Plonaphacarus lanceolatus, Liu, Dong, Wu, Donghui & Chen, Jun, 2011

Liu, Dong, Wu, Donghui & Chen, Jun, 2011, Review of Plonaphacarus (Acari: Oribatida: Steganacaridae), with descriptions of eight new species from China, Zootaxa 2739, pp. 1-26 : 15

Plonaphacarus lanceolatus sp. nov.

( Figs. 41–49 )

Material examined. Holotype: adult (in alcohol, W-89-52), China: Fujian Province, Wuyi Mt. (27°45'23.97"N, 118° 2'7.11"E), Tianyou, from litter under bamboo and arbor forest, 25 Apr., 1989, leg. Hui-Fu Wang. Paratypes: ten adults (in alcohol, W-89-52), same data as holotype; five adults (in alcohol, W-89-56), same data as holotype.

Etymology. The new specific name “ lanceolatus ” is from Latin, and refers to the shape of sensilli.

Measurements: Holotype: Prodorsum: length 330, width 215, height 108, setae: ss 120, ro 30, in 170, le 35, distance between setae: ro -ro 35, in -in 80, le -le 140; notogaster: length 660, width 458, height 435; setae: c1 170, c2 136, c3 155, c p 135, d1 140, d2 136, e1 155, e2 140, h1 195, h2 155, h3 125, ps1 195, ps2 151, ps3 120, ps4 105; distance between setae: c1-d1 182, d1-e1 220, e1-h1 150, h1-ps1 105; ventral region: ad1 120, ad2 135, ad3 55, an1 75, an2 75; genitoaggenital plate 220×160, anoadanal plate 265×120. Paratypes: Prodorsum: length 274–325, width 192–240, height 103–125; notogaster: length 535–710, width 345–500, height 337–520.

Colour grey-yellowish. Surface of body covered with small concavities.

Prodorsum with two distinct dorsal carinae; lateral carinae strong and long, extend beyond sinus and reach end of rostrum; dorsal region longer than lateral region; posterior furrows present; sensilli long with narrow pedicel and lanciform head, covered with small spines; interlamellar setae long, robust, erect, covered with small spines; lamellar and rostral setae spiniform, thin, short, rough and semi-erect; exobothridial setae vestigial; comparative length: in>ss> le>ro.

Notogaster with 15 pairs of setae, relatively long (c1 <c1-d1), robust, covered with small spines in distal half, setae h1 and ps1 longest, setae ps4 shortest; setae c1-3 slightly remote from anterior border, setae c2 more so than c1 and c3; vestigial setae f1 situated at level of setae h1; two pairs of lyrifissures ia and im present.

Nine pairs of genital setae present, arranged in two rows with formula: 7(4+3): 2; one pair of aggenital setae present; anoadanal plates each with five well-developed and rough setae, setae ad2 longest, setae ad3 shortest, shorter than anal setae.

Setae h of mentum vestigial; chaetotaxy of legs (without tarsi): I: 1-4-2(2)-5(1); II: 1-3-2(1)-3(1), III: 2-2-1(1)- 2(1), IV: 2-1-1-2(1); v’’ / v’ (femora I)=2.2; setae d on femora I remote from distal end; setae a’’ on tarsi I curved distally; setae a’’ and setae ft’’ on tarsi II straight distally; setae s on tarsi I absent; setae s on tarsi II and setae s and pv’ on tarsi IV present; setae l’ on genua IV reduced; setae d on tibiae IV long, independent of solenidions; all legs monodactylous.

Distribution. Known only from type locality.

Remark. This new species is similar to P. is h ik a w a i ( Aoki, 1980) and P. kugohi ( Aoki, 1959) but differs by following combined characters: prodorsum with two distinct dorsal carinae; lateral carinae strong and long, extend beyond sinus and reach end of rostrum; sensilli long with narrow pedicel and lanciform head, covered with small spines; lamellar setae longer than rostral setae; exobothridial setae vestigial; setae h of mentum vestigial; genital setae with formula: 7(4+3): 2; setae d on femora I remote from distal end. This new species is also similar to P. bicarinatus sp. nov., and the differences between them can be seen from the remark of P. bicarinatus .

Figures

FIGURES 41 – 49. Plonaphacarus lanceolatus sp. nov.: 41, lateral view of body (legs removed); 42, prodorsum, dorsal view; 43, prodorsum, dorso-lateral view; 44, mentum of infracapitulum; 45, right side of ventral plate; 46 – 49, trochanter, femur, genu and tibia: 46, leg I; 47, leg II; 48, leg III; 49, leg IV. Scale bars = 100 μm.