Scaptognathides delicatulus Bartsch, 2004

Pepato, Almir R., Tiago, Cláudio G. & Rocha, Carlos E. F., 2011, Psammophilous halacarid mites (Trombidiformes, Halacaridae) from the North Coast of São Paulo State, Brazil, Zootaxa 2823, pp. 47-60 : 48-50

Scaptognathides delicatulus Bartsch, 2004

( Figs. 1–2 )

Scaptognathides delicatulus Bartsch, 2004b: 6 , figs. 17–25

Material examined. 1 female (MZSP-AC68), 1 female (Pepato´s collection), 3 protonymphs (MZSP-AC70– MZSP-AC72) and 2 protonymphs (Pepato´s collection), 20–30 cm, São Francisco Beach, 27 May 2002; 1 female (MZSP-AC69), 40–50 cm, same locality and date; 2 females (Pepato´s collection), 10–20 cm, same locality and date; 1female (Pepato´s collection), 23–37 cm, same locality, 14 January 2002; 1 female (Pepato´s collection), 40– 50 cm, same locality, 15 March 2002. All mites collected by researchers of BIOTA /FAPESP Program.

Description. Measurements summarized in Table 1.

Female Protonymph

Length Width Length Width Idiosoma 155–168 86–100 140–141 83–94 Gnathosoma 73–79 43–45 66–67 32–36 AD 56–61 63–68 46–49 54–56 PD 88–93 60–68 64–65 53–55 OC 23–29 11–13 23–25 10–12 AE 55–63 86–95 54–58 72–77 GA 73–68 53–59 48–49 40–41 GO 29–30 11–16 --- --- Female. Dorsal plates with delicate pits, except 1 female with faint reticulation on PD. Pairs of ds-1–ds-3 and gp-1 situated on AD, but one of ds-3 on striated cuticle in 1female. Pairs of gp-2 and gp-3 on anterior and posterior corners of OC, respectively. Pairs of ds-4 and ds-5 on PD. Fourth pair of gland pores also on PD, approximately at level of insertion of leg IV. Pair of gp-5 on cone-like projection, on posterior portion of PD. AD: PD = 0.60–0.69. Adanal setae dorsally on anal papilla.

Ventral plate surfaces almost smooth, with panels on lateral margins of PE. AE with 3 pairs of setae. Conspicuous epimeral processes at insertion of leg I and II. PE with 1 dorsal 3 ventral setae, 84–90 μm long, surpassing insertion site of leg IV. GA with 2 pairs of pgs. Anterior margin of GA 0.47–0.58 times as wide as its maximum width. Distance from anterior margin of GA to GO 1.23–1.48 times of GO length. Genital sclerites with 1 pair of sgs.

Gnathosoma 0.46–0.51 times length of idiosoma. Rostrum parallel-sided, 45 long, 7 wide, and 0.55–0.60 of gnathosomal length. Basirostral setae short, smaller than tritorostral setae.

Leg chaetotaxy: legs I and II: 1,2,4,4,5,3; legs III and IV: 1,2,2,3,5,3. Telofemur I 3.1 times longer than width (2 females measured), faintly ornamented by elongated shallow foveae. Paired claws of legs II to IV slender and smooth. Medial claws absent.

Protonymph. Dorsal plates faintly reticulated. Pair of ds-1 on AD. Pairs of ds-2 to ds-4 on membranous cuticle. Pair of ds-5 on PD. Distribution of gland pores similar to female.

Posterior epimeral plate with 1 ventral and 1 dorsal seta. Genitoanal plate without setae. One pair of genital acetabulae visible underneath GA. Leg chaetotaxy: legs I and II: 1,2,3,4,5,3; leg III: 1,2,2,3,5,3; leg IV: 0,2,3,5,3.

Remarks. Scaptognathides delicatulus Bartsch, 2004 , a species described from the Persian Gulf, displays a unique combination of traits: two gland pores on OC, ornamentation on dorsal plates composed by scattered shallow pits, three setae on tarsus III, four setae on telofemora III and IV and a pair of sgs present on female genital sclerite ( Bartsch 2004b). Despite of the occurrence of a faint reticulation on PD in a single Brazilian female, no remarkable differences could be found between Bartsch's original description and the material studied. As this ornamentation is observed in protonymphs, it is believed to be a paedomorphic abnormality.

Figures

FIGURE 1. Scaptognathides delicatulus Bartsch, 2004, female: A, dorsum of idiosoma; B, venter of idiosoma; C, detail of AD close to ds- 1; D, gnathosoma in ventral view; E, leg I in lateral view; F, leg II in medial view; G, leg IV in lateral view; H, leg III in lateral view. Scale bars: A, B, D – H = 25 µm; C = 10 µm.

FIGURE 2. Scaptognathides delicatulus Bartsch, 2004, protonymph: A, dorsum of idiosoma; B, venter of idiosoma; C, leg I in lateral view; D, leg IV in medial view; E, leg II in medial view; F, leg III in lateral view. Scale bars = 25 µm.