Blattisocius keegani Fox

Britto, Erika P. J., Lopes, Paula C. & De, Gilberto J., 2012, Blattisocius (Acari, Blattisociidae) species from Brazil, with description of a new species, redescription of Blattisocius keegani and a key for the separation of the world species of the genus, Zootaxa 3479, pp. 33-51 : 43-47

Blattisocius keegani Fox

Blattiosocius [sic] keegani Fox, 1947: 599 .

Blattisocius keegani .— Haines, 1978: 21; Treat, 1975: 94. Melichares (Blattisocius) keegani .— Evans, 1958: 209. Melichares keegani .— Hirschmann, 1962: 30.

Diagnosis. Adult females: dorsal shield reticulate, with 33 pairs of setae (including s2). With eleven pairs of marginal (r–R) and six pairs of submarginal (UR) setae on unsclerotised cuticle. Sternal shield with sinuous longitudinal striae, with posterior margin truncate. Genital shield with longitudinal striae, truncate. With two pairs of metapodal plates. Ventrianal shield reticulated, approximately pentagonal and with three pairs of opisthogastric setae. Peritreme short, reaching only median level of coxa III. Fixed cheliceral digit much shorter than movable cheliceral digit, with three teeth in addition to apical tooth and setiform pilus dentilis; movable digit with one tooth in addition to apical tooth. Spermathecal calyx horn-like, variously constrict near vesicle; atrium globular. Adult males: ornamentation of dorsal shield, number of dorsal shield setae, insertion of s2, shape and relative lengths of dorsal shield setae, marginal and submarginal setae as in adult females. Sternogenital shield with scanty striae, with an indentation behind st4. Ventrianal shield approximately hemispherical, reticulate. Fixed cheliceral digit with two or three teeth in addition to apical tooth and setiform pilus dentilis; movable digit with one tooth in addition to apical tooth; spermatodactyl distally curved, with a membrane along dorsal surface, subterminal ventral spine–like projection and concave apex.

Adult females ( Fig. 5 A–G) (five specimens examined).

Dorsum of idiossoma ( Fig. 5 A): dorsal shield reticulate, 445 (420–470) long and 202 (193–210) wide at level of s4. Podonotal region of dorsal shield with 18 pairs of setae: j1 17 (16–18), j2 33 (30–35), j3 41 (40–43), j4 40 (38–42), j5 40 (36–42), j6 42 (40–43), z1 18 (16–20), z2 39 (35–43), z3 42 (40–45), z4 46 (44–48), z5 40 (38–42), z6 44 (43–45), s1 29 (27–30), s2 36 (35–38), s3 42 (40–46), s4 48 (45–50), s5 47 (45–48), s6 45 (43–47); with five pairs of lyrifissures and four pairs of pores. Opisthonotal region with 15 pairs of setae: J1 44 (42–48), J2 46 (43– 50), J3 39 (37–40), J4 38 (36–40), J5 24 (22–25), Z1 47 (45–50), Z2 46 (44–47), Z3 42 (39–43), Z4 42 (40–43), Z5 45 (44 – 45), S1 44 (41–45), S2 42 (40–45), S3 42 (40–45), S4 45 (44–48), S5 35 (32–36); with nine pairs of lyrifissures and two pairs of pores. Unsclerotised cuticle along dorsal shield with 12 pairs of marginal setae [r2 34 (32–38), r3 38 (35–40), r4 39 (36–43), r5 41 (37–45), r6 40 (37–44), R1 37 (35–40), R2 33 (30–35), R3 34 (30– 35), R4 34 (32–36), R5 33 (30–36), R6 33 (30–35), six pairs of submarginal setae [UR1 33 (30–36), UR2 33 (30– 36), UR3 30, UR4 29 (25–32), UR5 30 (27–32), UR6 31 (28–35)] and two pairs of lyrifissures. Dorsal shield setae of moderate lengths, nearly as long as distance between their bases and bases of corresponding subsequent setae, except j1, J5 and z1, slightly shorter than others; setae smooth, except J3–J5 and Z5, serrated.

Venter of idiosoma ( Fig. 5 B): all setae setiform; base of tritosternum 10 long and 15 (13–15) wide; laciniae free for approximately 45% of their total length of 72 (60–75). Sternal shield 87 (85–90) long and 71 (70–75) wide at level of st2, with sinuous longitudinal striae and narrow projections between coxae I–II bearing a pore at the end. Metasternal shield absent; st4 and associated lyrifissure (iv3) on unsclerotised cuticle. Genital shield longitudinally striate, 171 (168–175) long (including membranous anterior region) and 88 (83–91) wide near posterior margin; posteriorly truncate; genital seta 27 (25–28); paragenital lyrifissures on unsclerotised cuticle, posterolaterally to genital setae. With a very narrow plate between genital and ventrianal shields. With two pairs of metapodal plates, the posterolateral of which longer. Ventrianal shield reticulate, approximately pentagonal, slightly concave near Jv2, 136 (128–150) long and 97 (90–105) of greater width; with a punctate area (cribrum) behind anal opening; with three pairs of opisthogastric setae [JV1 28 (26 –30), JV2 36 (32–40), JV3 43 (42–47)], a pair of lyrifissures on the anterior margin, laterad of JV1, and a pair of pores on lateral margin, approximately in level with posterior margin of anal opening; para–anal seta about as long as the post–anal seta, 23 (22–25) and 25 (23–26), respectively. Unsclerotised cuticle around ventrianal shield with eight pairs of opisthogastric setae [JV4 46 (45–50), JV5 94 (86– 110), ZV1 34 (31–37), ZV2 38 (35–42), ZV3 35 (32–37), ZV4 36 (35–38), ZV5 37 (35–40), SV 33 (30–35) and three pairs of lyrifissures. Discrete endopodal shield absent. Exopodal shield narrow, extending from posterior region of coxa II to anterior region of coxa IV. Peritremal shield narrow, extending anteriorly to level of s1 and posteriorly to region behind coxa IV; lyrifissure evident. Peritreme short, 31 (30–32) long, reaching posterior margin of coxa III.

Spermatheca ( Fig.5 C): calyx horn–like, variously constricted near vesicle; atrium globular.

Gnathosoma: Fixed cheliceral digit 20 (17–22) long, with three teeth in addition to apical tooth and setiform pilus dentilis ( Fig. 5 D); movable cheliceral digit 30 (30–31) long, distinctly longer than fixed digit, with a tooth in addition to apical tooth. Anterior margin of epistome smooth, with small rounded median lobe ( Fig. 5 E). Corniculi tapered and convergent. Deutosternal denticles not distinguishable ( Fig. 5 F). Numbers of setae on palpal segments normal for suborder Gamasina ( Evans, 1964) , from trochanter to genu: 2, 5 and 6 setae; tibia and tarsus, not counted. Apotele bifurcate. Hypostomal and subcapitular setae setiform: h1 19 (17–22), h2 24 (22–25), h3 27, subcapitular (Sc) 29 (28–30).

Legs: pretarsi of legs I–IV consisting of elongate stalk, a pair of claws and pulvillum with three rounded lobes. Lengths of legs: I, 386 (360–400); II, 295 (280–320); III, 279 (270–290); IV, 345 (335–360). Numbers of setae on leg segments normal for suborder Gamasina ( Evans, 1963) : coxa, 2, 2, 2 1; trochanter, 6, 5, 5, 5; femur, 12, 11, 6, 6; genu, 13, 11, 9, 9; tibia, 13, 10, 8, 10; tarsi II–IV, 18, 18, 18 ( Fig. 5 G). Tarsus I 2.7 times as long as tibia I. Macrosetae absent.

Adult males ( Fig.6 A–F) (four specimens examined).

Dorsum of idiosoma ( Fig. 6 A): dorsal shield reticulate, 373 (360–383) long and 180 (172–188) wide at s4. Podonotal region of dorsal shield with 18 pairs of setae [j1 14 (12–15), j2 21 (20–25), j3 31 (30–31), j4 31 (30–33), j5 31 (30–33), j6 32 (31–33), z1 14, z2 32 (30–34), z3 31 (30–32), z4 37 (36–40), z5 31 (30–31), z6 31 (30–32), s1 24 (23–25), s2 29 (28–30), s3 31 (30–32), s4 37 (36–38), s5 34 (32–36), s6 34 (33–35)], five pairs of lyrifissures and four pairs of pores. Opisthonotal region with 15 pairs of setae [J1 33 (31–35), J2 34 (33–35), J3 32 (30–34), J4 34 (32–37), J5 22 (21–24), Z1 35 (33–36), Z2 35 (33–35), Z3 31 (30–32), Z4 36 (35–38), Z5 52 (50–55), S1 32 (31– 32), S2 33 (32–34), S3 34 (30–36), S4 34 (31–36), S5 30 (28–31)], nine pairs of lyrifissures and two pairs of pores. Unsclerotised cuticle along dorsal shield with eleven pairs of marginal setae [r2 28 (25–30), r3 32, r4 30 (29–31), r5 33 (32–33), r6 31 (29–33), R1 31 (30–31), R2 27, R3 27 (25–28), R4 29 (27–30), R5 28 (25–30), R6 29 (28–30)], six pairs of submarginal setae [UR1 26 (25–26), UR2 24 (22–25), UR3 23 (22–23), UR4 24 (23–25), UR5 23 (21– 25), UR6 24 (22–26)] and two pairs of lyrifissures.

Venter of the idiosoma ( Fig. 6 B): all setae setiform. Base of tritosternum 7 long and 12 (10–12) wide; laciniae free for approximately 65% of their total length of 54 (50–60). Sternogenital shield 165 (164–168) long and 71 (70–75) wide at the level of st2, with scarce reticulation in the central region and with narrow projections between coxae I–II and III–III; with slight indentation behind st4, with four pairs of setae and three pairs of lyrifissures; st5 on unsclerotised cuticle; lyrifissure near st5 not distinguishable. Ventrianal shield approximately hemispherical, reticulate, 153 (150–160) long and 164 (158–165) wide anterolateral angles; with punctate area (cribrum) behind anal opening; with six pairs of opisthogastric setae (JV1, JV2, JV3; ZV1, ZV2, ZV3), three pairs of lyrifissures and a pair of pores on the lateral margin, approximately in level with the posterior margin of anal opening; para–anal seta [19 (18–20)] slightly shorter than post–anal seta [23 (21–25)]. Unsclerotised cuticle around ventrianal shield with three pairs of opisthogastric setae [JV5 101 (95–105), ZV4 39 (30–60), ZV5 43 (40–50)] and three pairs of lyrifissures. Discrete endopodal shield absent. Exopodal shield narrow, extending from anterior region of coxa II to posterior region of coxa IV. Peritremal shield similar to that of adult females, but with a narrow, transversely ridged strip externally to the peritreme, which is 22 (21– 22) long.

Gnathosoma: Fixed chelicera digit 21 (20–21) long, with two (most commonly) or three teeth in addition to apical tooth and setiform pilus dentilis ( Fig. 6 C); movable cheliceral digit 25 (24–25), with one tooth in addition to apical tooth. Spermatodactyl distally curved, with a membrane along dorsal surface, a ventral subterminal spine–like projection and concave apex, 20 (18–21) long. Epistome similar to adult females ( Fig. 6 D). Corniculi more widely spaced than in adult females, convergent. With seven rows of deutosternal denticles, with two teeth on each of the first 3 rows and one tooth on other rows ( Fig. 6 E). Numbers of setae on palpal segments, hypostomal and subcapitular setae, as in adult females. Setae h1 14 (13–15), h2 14, h3 23, Sc 25 (22– 26), setiform.

Legs: pretarsi of legs I–IV as in adult females. Lengths of legs: I, 324 (310–330); II, 252 (240–260); III, 231 (215–240); IV, 303 (285–315) ( Fig. 6 F). Numbers of setae on leg segments as in adult females. Tarsus I 2.2 times as long as tibia I.

Figures

FIGURE 5. Blattisocius keegani, adult female. A. Dorsal view; B. Ventral view; C. Spermatheca; D. Chelicera; E. Epistome; F. Venter of gnathosoma; G. Tarsus of leg IV.

FIGURE 6. Blattisocius keegani, adult male. A. Dorsal view; B. Ventral view; C. Chelicera and Spermatodactyl; D. Epistome; E. Venter of gnathosoma; F. Tarsus of leg IV.