Validifemur pedodontus, Song, Hui-Qin Ma Da-Xiang & Zhu, Ming-Sheng, 2007

Song, Hui-Qin Ma Da-Xiang & Zhu, Ming-Sheng, 2007, A new genus and two new species of Lithobiid Centipedes (Chilopoda: Lithobiomorpha) from China, Zootaxa 1460, pp. 25-34 : 26-30

Validifemur pedodontus sp. n.

Figs. 1–10

Diagnosis: Maximum body length (from the anterior margin of the head shield to the posterior end of telson) up to 11.7 mm, antennae composed of 18–26 antennomeres, commonly 20; 6–8 ocelli on each side, usually 7; Tömösváry’s organ moderately large, rounded, ca. equal to adjoining ocelli; 2+2 prosternal teeth; porodonts feebly thicker, posterolateral to lateral tooth; posterior angles of all tergites rounded; female gonopods with 2+2 moderately small, coniform spurs, and tridentate claw, the middle is the largest, the ventral and the dorsal very small. Male legs 15 prominently developed and very thick; prefemur very short, of unusual crassitude, a very strong internal protuberance in dorsal view of prefemur; a inner bulge on the basal half of the tibia, 11 falciform thorns on the protuberance, forming an ellipse; leg spinulation pattern and number of coxal pores are different on legs 15 in the two sexes, four or three coxal pores are present in the last pair of legs of the female, only two coxal pores in male.

Holotype: Female ( Fig. 1 ), body length 11.7 mm, from Mazhao town, Zhouzhi County, Shanxi Province, 34 0 03'45.9" N 108 0 11 '39.9"E, 541 m, 12 October 2005, leg, Hui-Qin Ma.

Paratypes: 6 females, 9 males, same locality as holotype.

Etymology: The specific name refers to the inner falciform thorns on the protuberance of the tibia of the anal legs.

Habitat preferences: The type series has been collected in low mountain environments without forest.

Distribution: Shanxi Province (Zhouzhi County).

Description: Body length 10.1–11.7 mm; width of the head shield 1.07–1.34 mm, about as long as wide.

Color (based on specimens in 75% ethanol): antennae deep red-brown, terminal antennomere yellowbrown; tergites red-brown to dark red-brown; with pale white mottling concentrated in a longitudinal median band; the head shield and the last two tergites are darker; pleural region and sternite lavender to grey, with reddish hue in some specimens; maxillipede coxosternum and T 14 and T 15 of dust color to red-brown; all legs of dust color, distal tarsus yellow-brown; legs of 14 and 15 of dust color with reddish hue, genital sternite yellow-brown.

Antennae of 18–26 antennomeres, commonly 20; basal antennomere slightly longer than wide, following antennomeres typically longer than wide; length of antennomeres gradually shorter beginning with the second antennomere, those of the distal part slightly to markedly elongate, terminal antennomere up to about three times as long as wide.

Antennae as long as 3.3–3.8 times the width of the head shield, usually extending back to posterior of T 4 or anterior of T 5. Abundant setae inserted on antennal surface, fewer setae on both ventral and dorsal side in basal antennomeres, gradually increasing in density to about seventh or eighth antennomere, then more or less constant.

Head shield smooth, back hunched; frontal marginal ridge with shallow anterior median furrow; posterior margin of head shield straight, border variably slightly wider posteromedially than posterolaterally, posterior marginal ridge of head shield continuous. Head shield as wide as T 3, wider than T 1. Short to moderately long setae, scattered sparsely along the lateral border of the head shield, tiny setae scattered very sparsely over the surface of the head shield.

6–8 ocelli on each side, usually 7 ( Fig. 2 ), arranged in 2 irregular rows; terminal ocellus comparatively bigger, the other ocelli approximately equal in size, overhanging the lateral margin of the head; ocelli gently bulging, moderately domed, translucent, usually darkly pigmented in eyeground.

Tömösváry’s organ ( Fig. 2 –T) moderately large, rounded, about same size as the adjoining ocelli, lying on ventral margin of head immediately proventral to the ocelli.

Maxillipede coxosternite ( Fig. 3 ) trapezoidal, dental margin moderately narrow; outboard slightly longer than inboard, median notch shallow, V shaped; dental margin with 2+2 teeth, outer tooth moderately bigger and slightly longer than the inner; porodonts stout, spine-like ( Fig. 4 ), maxillipede coxosternite with unconspicuous bulge near the base of the porodont, porodonts just posterolateral to the lateral tooth. Middle of the ventral side of the maxillipede coxosternite hunched, the lateral sloping to backside, without long setae near the dental margin, only with tiny setae very sparsely scattered over the surface of the maxillipede coxosternite.

All tergites smooth, without wrinkles, backside hunched; short, tiny setae inserted in pore scattered very sparsely over the surface; lateral marginal ridge of tergites continuous, often with 5–8 longer, thicker setae, and short to moderately long setae, scattered sparsely along the lateral borders; posterior angles of all tergites rounded, without projections; T 1 generally trapeziform, posterolateral narrower than anterolateral; posterior margin of TT 1, 2, 4, 6, 7, 9, 11, 13 straight; posterior margin of TT 3, 5, 8, 10, 12 and 15 slightly concave; posterior margin of TT 1, 3, 5 and 7 straight, TT 8 and 10 equal in width, the widest of all tergites.

All sternites generally trapeziform, short to moderately long setae scattered on the lateral borders, and 2– 5 relatively longer bristles on both anterolateral angles, a pair of longer bristles approximately symmetrical on the surface of each sternite, 1–2 longer bristles on both posterolateral angles; long bristles scattered sparsely on sternites 14 and 15, the middle part bearing a shallow rounded concavity on sternites 14 in male.

Legs strong, short to moderately long setae scattered very sparsely over the surface of coxa, trochanter, prefemur, femur, tibia of legs 1–13, setae shorter on the dorsal than the ventral side, thicker setae on tarsus; anterior side of prefemur of all legs with a shallow longitudinal furrow. Basitarsal-distitarsal articulation not well-defined on legs 1–13, without any trace on the dorsal side of tarsus of legs 1–13, but with bipartite division trace on the ventral side; a slightly evident row of setae on the ventral side of tarsus of legs 1–13, except legs 14 and 15; all segments of legs 14 and 15 shorter than those of the anterior legs, basitarsal-distitarsal articulation well-defined; distitarsus 36.7%–47.8% length of tarsus on legs 15, basitarsus 6–8 times longer than its maximum width. Tarsal claws of all legs moderately long, curved ventrad; anterior and posterior accessory claws in legs 1–13 smallish, anterior accessory claws lightly slender and sharp, posterior accessory claws moderately thicker and longer than the anterior one.

Coxal pore field set in a shallow groove. Coxal pores rounded or slightly ovate, 3–5 coxal pores arranged into a row in the female, usually 4444, otherwise 4443, 4453, 3443; coxal pores reduced to 2 in the last legs of the male (usually 4442, otherwise 4552). Size of coxal pores variable.

Female 15th sternite trapezoidal, posterior angles rounded, with transverse poster margin, a pale white heartshaped spot on the rearward of 15th sternite, only in a few specimens on the middle.

Leg pairs Ventral dorsal

C Tr P F Ti C Tr P F Ti 1 p amp am mp ap a 2 mp amp am mp ap (a)p 3–4 mp amp am mp ap ap 5 mp amp am (a)mp ap ap 6–11 mp amp am amp ap ap 12 amp amp am amp p (a)p 13 m amp amp am m amp p p 14 m amp am am m amp p 15 m amp ap am m amp

Letters in brackets indicate variable spines.

Sternite of genital segment moderately large, usually well sclerotised, long bristles scattered sparsely over the surface, lateral and posteromedian sides sloping backwards, posterior margin concave between the condyles of gonopods, except for a small, median approximately rhombic bulge, lightly sclerotised; setae scattered fairly evenly over the sternite of the genital segment, longer setae fringed along the posterior margin. Gonopod divided into three articles, the first article bearing short to moderately long setae, a fringe of longer setae along the posterior margin; 2+2 moderately small, coniform spurs ( Fig. 5 ), inner spur slightly shorter than the outer; 12–13 short to moderately long setae on the ventral side of the second article, one bristle on the dorsal side; 3–4 long setae on the ventral side of the third article, five bristles arranged into two rows on the dorsal side; distal claws tridentate, the middle is the largest, the ventral and dorsal very small ( Fig. 6 ), only two small protuberances; legs 14 and 15 moderately thicker and shorter than the anterior legs.

Male 15th sternite trapezoidal, both posterior angles rounded, poster margin straight; a round shallow concavity on the middle of the 15th sternite.

Sternite of genital segment moderately smaller than in the female, usually well sclerotised, short to moderately long setae scattered sparsely over the surface, a fringe of longer setae along the posterior margin; the posteromedial lightly concave, gonopods invisible.

Legs 15 prominently developed, and very thick; prefemur very short, of unusual crassitude, a very strong internal protuberance in dorsal view of prefemur ( Fig. 7 ), distal part of protuberance slightly concave, and curved back; tibia evidently shortened and thickened, a internal bulge on the basal of the tibia ( Fig. 8 ), 11 falciform thorns on the protuberance ( Figs. 9–10 ), forming an ellipse, distinct cluster of bristles behind the protuberance; posterior dorsal spine on the prefemur exceptionally strong, and pointing at the controlateral one; a lamina-shaped protuberance near the back of the femur, its anterior margin serrated; the other lingulate protuberance of the femur curving to the end, 6 thick and long bristles on protuberance. Longitudinal protuberance on the dorsal of the tibia, external margin slightly curved, slightly X-shaped on both sides, thick bristles on protuberance, the legs 14 also thicker than the anterior legs, but not as stout as legs 15, without protuberances.

Discussion: The new species resembles V. zapparolii sp. n., from Shanxi Province, having the same number of teeth on the dental margin of maxilliped coxosternite, the first article of the gonopod bearing 2+2 spurs and posterior angles of all tergites rounded; but it can be easily distinguished from the latter by having smallish spurs on prefemur and femur of the last pair of legs in male instead of evidently strong spurs and different leg spinulation; the spurs on the tibia are concentrated on a protuberance rather than separated as in V. zapparolii .

Figures

FIGURES 1 – 6. Validifemur pedodontus sp. n. 1, holotype, female, scale 500 μm; 2, maxilliped coxosternum, scales 500 μm; 3, ocelli and Tömösváry organ, scale 250 μm; 4, dental margin of maxillipede coxsternum, scale 250 μm; 5, female, posterior segments and gonopods, scale 500 μm; 6, female, claw of gonopods, scale 250 μm.

FIGURES 7 – 10. Validifemur pedodontus 7, male, anal legs, posterior segments and gonopods, dorsal view, scale 500 μm; 8, male, anal legs, posterior segments and gonopods, ventral view, scale 500 μm; 9, left anal leg, right view, scale 500 μm; 10, right anal leg, left view, scale 500 μm.