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 1^th, 2^nd, 3^rd, 4^th, and 6^th pairs bearing glandularia; 6^th pair of platelet fused to each other, occasionally on one side 5^th platelet fused with 4^th 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. 1F–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.

Bromeliacarus cardoso sp. n.

Named for its occurrence in bromeliad phytotelmata, and the Latin acarus meaning “mite”.

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 (W. 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”.

Holotype female, dissected and slide mounted in Hoyer’s fluid, Brazil, São Paulo, Cananéia, 25°04'16"S, 47°55'23"W, in Quesnelia arvensis (Vellozo) Mez. (Bromeliaceae), v.2013 col. Gustavo Cauê de Oliveira Piccoli. Paratype: three females (two of them damaged, palps and legs lacking), one male (damaged, palps and legs lacking), same data as holotype, two females (both damaged) and one male dissected and slide mounted in Hoyer’s fluid.

As given for genus.

Character states as given in generic diagnosis.

Female (holotype, in parentheses some measurements of paratype): Idiosoma (ventral view: Fig. 1B) L/W 434/375 (441-456/367-400). Dorsal shield (Figs 1A, 2D) L/W 363/308 (398-409/309-322), ratio 1.18 (1.27–1.29); gnathosomal bay L 69 (78); distance between IV-leg insertions 172 (173); gonopore L/W 69/39 (63/40), distance between most lateral pairs of Ac 146 (151). Palp (Figs 1F-G): total L 177; L/H, L/H ratio: P-1, 25/14, 1.8; P-2, 44/28, 1.6; P-3, 32/20, 1.6; P-4, 48/15, 3.1; P-5, 28/8, 3.4; gnathosoma vL 72, with apodemes 105; chelicera total L 86. Legs: dL of I-L (Fig. 1D): 41, 51, 40, 52, 51, 74; I-L-6 H 26, I-L-6 dL/H ratio 2.8; dL of II-L-2-6: 59, 44, 55, 64, 72; dL of III-L-2-6: 56, 45, 59, 72, 72; dL of IV-L (Fig. 1I): 75, 56, 66, 69, 71, 74.

Male: Idiosoma (ventral view: Fig. 1C) L/W 434/375. Dorsal shield L/W 384/306, ratio 1.26; gnathosomal bay L 77; distance between IV-leg insertions 167; gonopore L/W 54/6, distance between most lateral pairs of Ac 148.

Named after the locality (State Park of Ilha do Cardoso, São Paulo, Brazil) where the new species was detected.

The number of acetabula flanking the gonopore varies from 7 to 9 on each side. We found three different combinations Ac numbers flanking (right+left) the gonopore: 7+9 (one male), 8+8 (one female) and 8+9 (two females).

Brazil; only known from the type locality.

Members of Bromeliacarus cardoso sp. n., are unusual about their habitats, because they appear to live only in the water-filled leaf axils of the bromeliads, where they walk attached to submerged detritus in bromeliads tank or free swimming in water column. Additional collecting effort is clearly needed in order to understand life history as well as habitat preferences of this species. However, as already mentioned by Albertoni and Fikáček (2014), the usual method used for searching for fauna inside bromeliads, i.e. dismantling the leaves one by one and washing the content in a tray, may not to be effective enough for very small species.