fig. B) with 2 parallel sense rods in a single shallow pit; seta Aai club­shaped and blunt; seta Api short and acuminate, Ape slender and acuminate; Ae, Ap and Ai normal elongate setae. 1+1 eyes. A3, M4 and L and IL series spinelike, M5 absent (Fig. I). Metatrochanteral organ (seta D2) elongate (Fig. F). All ungues with inner tooth and no tunica (figs. J, a­c). All unguiculi with corner tooth, first unguiculus with apical filament reaching the unguis tip (Fig. J, a). Corpus tenaculum with one seta (Fig. G). Dens with 5 dorsal E setae, E1­4 spinelike, E5 normal; L1 and L2 spinelike, L4 absent; D1, D2, Id1, Id2, Id3 and Id4 present (Fig. D); 4 ventral rows of setae (3,2,1,1) present (Fig. D). Mucro narrow, gutterlike, both edges serrate (Fig. E). No cuticular spines on anal valve; C series normal, chaetotaxy (Fig. H). Female subanal appendage thick, straight with serrate apex. Total length of the adult female holotype 0.9mm.

Distribution. Biogeographic zone 3a.

Remarks: Arrhopalites ezoensis n. sp. is a Japanese surface species of the pygmaeusgroup s. str. ( Bretfeld, 1999) similar to A. diversus Mills 1934 , A. slovacicus Nosek 1975 and A. styriacus Nosek & Neuherz 1976 . The feature that holds those species together is the presence of a single seta on the corpus tenaculum. A. ezoensis n. sp. differs from the others in having the undivided fourth antennal segment and corner tooth on all unguiculi; also in the anal valve chaetotaxy, the absence of D5, D10 and E8 setae as well as the female subanal appendage.

Figures

FIGURE 3. A. ezoensis sp. n. A, fourth antennal segment; B, apical sensory organ of third antennal segment; C, body setae (a, anterior, b, posterior); D, ventral and dorsal chaetotaxy of the dens; E, mucro; F, metatrochanteral organ; G, tenaculum; H, anal valve chaetotaxy; I, posterior cephalic chaetotaxy; J, foot complex (a, first leg, b, second leg, c, third leg).