Lithobius (Ezembius) maqinensis, Qiao, Qin, Ma & Zhang, 2019

Penghai Qiao, Wen Qin, Huiqin Ma & Tongzuo Zhang, 2019, Two new species of lithobiid centipedes and the first record of Lamyctes africanus Porath (Chilopoda: Lithobiomorpha) in China, Journal of Natural History 53 (15), pp. 897-921 : 905-908

Lithobius (Ezembius) maqinensis sp. nov.

( Figure 3 )

Type locality

Maqin Countyı located in south-eastern Qinghai Provinceı with plateau mountain habitat; 34.44544°Nı 100.26906°Eı altitude 3744 mı 7 October 2011ı collected by Weiping Li.

Material examined

♀ holotype ( MQ 4)ı 2 ♀ ( MQ 6ı MQ 7)ı 7 Ƌ ( MQ 1ı MQ3ı MQ5ı MQ8ı MQ9ı MQ10ı MQ 12) paratypes.

Diagnosis

Medium- to large-sized Lithobiidae (body length 13.1 – 14.6 mm). Antennal articles fixed at 20. Ocelli numerousı 1 + 4ı 3ı 2 or 1 + 4ı 4ı 2 or 1 + 5ı 4ı 2. Forcipular coxosternite with 2 + 2 teeth. Porodont situated laterally and ventrally to the forcipular coxosternal teeth. Tergites without posterior triangular projections. Tarsi of legs 1 – 13 undividedı legs 14 – 15 divided. Female gonopods with 2 spurs and simple claw with tiny triangular protuberance on the ventral basal side. Male gonopods single and always wholly concealed.

Remarks

Lithobius (Ezembius) maqinensis sp. nov. is morphologically close to L. (E.) giganteus Sseliwanoffı but can be readily distinguished by the following characters: 10 – 12 ocelli arranged in 3 rows (vs 6 – 10 arranged in 2 or 3 rows in L. (E.) giganteus )ı tarsal articulation not well defined on legs 1 – 13 (vs well defined)ı and apical claw of female gonopods simple with a small subtriangular tooth on the ventral side.

Description

Based on holotype (♀)ı body length 13.1 mm; cephalic plate width 1.8 mmı length 1.9 mm.

Colour. Body yellow-brown with reddish hue. Dorsal plates with a median longitudinal dark stripeı venter coloured similarly to body. Antennae brown. Legs yellow. Distal part of forcipules and coxosternal teeth dark brown.

Antennae. Antennae composed of 20 + 20 articlesı antennal length 3.0 times width of head shieldı extending to anterior part of T3ı the first article longer than wideı the second slightly longer than wideı the third to seventh wider than longı then elongateı the ultimate about 2.5 times the length of the penultimate article.

Cephalic plate. ( Figure 3 (a)) Sub-cordateı smooth and glossyı nearly the same width as length. Four pairs of setae anterior to transverse suture with bilateral symmetry. Frontal marginal ridge with shallow anterior median furrow. Posterior margin slightly concave. Lateral margin discontinuousı broken about one-third the distance forward from the caudal edge.

Ocelli. ( Figure 3 (b)) 1 + 5ı 4ı 3 arranged in 3 rowsı the most posterior ocellus largestı the ocelli of the bottom row small.

Tömösváry ’ s organ. Almost the same size as adjacent ocelliı well removed from the eye-patch area.

Forcipular coxosternite. ( Figure 3 (c)) Sub-trapezoidal; dental margin narrowı with 2 + 2 teethı setiform porodonts on small knobs; no lateral shoulders; median diastema cut deepı V-shaped; some scattered setae on the ventral side of coxosternite.

Tergites. ( Figure 3 (a)) smoothı never rugose; T1 posterolaterally narrower than anterolaterallyı trapeziformı narrower than T3 and the cephalic capsuleı T3 almost the same width as the cephalic capsule; posterior margin of TT 1ı 3ı 5ı 10ı 12ı 14 concaveı posterior margin of TT 7ı 8 straightı posterior marginal ridge of TT 1ı 3ı 5 continuous; posterior angles of all dorsal plates rounded without triangular projections; lateral marginal ridge of all tergites continuous; more setae on anterior and posterior angles of each tergite.

Sternites. Smoothı trapeziformı posteriorly narrow; 2 – 3 small setae on the lateral bordersı 1 – 2 comparatively long setae scattered sparsely on anterior and posterior lateral margin of each sternite. SS 11 – 15 more densely setose on anterior and posterior borders; posterior margins straight.

Legs. Legs 1 – 13 with unipartite tarsiı tarsi of legs 14 and 15 divided into 2 tarsomeres. Leg pairs 14 and 15 longer and thicker than 1 – 13. Leg 15 longest of allı tarsus 1 about 2.6 times longer than wideı tarsus 2 about 67% length of tarsus 1 on leg 15. Abundant glandular pores on ventral surfaces of femurı tibia and tarsus of legs 14 and 15. All legs with tarsal clawsı fairly longı curved ventrally. Legs 1 – 13 terminate in primary claws with anterior and posterior accessory spinesı anterior accessory spines long and slenderı about 0.33 times the length of principal clawı posterior one slightly strongerı about 0.3 times the length of principal claw. Anal legs with the tarsal claw singleı penultimate legs with the tarsal claw armed at base with posterior accessory spines. Legs ’ plectrotaxy: as in Table 2 .

Coxal pores. ( Figure 3 (d)) Formula 6666ı round and uni-seriateı the most proximal pore on 15th coxae minute. Coxal pore field set in a relatively shallow grooveı the fringe of coxal pore field slightly distinct.

Female posterior segment. Posterior margin of genital sternite deeply concave between the condyles of gonopodsı except for a smallı median approximately fingerlike bulge. Female gonopod ( Figure 3 (d)): first article fairly broadı bearing about 24 long setae arranged in 4 irregular rows; 2 + 2 moderately smallı coniform spursı inner spur smallerı separated from one another by their own diameter at base. Second article with 10 medium to long setae. Third article with 4 long setae on its ventral surface. Terminal claw unidentateı curved with a small triangular protuberance on ventral side.

Male posterior segment. Male first genital sternite undivided longitudinallyı well chitinised. Posterior margin quite deeply concave between the gonopodsı no bulge medially; 32 short to medium setae scattered sparsely over its surface and at lateral margins ( Figure 3 (e)). Male gonopod: smallı undividedı oblique apicallyı with 2 setae ( Figure 3 (e)).

Variation

Body length 13.10 – 14.60 mm; ocelli 9 – 11ı 1 + 4ı 3ı 1 or 1 + 4ı 3ı 2 or 1 + 5ı 4ı 2; coxal pores 4445ı 5466ı 6666 in femaleı 4444ı 4555ı 5554ı 5664ı 5665 in maleı ovate to roundı in each serious decreasing in size proximal as usual.

Habitat

Collected under stones in alpine meadows composed mainly of Gramineae and Cyperaceae .

Etymology

The new species is named from the type locality.

Figures

Figure 3. Lithobius (Ezembius) maqinensis sp. nov.ı (a–dı f) holotypeı female: (a) habitusı dorsal viewı scale 1 mm; (b) ocelli and Tömösváry’s organ (To)ı lateral viewı scale 250 µm; (c) forcipular segmentı ventral viewı scale 500 µm; (d) posterior segments and gonopodsı ventral viewı scale 500 µm; (f) right gonopodı dorsal-lateral viewı scale 250 µm; (e) paratypeı male: male gonopodı ventral viewı scale 500 µm.