Carolinea 74

L amos : Tokukobelba gen. nov. (Acari: Oribatida: Damaeidae) 89 3-3 shown by Tokukobelba reflects the anches- tral character state for the family instead. Epimeral apophyses In Tokukobelba the epimeral setae, particularly those of epimeres III and IV, insert on or directly adjacent to greatly enlarged tubercles or apo- physes (Figs 2, 3) except apparently in T itsuk­ iensis ( F ujikawa 2008). Although epimeral setae are sited on tubercles in several damaeid spe- cies including Dyobelba carolinensis ( N orton 1979c), D . paucituberculata ( B ayartogtokh et al. 2001) and Epidamaeus gilyarovi ( B ehan - P elle - tier & N orton 1985), these are generally small, relatively inconspicuous and not associated with setae 4a, 4b, 4c. The only other Damaeidae besides Tokukobelba in which all epimeral se- tae insert on enlarged tubercles are Dyobelba crossleyi , D . dindali , D . granulata and D . tectope­ diosa based on B ayartogtokh & N orton (2007). However, in these as in all Damaeidae besides Tokukobelba , epimeral grooves III and IV and their apodemes are inconspicuous. Furthermore, in Tokukobelba the tubercles as- sociated with setae 3a, 3c, 4a, 4b and espe- cially 4c are massive, relatively very much larger than in any other damaeid mite. In Costeremus yezoensis and C . barbatus , all of the epimeral setae insert on sizeable tubercles ( F ujikawa & F ujita 1985, C hoi 1997a). The tubercles of Hun­ garobelba ( M iko & T ravé 1996) are somewhat smaller than those of Tokukobelba . In other Am- eroidea such tubercles are generally absent, and they only rarely occur within the Brachypylina ( W oas 2002). The enlarged epimeral apophyses of Tokukobelba associated with the epimeral se- tae appear to be a derived feature of the genus and is suggestive of affinities to Dyobelba and possibly to some species of Costeremus . Complete enantiophyses E2 and V are found in Tokukobelba compta . Apophyses E2p and Vp are monotuberculate. The posterior borders of epimeres I and II of T compta are exceptional, very different from all other Damaeidae, where typically either one or both of the apophyses E2a and Va are present and monotuberculate or both are absent, and the region shows no apophyses. In T compta there is a row of closely spaced sizeable tubercles or a tuberculate ridge at the posterior margins of epimeres I and II (Figs 2, 3). Apophyses E2a and Va are conspicuously mul- tituberculate. A complete ventrosejugal enan- tiophysis with Va multituberculate also occurs in Tokukobelba mongolica ( B ayartogtokh 2000), T. barbata ( F ujita & F ujikawa 1986) and T japoni­ ca ( A oki 1984). The latter two contributions also depict a multituberculate apophysis E2a. Enan- tiophyses E2 and V are only known to be absent in T itsukiensis ( F ujikawa 2011). The tubercles comprising the epimeral ridges in Tokukobelba are frequently fused at the base, and the ridges are elongate, with the one of epimere II in T compta , for example, oppos- ing a region on epimere III ranging from a point situated well mediad apophysis Vp to the lateral margin of the posterior parastigmatic apophysis Sp, when observed in ventral perspective. One of the large tubercles of the epimeral ridge, the one with the greatest lateral extension, appears to correspond to the anterior parastigmatic apo- physis Sa. A posterior epimeral margin II with a tuberculate ridge, reminiscent of Tokukobelba is found in some Eremaeidae such as Eremaeus gracilis B ehan - P elletier , 1993, E . nortoni B ehan - P elletier , 1993, and Eueremaeus nemoralis B ehan - P elletier , 1993, based on their excellent descriptions and illustrations in B ehan - P elletier (1993) and also in Costeremus yezoensis , based on the depiction in F ujikawa & F ujita (1985, Fig. 1c), being otherwise highly uncommon within the Brachypylina. The homology of the tuberculate posterior ridges of epimeres I and II with apophyses E2a, Va and Sa respectively, is probable, but not absolutely certain. The possibility exists that they are, for ex- ample, enlarged microtubercles and/or that the genetic factor resulting in the general verrucose ornamentation of the epimeres is simply act- ing more strongly in the posteriormost region of epimeres I and II. In the tritonymph of T compta , enlarged tubercles representing the future apo- physes E2p and especially Vp are distinct, but there is no trace of tuberculate structures on the posterior borders of epimeres I and II. Enantiophyses E3 and E4 have up to now been assumed to be absent in the Damaeidae, al- though N orto n & B ehan - P elletier (2009, p. 498, Fig. 15.6 F) illustrate an exemplary damaeid mite based on Damaeus arvernensis G randjean , 1960, with a pronounced epimeral enantiophysis IV. In Tobukobelba compta , T verrucosa ( B ulano - va - Z achvatkina 1962) and T barbata ( F ujita & F u - jikawa 1986), the tubercles associated with seta 4a are of the same size as apophysis Vp (Figs 2, 3), with the ratio of their surface area relative to body length considerably exceeding that of any other damaeid mite. Their size and position strongly suggest that they represent apophyses