A new genus of water mites (Acari, Hydrachnidia, Wettinidae) from bromeliad phytotelmata in the Brazilian Atlantic rainforest Author Pesic, Vladimir Author Piccoli, Gustavo Caue de Oliveira Author de Araujo, Marcel Santos Author Rezende, Jose Marcos text ZooKeys 2015 516 27 33 http://dx.doi.org/10.3897/zookeys.516.10179 journal article http://dx.doi.org/10.3897/zookeys.516.10179 1313-2970-516-27 E75454CBFCA7410AB44ACF6E479E139E E75454CBFCA7410AB44ACF6E479E139E Taxon classification Animalia Prostigmata Wettinidae Genus Bromeliacarus Pesic gen. n. Diagnosis. Characters of the family Wettinidae (see Cook et al. 2000 ): dorsum with a large central shield bearing two pairs of glandularia and a pair of postocularia (Fig. 2D), flanked by ring composed of 6 pairs of platelets (Figs 1A, 2A), with 1th, 2nd, 3rd, 4th, and 6th pairs bearing glandularia; 6th pair of platelet fused to each other, occasionally on one side 5th platelet fused with 4th platelet. Venter with coxal plates and genital field fused into a ventral shield (Figs 1B, 2C, 2E); suture lines indicating posterior edges of anterior three coxal plates weakly indicated but directed posteriorly; IV-L insertion laterally, well separated from each other and without projections; coxoglandularia 1 in posterior edges of Cx-II; Cx-IV without glandularia; coxoglandularia 2 between Cx-IV and genital field. Legs: I-L stocky, I-L-6 with a long and deep claw socket extending over more than half the dorsal segment surface (Fig. 1E), claw large, ventral clawlet apically rounded, slightly longer than main claw (Fig. 1C); legs I-IV without swimming setae. Genital field with 7-9 pairs of acetabula; acetabular plates fused with ventral shield in both sexes (Figs 1B, 2C); suture lines between genital field and ventral shield obliterated; excretory pore incorporated into ventral shield. Gnathosoma with relatively long apodemes (Fig. 1K); palp slender, P-4 bearing two short ventral setae inserting in the centre and a peg-like mediodistal seta (Fig. 1 F-G ). Figure 1. A-H Bromeliacarus cardoso sp. n., female: A idiosoma, dorsal view B idiosoma, ventral view C claw of first leg D I-L E I-L-5 and -6 F palp, lateral view G palp, medial view H chelicera I IV-L K gnathosoma. Scale bars: 100 µm . Figure 2. A-E Bromeliacarus cardoso sp. n. (A, D-E female B-C male) A-C line drawing D-E photographs: A ring of platelets surrounding dorsal plate B gnathosoma C, E idiosoma, ventral view D dorsal plate. Scale bars: 100 µm . Type species. Bromeliacarus cardoso sp. n. Etymology. Named for its occurrence in bromeliad phytotelmata, and the Latin acarus meaning "mite" . Remarks. Adults of Bromeliacarus gen. n. share with those of all Wettinidae the apomorphic characteristic modifications of first leg (short and stocky with tarsal claw sockets exceptionally large and claws large with ventral clawlet slightly longer than main claw) and fourth leg (trochanter being long and massive, tarsal claw sockets reduced) and the posterior orientation of the suture lines between coxal plates. This new species is autapomorphic in having 7-9 pairs of genital acetabula flanking the gonopore. Other members of Wettinidae differ in exhibiting the plesiotypic character state of small number of genital acetabula (i.e., Stormaxonella K.O. Viets, 1962 with four pairs of acetabula, all other genera with three pairs of acetabula but one species of Wettina ( Wettina octopora Cook) with four pairs. Due to the similar structure of dorsal shield, the new genus appears to be related to Stormaxonella K.O. Viets, 1962. This character state is apomorphic and may indicate that both genera belong to a monophyletic group within Wettinidae . However in light of striking difference in genital field and palp ( Stomoxanella scutulata is autapomorphic in P-4 bearing one thick, spatulate seta medially in proximal third of segment) it would appear that divergence from a common ancestor have occurred early during wettinid evolution. Cook et al. (2000 ; 437) claim that "the occurence of different clades on widely separated land masses in both the Northern and Southern Hemispheres suggests that members of this family were distributed throughout Pangea before it broke apart during the Jurassic".