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L amos : Discovery of Belba sculpta M ihel č i č , 1957 169 were illustrated by P érez -Í ñigo (1970, 1997), who comments in the first contribution that they were visible on all specimens of B . aberrans , B . igno­ ta , and B . sculpta which he had examined. They were also evident in all the representatives of the latter which I collected in Mannheim. Two pairs of notogastral light spots clearly homologous to those of Belba sculpta have so far been noted for some species of Metabelba G randjean , 1936 ( H ammen & S trenzke 1953, M ourek et al. 2011), including Metabelba ( Neobelba ) pseudopapilli­ pes B ulanova -Z achvatkina , 1967 ( M iko & K olesni ­ kov 2014). The function of the spots is unclear. It may be that the anterior pair differs functionally from the more posterior one, as they are dissimilar in structure when observed under high magnifica- tion in a light microscope. This is also suggested by the fact that in a few species such as Belba paracorynopus B ulanova -Z achvatkina , 1962 ( M iko et al. 2017) the anterior pair of spots is situated in an identical position on the notogaster relative to the notogastral setae as in B . sculpta , where- as the second pair is instead located posterio- mediad seta lm. It is conceivable that at least the posterior light spots are actually muscle sigillae. A conspicuous oval cuticular sculptured area, with a diameter only slightly less than that of the bothridial opening, is present together with some similar smaller ones anterior and slightly mediad to the bothridium of Belba sculpta . M iko & K olesnikov (2014) interpret an identical structure in Metabelba ( Neobelba ) pseudopapillipes as being an area porosa. I view it as being a small sigillary field instead. Distinct ridges or other linear structures associ- ated with the insertions of the notogastral setae, like they are present in Belba sculpta , have sel- domly been depicted or mentioned in descrip- tions of Damaeidae. Since these are not easy to perceive, I suspect that they are much more common in the family than is suggested by their scarce occurrence in the literature.Three species known for displaying such a ridge system are Da­ maeus onustus K och , 1844 ( A bd - el - hamid 1966), Epidamaeus conjungenus X ie et al., 2011 ( X ie et al. 2011) and Spatiodamaeus conjungenus X ie et al., 2016 ( X ie et al. 2016). B ayartogtokh (2000) notes that in Belba crassisetosa setae c1 and c2 are each situated on a weakly developed longi- tudinal ridge. From a biomechanical perspective it appears that the function of the cuticular ridges is to provide structural support to the notogas- tral setae at their site of insertion and to stabilise the dome-like notogaster against impinging com- pressional and torsional forces. G randjean (1960), in one of the most detailed do- cumentations yet of a damaeid mite, illustrates and describes the notogaster of Damaeus arver­ nensis G randjean , 1960. He does not mention any notogastral ridges associated with setae, but instead comments on two longitudinal notogas- tral grooves. The “grand sillon” ( G randjean 1960, p. 258) of Damaeus arvernensis appears to be homologous to the “line” associated with the no- togastral seta insertions of the Dossenwald Bel­ ba . The second groove mentioned by G randjean (1960), which runs closer to the sagittal plane than the outer groove and is approximately paral- lel to the latter, is indistinct and weakly developed in Belba sculpta . More research is needed before the notogaster of Belba sculpta and other dama- eid mites is fully understood. The ovipositor has been investigated in only a handful of species of Damaeidae such as Damae­ us arvernensis by G randjean (1960), D . riparius N icolet , 1855 by E rmilov (2010b), Belbodamae­ us indicus E rmilov , K aluz & W u , 2013, by E rmilov et al. (2013) and Belba cornuta W ang & N orton , 1995, by E rmilov (2018). The ovipositor of Belba sculpta is similar to the one of these species in possessing two possibly derived traits that are ap- parently absent in all other higher oribatid mites except Hungarobelba B alogh , 1943 ( M iko & T ra ­ vé 1996), although they are known from the Tr- hypochthoniidae within the Macropylina ( E rmilov 2011), namely 1) a short, wide appearance with a broad ovipositor base bDp which is only slightly longer than wide, and very short lobes L1-L3, and 2) an arrangement of the insertions of the setae τ a, τ b, τ c of both eugenital lobes L2 and L3 in the approximate shape of an isosceles triangle. These character states may be synapomorph for the Da- maeidae and Hungarobelbidae. It should be no- ted though, that the ovipositor of Protodamaeus S ubías , 2019, within the Hungarobelbiae M iko & T ravé , 1996, is not described and that virtually no research has been done on the ovipositor of the Ameroidea B ulanova -Z achvatkina , 1957. The presence of a tiny vestigial famulus sun- ken in a sclerotized cup in the nymphs of Belba sculpta is highly unusual, since this trait is so far unknown in published descriptions of species of Belba ( N orton 1979 c , N orton & P alacios -V argas 1982, S eniczak et al. 2013) and similarly not pre- sent in species of possibly related genera such as Caenobelba ( N orton 1980) and Tokukobelba L amos , 2016 ( S eniczak & S eniczak 2013, L amos