Castriidinychus longisetosus, Dylewska & Błoszyk & Halliday, 2010

Dylewska, M., Błoszyk, J. & Halliday, R. B., 2010, Three new species of mites in the genus Castriidinychus Hirschmann from Tasmania (Acari: Uropodidae), Zootaxa 2546 (1), pp. 1-30 : 12-20

Castriidinychus longisetosus sp. nov.

Material examined. Tasmania. Holotype. Female. Mt. Mangana, Bruny Island , site 2, moss on log, 43°21'S 147°13'E, 9.iv.89, P. Greenslade coll., TAS-205 (in ANIC) . Paratypes. Tasmania. 4 females, 6 males, same data as holotype; 2 females, 1 DN, Mt. Mangana, Bruny Island, site 1, litter, 43°21'S 147°13'E, 9.iv.89, P. Greenslade coll. TAS-036; 2 females, 2 males, Mt. Mangana , Bruny Island , site 1, litter, 43°22'S 147°17'E, 9.iv.89, P. Greenslade coll., TAS-135; 8 females, 5 males, Mt. Mangana , Bruny island , site 1, dead wood, 43°22'S 147°17'E, 9.iv.89, P. Greenslade coll., TAS-136; 7 females, 8 males, 2 DN, Mt. Mangana , Bruny island , site 2, litter, 43°22'S 147°17'E, 9.iv.89, P. Greenslade coll., TAS-138; 5 females, 3 males, Mt. Mangana , Bruny Island , site 2, moss on dead log, 43°21'S 147°13'E, 4–9.iv.89, J. Diggle and P. Greenslade coll., TAS-158; 2 females, 6 males, Mt. Mangana , Bruny Island , site 2, litter, 43°21'S 147°13'E, 10.iv.89, P. Greenslade coll., TAS-160; 1 female, Mt. Mangana , Bruny Island , moss sample 1d, 43°21'S 147°13'E, 09.iv.89, J. Diggle coll., TAS-196; 9 females, 4 males, 1 DN, Mt. Mangana , Bruny Island , moss sample 1b, 43°21'S 147°13'E, 9.iv.89, J. Diggle coll., TAS-197; 4 females, 7 male, Mt. Mangana , Bruny Island , moss sample 1a., 43°21'S 147°13'E, 9.iv.89, J. Diggle coll., TAS-198; 1 female, 1 male, Mt. Mangana , Bruny Island , moss sample 1c, 43°21'S 147°13'E, 09.iv.89, J. Diggle coll., TAS-199; 1 female, 6 males, 3 DN, Mt. Mangana , Bruny Island , site 2, litter, 43°21'S 147°13'E, 4.iv.89, J. Diggle and P. Greenslade coll., TAS-203; 2 females, 2 males, 2 DN, Mt. Mangana , Bruny Island , 147º17'E 43º22'S, 9.iv.89, P. Greenslade coll., TASII/4 ; 2 males, 3 females, Pirates Road, Tasman Peninsula, 2.5 km SW of Eaglehawk Neck, south track, Nothofagus cunninghamii , moss at base of myrtle trunk, 43°03'S 147°55'E, 21.iii.89, J. Diggle coll., TAS-047; 1 female, 4 males, Pirates Road, Tasman Peninsula, 2.5 km SW of Eaglehawk Neck, south track, Nothofagus cunninghamii , litter, 43°03'S 147°55'E, 21.iii.89, P. Greenslade and J. Diggle coll., TAS-052; 1 male, Big Sassy Creek , 21 km NNW of Little Swanport, site 1, rotten log, 42°09'S 147°55'E, 17.v.89, J. Diggle coll, TAS-113; 4 females, 14 males, Big Sassy Creek , 21 km NNW of Little Swanport, site 1, moss, 42°09'S 147°55'E, 17.v.89, P. Greenslade coll., TAS-118; 1 female, 1 male, Big Sassy Creek , 21 km NNW of Little Swanport, site 1, litter, 42°09'S 147°55'E, 12.v.89, P. Greenslade coll., TAS-190; 1 female, Big Sassy Creek , 21 km NNW of Little Swanport, site 1, litter, 42°09'S 147°55'E, 12.v.89, P. Greenslade coll., TAS-193; 1 female, 2 males, 1 DN, Big Sassy Creek , 21 km NNW of Little Swanport, site 2, litter, 42°09'S 147°55'E, 17.v.89, P. Greenslade coll., TAS-195; 1 female, 4 males, Sandspit River , Forestry Reserve , litter, 42°42'S 147°52'E, 22.v.89, P. Greenslade coll., TAS-130; 1 female, Simons Road, soil cores, 41°21'S 147°31'E, 5.vi.89, P. Greenslade coll., TAS-168; 1 female, 1 male, Old Farm Road, Mount Wellington , Eucalyptus forest, litter, 42°54'S 147°14'E, 20.vi.89, P. Greenslade coll., TAS-183; (in AMU and ANIC) .

Female. Dorsal idiosoma ( Figs 12 , 13 ). Length 554–592 µm (mean 577 µm), width 346–415 µm (mean 384 µm) (n = 13). Dorsal shield oval, ornamented with sparsely scattered small circular pits. Vertical setae j1 long (62–72 µm), serrated, other dorsal shield setae numerous, mostly long and massive (32–44 µm), with variable numbers of much shorter (15–17 µm) setae in medial region, often asymmetrical; three pairs of posterior setae inserted on small mounds, 30–49 µm long. Marginal shield narrow, clearly demarcated from dorsal shield; four pairs of anterior marginal setae z1, s2, r2, r3 very long (49–67 µm), serrated ( Fig. 13D ).

Ventral idiosoma ( Figs 5B , 14 , 15 , 16 ). Tritosternum with narrow base and four forked laciniae. Sternal shield smooth anteriorly, posterior section behind st2 ornamented with irregular oval pits, most strongly developed in endopodal area between coxae III – IV. Sternal/genital region with four pairs of subequal simple sternal setae, one near camerostome and three lateral to epigynal shield. Epigynal shield tongue-shaped, articulated at level of coxae IV, surface smooth, length 125–141 µm (mean 129 µm) width 71–86 µm (mean 80 µm) (n = 13). Ventral opisthosoma mainly smooth, central area behind epigynal shield with weak punctate ornamentation; with six pairs of ventri-anal setae, most posterior pair longest (47 µm), serrated. Anal opening small, oval, flanked by two pairs of adanal setae, Ad1 shorter than Ad2, post-anal seta Pa longer, serrated. Submarginal ventral setae long and serrated, last pair very long, 62 µm. Peritreme with distinctive convoluted shape ( Fig. 16A ), stigmata at level of coxa II.

Gnathosoma ( Fig. 8C ). Hypostomal setae h1 very long (32 µm) and smooth, h2 shorter (18 µm), massive and serrated, h3 shorter than h1 (28 µm), medially serrated, h4 shortest (16 µm), distally serrated.

Legs. Leg chaetotaxy as in Figure 17 . All leg setae smooth and pointed, some dorsal and lateral setae on tarsus II, III, IV short, thick, spine-like.

Male. Dorsal idiosoma ( Fig. 19A ). Length 554–615 µm (mean 586 µm), width 354–415 µm (mean 388 µm) (n = 12). Structure and chaetotaxy as for female.

Ventral idiosoma ( Fig. 18 , 19B, 19C ). Anterior and central parts of intercoxal region smooth, marginal strip adjacent to coxae and posterior area around genital operculum slightly ornamented; with five pairs of short simple sternal setae, shorter than those of female. Setae st4 and st5 situated lateral to genital operculum. Genital operculum oval, smooth (57–65 x 35–59 µm), without setae. Chaetotaxy and sculpture of opisthosoma as in Fig. 18 , anterior pair of opisthosomal setae inserted very close to last pair of sternal setae st5.

Gnathosoma . Hypostomal surface smooth, except for two longitudinal rows of tiny denticles ( Fig. 8D ). Hypostomal setae h1 more massive than others, long (23 µm), h2 shortest (15 µm), serrated, h3 longest (39 µm), medially serrated, h4 short (18 µm), distally serrated.

Legs. As for female.

Deutonymph. Dorsal idiosoma ( Fig. 11C ). Length 485–556 µm (mean 504 µm), width 315–425 µm (mean 344 µm) (n = 9). Dorsal shield smooth with numerous setae of two types, mostly long but some medial and marginal setae much shorter. Marginal shield narrow, with two pairs of long anterior setae and 5–6 pairs of much shorter setae.

Ventral idiosoma ( Fig. 11D ). Sternal shield elongate, sharply narrowed between coxae IV; surface smooth, with five pairs of simple sternal setae and two pairs of lyrifissures. Peritrematal, metapodal and pericoxal shields fused. Ventri-anal shield trapezoidal, smooth, with six pairs of ventral setae, anterior pair and one lateral pair long, others much shorter, two pairs of adanal setae, Ad1 short, Ad 2 very long, and short unpaired post-anal seta Pa. Anal opening small and oval, without morphological modification for phoresy. One pair of simple opisthosomal setae inserted in soft skin lateral to ventri-anal shield, and another longer pair posterior to ventri-anal shield. Peritreme long, slightly curved, with short post-stigmatic section; stigmata situated at level of coxae II.

Etymology. The name of this species refers to the long marginal and submarginal setae on the idiosoma of the female.

Notes. Castriidinychus longisetosus occurred at scattered localities in eastern Tasmania (Fig. 24), in mixed forest types dominated by Eucalyptus , in moss and leaf litter under Eucalyptus and Nothofagus , in rotting logs, and in a soil core. It was the most abundant of the three species studied here, with more than ten specimens found in a small sample on a number of occasions.

Figures

FIGURE 5. Castriidinychus spp., females, intercoxal area and genital shield. A, C. tasmanicus; B, C. longisetosus; C, C. robynae. Scale bar 100 µm.

FIGURE 8. Castriidinychus spp., hypostome. A. C. tasmanicus female; B. C. tasmanicus male; D, C. longisetosus female; D, C. longisetosus male; E, C. robynae female. Scale bar 50 µm.

FIGURE 11. Castriidinychus spp., deutonymph. A, C. tasmanicus, dorsal idiosoma; B. C. tasmanicus, ventral idiosoma; C, C. longisetosus, dorsal idiosoma; D, C. longisetosus, ventral idiosoma. Scale bar 100 µm.

FIGURE 12. Castriidinychus longisetosus, female, dorsal idiosoma. Scale bar 100 µm.

FIGURE 13. Castriidinychus longisetosus, female. A, dorsal idiosoma; B, postero-dorsal idiosoma; C, lateral habitus; D, antero-marginal setae.

FIGURE 14. Castriidinychus longisetosus, female, ventral idiosoma. Scale bar 100 µm.

FIGURE 15. Castriidinychus longisetosus, female. A, ventral idiosoma; B, intercoxal region and genital shield.

FIGURE 16. Castriidinychus longisetosus, female. A, peritreme; B, postero-ventral idiosoma; C, legs III and IV and pedofossae.

FIGURE 17. Castriidinychus longisetosus, female, A. leg I, B. leg II, C. leg III, D. leg IV. Black setae are visible when the specimen is examined ventrally, with the legs in their natural folded position. Scale bar 100 µm.

FIGURE 18. Castriidinychus longisetosus, male, ventral idiosoma. Scale bar 100 µm.

FIGURE 19. Castriidinychus longisetosus, male. A. antero-lateral habitus; B, ventral idiosoma; C, intercoxal region.