Pedetontinus taishanensis, Zhang & Zhou, 2011

Zhang, Jiayong & Zhou, Kaiya, 2011, Descriptions of one new genus and six new species of Machilidae (Insecta: Archaeognatha) from China: morphological and molecular data, Journal of Natural History 45 (19 - 20), pp. 1131-1164 : 1154-1157

Pedetontinus taishanensis sp. nov.

Material examined

Holotype. NNUSB0216 , an adult male; China: Mt Taishan , Taian County, Shandong Province, on wet granite rocks covered with moss, 36 ◦ 16 ′ N, 117 ◦ 6 ′ E, at an elevation of 800 900 m, 25 August 2005, coll. J.Y. Zhang.

Paratypes. NNUSB0217–0223 , seven adult males ; NNUSB0224–0227 , four adult females; same data as for holotype .

Males

Body length 8.0– 8.5 mm; antennae: 6.8–7.5 mm; terminal filament: 9.0– 9.5 mm; cerci: 4.1–4.5 mm. Body brownish grey, covered densely with scales and with pigments. Terga mostly covered with brown scales. No spots present on terga. Few epidermic pigment on head capsule, labial, maxillae and legs.

Head ( Figure 7A ) pale between two antennae. Clypeus covered with numerous short, thin setae. Frons convex moderately, scaled between antennae and ocelli, with two long setae and two short setae on frons.

Compound eyes large, black or brownish black (in alcohol), contact line/length: 0.66–0.70; length/width: 0.98–1.00. Paired ocelli shoe-shaped, enlarged in submedian area, reddish brown (in alcohol). Ocellus with white edge and an inner zonal white area in enlarged area, one short seta present in white area of ocellus; width of ocellus slightly narrower than that of compound eye (width of ocellus about 0.77–0.79 that of compound eye).

Antennae shorter than body length, antennal length/body length about 0.80– 0.91. Scapus and pedicellus of antennae densely scaled; flagellum not scaled. Scapus rather long (length/width about 2.00), pedicellus as long as wide. Flagellum uniformly brownish, junctions between divisions pale. Division of flagellum maximum observed 37, proximal 16 divisions not annulated, divisions 17–21 with two to four annuli and divisions 22–37 with seven to nine annuli. The distal chains ( Figure 7E ) with eight or nine annuli, which are about thrice as wide as long.

Mandibles quite robust, provided with four typical apical teeth. Maxillary palp ( Figure 7C,D ) provided with numerous setae of moderate size. Setae in articles V – VII denser than those in articles I–IV. Articles II – VII scaled densely. External apophysis of article I cone-shaped, slightly curved backwards with long setae sparsely on ventral surface. Article II is curved inwards, not extending beyond article III and with eight to ten light setae on its ventral surface and without setae on its dorsal surface. Article III with dense short setae on ventral surface and three spines on internal distal end, article VII cone-shaped. Dorsal surface of the articles V – VII with hyaline spines as follows: V: 4–6; VI: 10–12; VII: 8–10. Ratio of length article VII / VI: 0.60–0.61; article IV/ V: 0.66–0.68.

Labial palp as in Figure 7B , article I no scale, II – III sparsely scaled; article III almost club like, with sensorial cones on apical part.

Legs ( Figure 7F–H ) and coxal stylets scaled. Mid and hind legs with coxal stylets. Femur of fore leg not swollen, ratio of length to width: 2.0. Spiniform setae present on femur, light-coloured. Length of tibia I: 0.60–0.66 mm; tibia II: 0.68 mm; tibia III: 0.65–0.66 mm. Fore legs stronger than others, tibia of hind legs not obviously elongated. Spines in legs as follows: tibia I: 1–2; tibia II: 2–4; tibia III: 2–4; number of 1–3 segments of tarsus I: 4–6, 10–14, 10–12; tarsus II: 4–6, 10–14, 10–12; tarsus III: 4–6, 10–14, 10–12.

Urosternites not pigmented. Abdominal stylets not especially elongated except IXth segment. Abdominal segments I– VII with a pair of eversible vesicles. Sternum V ( Figure 7I ) nearly right posterior angle (87–89 ◦); length/basal width of sternum V: 0.66–0.67. Sternum VII without swollen on its inner posterior part.

A penis and a pair of parameres ( Figure 7J ) with 1+6 divisions (or 7 divisions) extending backward to two-thirds of length of the urosternite IX. Penis normal, slightly longer than paramere, ratio of the length of base/tip: 2.0–2.2, opening of penis small and apical. Male genitalia completely covered by the IXth urosternite. Apical spine of abdominal stylets strong, medium-sized. IXth coxite provided with five to seven spines near apex. Length ratios of stylet (excluding apical spine) to coxite, V: 0.59; VIII: 0.60; IX: 0.60; length ratios of apical spine to stylet, V: 0.48–0.50; VIII: 0.40–0.43; IX: 0.31–0.34.

Terminal filament and cerci without piliform scales, with numerous scales.

Females

Body length 8.5–9.5 mm; antennae: 5.6–6.3 mm; terminal filament: 7.8–8.5 mm; cerci: 3.6–4.0 mm. Scale pattern and epidermic pigment as in male.

Head as in male ( Figure 7K ). More setae present in the labrum and the clypeus. Compound eyes large, black or brownish black (in alcohol), contact line/length: 0.60– 0.63; length/width: 0.98–1.00. Paired ocelli as in male, their width about 0.74–0.77 of that of compound eye.

Antennae as in male. Antennal length/body length about 0.77. Division of flagellum maximum observed 34, proximal 15 divisions not annulated, divisions 16–21 annulated into two to four annuli, divisions 22–34 with six to eight annuli. The distal chains ( Figure 7O ) with seven or eight annuli, which are about as wide as long. The distal chains with sensilla and sensorial points.

Maxillary palp ( Figure 7M,N ) as in male. Articles II – VII scaled densely, article I only with scales on ventral surface; dense setae on articles IV– VII, and article VII cone-shaped. Dorsal surface of the articles V – VII with hyaline spines as follows: V: 4–6; VI: 12–14; VII: 10–14. Ratio of length article VII / VI: 0.61–0.63; article IV/ V: 0.64–0.67.

Labial palp as in male ( Figure 7L ).

Legs ( Figure 7P–R ) as in male. Femur of fore leg not swollen, ratio of length to width: 1.40–1.50. Length of tibia I: 0.57–0.60 mm; tibia II: 0.56–0.60 mm; tibia III: 0.71–0.76 mm. Fore legs stronger than others, the tibia of hind legs elongated. Spines in legs as follows: tibia I: 2–4; tibia II: 2–4; tibia III: 2–4; number of 1–3 segments of tarsus I: 2–4, 6–8, 10–14; tarsus II: 2–4, 6–8, 10–14; tarsus III: 2–4, 6–8, 10–14.

Abdominal segments as in male. Sternum V with nearly right posterior angle (85–87 ◦); length/basal width of sternum V ( Figure 7S ): 0.66–0.67. Medial part of urosternite VII projected and swollen, exceeding posterior margin ( Figure 7T ).

Ovipositor of the tertiary type and slightly exceeding beyond the stylet of urosternite IX. Gonapophysis VIII ( Figure 7U–W ) with 49–52 divisions, with sensilla except 3–4 basal divisions. Gonapophysis IX ( Figure 7X–Z ) with 50–52 divisions, the basal 20–22 divisions with some short setae. IXth coxite provided with eight or nine spines near apex. Length ratios of stylet (excluding apical spine) to coxite, V : 0.57; VIII: 0.70; IX: 0.54; length ratios of apical spine to stylet, V: 0.64–0.66; VIII: 0.49–0.50; IX: 0.30–0.35.

Terminal filaments and cerci similar to those of male.

Etymology

The specific name refers to the type locality.

Figures

Figure 7. Pedetontinus taishanensis sp.nov. Male (A–J): (A) head, frontal view, (B) labium, (C) maxillary palp, (D) apical spines of article VII, (E) the distal chains of flagellum, (F) fore leg, (G) mid leg, (H) hind leg, (I) urosternite V, (J) urosternite IX with paramere and penis. Female (K–Y): (K) head, frontal view, (L) labium, (M) maxillary palp, (N) apical spines of article VII, (O) the distal chains of flagellum, (P) fore leg, (Q) mid leg, (R) hind leg, (S) urosternite V, (T) urosternite VII, (U) urosternite VIII with anterior gonapophysis, (V, W) part of gonapophysis VIII, ventral view, (X) urosternite IX with posterior gonapophysis, (Y, Z) part of gonapophysis IX, ventral view.