Gamasellodes intermedius, Rueda-Ramírez, Diana, Varela, Amanda & De Moraes, Gilberto J., 2016

Rueda-Ramírez, Diana, Varela, Amanda & De Moraes, Gilberto J., 2016, Soil mites of the families Ascidae, Blattisociidae and Melicharidae (Acari: Mesostigmata) from mountainous areas of Colombia, Zootaxa 4127 (3), pp. 493-514 : 498-500

Gamasellodes intermedius sp. nov.

( Figs 7–12 )

Specimens examined. Holotype female and five paratype females from soil of a grassland ( pH 5.5–6.1; organic matter 28–36%; humidity 71–75%; soil temperature 10–16°C); collected by D. Rueda-Ramirez in April and June, 2010. Holotype and two paratype females deposited at ESALQ-USP; two paratype females deposited at MJHN- PUJ.

Diagnosis. Anterior region of epistome with three subequal projections of uniform width, each bifurcate; podonotal shield with sparse and light reticulation behind j 4, smooth anteriorly, with a well define slender strip between z 3 and s 4, and with 17 pairs of setae (s 2 on unsclerotised cuticle); j 1, j 2 and z 1 almost in transverse line; opisthonotal shield mostly smooth, and with 16 pairs of setae (R 5 inserted on posterior angle of dorsal shield); with two pairs of rounded to ovoid metapodal plates; ventrianal shield with four pairs of setae in additional to circumanal setae (Jv 1, Zv 1 and Zv 2 on unsclerotised cuticle); peritreme short, extending anteriorly only to level of anterior margin of coxa IV (level of r 5); peritrematic plate extending anteriorly to level between z 1 and s 1, not fused to dorsal shield.

Description (Female, six specimens measured).

Gnathosoma. Fixed cheliceral digit 26 (25–27) long, with five teeth and setiform pilus dentilis; movable digit 26 (25–27) long, with two teeth; dorsal and antiaxial lyrifissures and dorsal cheliceral seta distinct ( Fig. 7 ). Numbers of setae on palp trochanter–tarsus: 2, 5, 6, 14, 15; palp tarsal apotele bifurcate. Anterior region of epistome with three subequal projections of uniform width and each bifurcate ( Fig. 8 ). Deutosternal groove ( Fig. 9 ) delimited laterally by subparallel lines, with seven transverse lines, of which the most distal smooth and others with 9–15 denticles each. Internal malae distinctly separate from each other; lateral margins fimbriate. Corniculi hornshaped, about 1.6 times as long as their basal width. Seta h3 about in longitudinal line with h 1 and mesad of and in transverse line with h 2. Setal measurements: h 1 12 (11–13), h 2 9 (8–10), h 3 15 (13–17), pc 14 (13–15), palp trochanter av 17 (16–17), palp trochanter pv 11 (10–11); setae aciculate and smooth.

Dorsal idiosoma ( Fig. 10 ). Idiosoma 240 (231–248) long and 112 (107–124) wide at widest level. Podonotal shield with sparse and light reticulation behind j 4, smooth anteriorly, with well define slender strip between z 3 and s 4; 123 (117–129) long and 110 (107–115) wide at widest level; with 17 pairs of setae, two pairs of distinguishable lyrifissures and two pairs of pores; j 1, j 2 and z 1 almost in transverse line. Unsclerotised cuticle laterad of podonotal shield with five pairs of setae (s 2, r 2 –r 5). Opisthonotal shield mostly smooth, with a line immediately behind J 1 extending diagonally to anterolateral corners, with scant lines by Z 1, a wavy line between J 3 and Z 3, and with a shallow ovoid depression between J 4 and J 5, more clearly discernable near posterior margin; 117 (114–119) long and 108 (105–110) wide; with 16 pairs of setae (R 5 inserted on posterior angle of dorsal shield), six pairs of distinguishable lyrifissures and two pairs of pores. Setae J 4 shorter than distance between their bases (24–26). Unsclerotised cuticle laterad of opisthonotal shield with four pairs of setae (R 1– R 4) and a pair of lyrifissures ( Rp). Setal measurements: j 1 11 (10–12), j 2 14 (11–16), j 3 18 (17–20), j 4 19 (17–20), j 5 16 (15–17), j 6 16 (15–17), J 1 16 (15–17), J 2 18 (16–19), J 3 18 (16–19), J 4 22 (20–24), J 5 13 (12–15), z 1 9 (9–10), z 2 17 (15–18), z 3 19 (17–20), z 4 21 (19–23), z 5 21 (20–22), z 6 20 (18–21), Z 1 21 (20–23), Z 2 21 (19–22), Z 3 22 (20–23), Z 4 22 (20–24), Z 5 22 (21– 24), s 1 15, s 2 12 (10–13), s 3 20 (18–23), s 4 22 (18–23), s 5 21 (20–23), s 6 20 (19–22), S 1 18 (16–20), S 2 19 (17– 20), S 3 21 (20–22), S 4 21 (20–22), S 5 20 (19–22), r 2 14 (13–15), r 3 25 (24–25), r 4 11 (10–12), r 5 11 (10–12), R 1 10 (9–10), R 2 10 (10–11), R 3 12 (11–12), R 4 13 (12–13), R 5 14 (13–15); setae aciculate and smooth.

Ventral idiosoma ( Fig. 11 ). Base of tritosternum 16 (15–16) long and 10 (9–10) wide proximally; laciniae 45 (44–46), separated for about 90% of their total length, pilose. Pre-sternal area weakly sclerotised, with light punctation distinguishable in some specimens. Sternal shield, mostly smooth, with scant faint marginal striae; posterior margin lightly sclerotised and lightly concave; approximately 65 (58–71) long and 54 (50–56) wide at widest level; with three pairs of setae and three pairs of lyrifissures (iv 3 hardly distinguishable); distances st 1 –st 3 55 (55–57), st 2 –st 2 35 (34–35). Metasternal plates indistinguishable; however, fourth pair of sternal setae (st 4) on unstriate, lightly sclerotised region. Genital shield narrow, mostly smooth, punctate along convex posterior margin, bearing st 5 and extending posteriorly well behind coxa IV; 59 (56–61) long and 25 (24–26) wide at the widest level; distance st 5 –st 5 24 (23–25); lyrifissure iv 5 on unsclerotised cuticle posterolaterad of st 5. Two pairs of ovoid to rounded metapodal plates. Ventrianal shield reticulate; 66 (65–67) long and 92 (87–95) wide at widest level; with four pairs of setae (Jv 2– Jv 5) in addition to circumanal setae; para-anal setae inserted at about mid-length of anal opening; the latter small, about 1/5 of shield length; 14 (13–15) long. Unsclerotised cuticle between genital and ventrianal shields three pairs of setae (Jv 1, Zv 1 and Zv 2), a pair of tiny transversely elongate platelets and a pair of lyrifissures. Unsclerotised cuticle laterad of and posteriorad to ventrianal shield with two pairs and a pair of lyrifissures, respectively. Anterior section of endopodal plate fused with sternal shield; section behind sternal shield indistinct. Exopodal plate reduced to triangular platelets between coxae II–III and III–IV and an elongate plate next to coxa II. Peritreme short, extending anteriorly only to level of anterior margin of coxa IV (level of r 5). Peritrematic plate abutting but not fused to dorsal shield at level of z 1 and s 1 and ending as a blunt and slightly curved extension at level of posterior margin of coxa IV; with a lyrifissure next to s 2 (median level of coxa II), a lyrifissure next to r 4 (median level of coxa III), and a lyrifissure and a pore posterior to stigma. Setal measurements: st 1 13 (11–14), st 2 12 (11–13), st 3 13 (11–13), st 4 12 (10–13), st 5 10 (10–11), Jv 1 14 (11–15), Jv 2 16 (15–17), Jv 3 17 (16–18), Jv 4 15 (13–17), Jv 5 23 (22–24), Zv 1 12 (11–13), Zv 2 13 (11–14), para-anal 23 (20– 24), post-anal 23 (22–24); setae aciculate and smooth.

Spermathecal apparatus. Not distinguishable.

Legs. Lengths: I: 211 (205–215); II: 150 (140–158); III: 139 (130–145); IV: 180 (170–189). Setation (legs I– IV): coxae: 2, 2, 2, 1; trochanters: 6, 5, 5, 5; femora: 12, 11, 6, 6; genua: 13, 11, 8, 9; tibiae: 13, 10, 8, 9; tarsi: not counted, 18, 18, 18. All legs with pretarsi containing a pair of strongly sclerotised claws ( Fig. 12 ); median section of pulvilli of legs I–IV rounded.

Adult male. Not found.

Etymology. The specific name “ intermedius ” refers to fact that the morphological characteristics of this species are intermediate between Protogamasellus and Gamasellodes .

Remarks. This species is most similar to Gamasellodes minor Athias-Henriot, 1961 , described from Algeria, with similar ornamentation on the posterior part of the opisthonotal shield, setae J 4 shorter than the distance between their bases (respectively 18 and 23 in G. minor ), and with short peritreme. However, the latter species differs from the species here described by having a continuous line connecting the bases of j 4 and z 3 and by having one less pair of opisthogastric setae (Zv 2). In addition, the opisthonotal shield of G. minor has only 15 pairs (R 5 inserted off dorsal shield). Although placed in Gamasellodes , the generic classification of this species is doubtful, because some characteristics are typical of Protogamasellus , namely the transverse line at level of setae J 1, while other characteristics are typical of Gamasellodes , namely the absence of a transverse line extending completely across the level of z 6, the presence of nine setae on genu IV and the anterior region of epistome most often with three pointed or distally denticulate projections. Some species of Gamasellodes have short peritreme ( Moraes et al., 2016); however, except for G. minor , the peritreme extends at least to level of posterior half of coxa II.

Figures

FIGURES 7 – 12. Gamasellodes intermedius sp. nov. Female. 7. Chelicera; 8. Epistome; 9. Hypostome and proximal palp segments; 10. Dorsal view; 11. Ventral view; 12. Tarsus II.