Pedrocortesella nortoni, Hunt, 1996

Hunt, Glenn S., 1996, A review of the genus Hexachaetoniella Paschoal in Australia (Acarina: Cryptostigmata: Pedrocortesellidae), Records of the Australian Museum 48 (3), pp. 223-286 : 269-271

Pedrocortesella nortoni n.sp.

Figs 34-36

Type material. Tasmania: HOLOTYPE adult. ANIC, Cradle Mountain Camping Ground, 41°35'S 145°55'E, 880 m, pyrethrum knockdown from trees, H. Mitchell, 15 November 1989 . PARATYPE adults. AM KS43746 , same data as holotype, 1 adult . AM KS46569 SEM stub no. 274 (ill.), Cradle Mountain Camping Ground, 41°35'S 145°55'E, pyrethrum knockdown from trees, R. Coy, 17 November 1989, 1 adult ; AM KS46570 SEM stub no. 275 (ill.), same data, 1 adult .

Diagnosis. Body medium, length about 450-500 /-lm; scalps loosely carried by adult and may be missing; sensillus terminates in rounded club not flattened blade; notogaster foveate, 5 pairs notogastral setae, with cerotegument they are leaf-shaped; mental tectum present; genitoanal chaetotaxy 7:1:2:2; both adanal setae near posterior margin of anal valve; claw stalk very short.

Description

ADULT: Body: brown; length 470 /-lm, 480 /lm. Cerotegument: body generally with thin veneer of cerotegument; reticulations on prodorsum and notogaster with numerous cushion-like grains of cerotegument (Fig. 36D). Setae le and notogastral setae with thick lateral fringes of cerotegument giving the seta a tapering appearance (Fig. 34G); ro with cerotegument at its base. Prodorsum: integument more or less uniformly reticulatefoveate including area between bothridia; foveae without visible pores; carina between le and ro absent; le dorsolateral and situated close to anterior of rostrum, distance between them about 0.4 distance between ro, ro ventrolateral, insertion just visible from above. Pedotectal tooth strongly curved anteriad, tapering abruptly near its base into a long spine. Bothridium abutting notogaster but not closely adpressed (Fig. 34F), wall oval; posterolateral carina moderate, close to notogaster; sensillus length about 0.3 interbothridial distance, and rounded, densely tuberculate (Fig. 34E); posterior margin of prodorsum forming a smooth arc between bothridia; in small, its supporting apophysis abutting bothridial base; just inside edge of dorscisejugal furrow, spiniform, base encased in cerotegument (Fig. 34C,E). Exuvial scalps: loosely carried or lost; anterior margins of scalps not tightly compressed against neighbouring ones. Notogaster: oval, length:width without scalps 340:250. Intramarginal depression similar in shape to P. propinqua . Notogaster strongly foveatereticulate, not perforated by pores (Fig. 36D); posterior margin not invaginate when viewed from above, without carina between setae pI when viewed posteriorly (Fig. 36B). Fissura ia and im oblique to sagittal plane, ip subperpendicular; 5 pairs of short notogastral setae (Fig. 36A), with thick cerotegument coating, arising from small pits; hi moderately separated, each located at posterior margin; pi inserted about mid-height on posterior flank, slightly closer together than hi; lpx, p2x and p3x arise along posterolateral flank, their insertions seen from above, lpx closest to fissura ip, inserted just posterior to it (Figs 34A, 36A). Gnathosoma : rutella basally with weak concave flexure and moderate lateral buttressing, weak transverse striations present (Fig. 36E). Pedipalp tarsus with setae (vt) with short side branches, cm branches very short; I" smooth; apophysis supporting seta aem weak, <0.5 seta length; solenidion omega reaching to base of aem (Fig. 35C). Epimeral region: weakly convex anterior to genital valves, not tending to overhang them. Epimeral chaetotaxy 3,1,3,3. Genitoanal region: separation of anal and genital vestibules relatively broad but with interruption to ventral plate microsculpture, wide mesal isthmus without strong transverse grooves between the vestibules (Fig. 35A), Ventral plate reticulate-foveate. Genitoanal chaetotaxy 7,1,2,2; genital setae essentially in straight file (Fig. 35D); gi inserted at anterior corner of valve in marginal notch; g7 inserted well anterior to inner posterior corner, in marginal notch; setae ag inserted at level posterior to g7; setae adi distinctly postanal, ad3 presumably not present. Legs. Apophysis of tibia I overrides about 0.5 of tarsus (Fig. 36C). Tarsal cluster of leg I placed distodorsally on apophysis, fi", omega i and 2 enclosed in common rim (Fig. 36F), no partition separating fi" from omega i and 2, latter close together, fi" with heavy cerotegument at base; opening of cavity containing undeveloped seta epsilon not seen; tarsus without dista1 recess for receiving retracted unguinal complex, stalk very short.

Comments. This species resembles P leei in having two pairs of adanal setae but differs in having seven pairs of genital setae, an ovoid, clavate sensillus, and a weakly developed mental tectum. It resembles P enigma in having a clavate sensillus and transverse striations on the rutella but differs in only having two pairs of adanal setae and two pairs of anal setae.

Etymology. This species is named for Professor Roy Norton's in recognition of his contribution to acarology,. and the encouragement he has given me.

Distribution. Known only from the type locality, northwestern Tasmania.