Scolopocryptops hoanglieni n. sp.

Figs 11–13

Locus typicus. Hoang Lien NP, Lao Cai Province, Northwestern Vietnam.

Material. LAO CAI Province, Hoang Lien NP, natural forest: Holotype (SVR.HL.002), 22.35063°N 103.77477°E, 1927 m a.s.l., 16.09.2020, col. Do T. Thinh; 2 Paratypes (SVR.HL.007, SVR.HL.008), 22.34563°N 103.77552°E, 2004 m a.s.l., 16.09.2020, col. Le X. Son; 1 spm (HL. 133 in VAST), 22.34603°N 103.7777°E, 2000 m a.s.l., 29.11.2018, col. Nguyen Duc Hung; Bat Xat NR, mixed bamboo forest, 22.6158°N 103.6359°E, 1686 m a.s.l., 1 spm (BX.026), 18.10.2018, col. Sung A. De.

Diagnosis. 2 basal antennal articles virtually lacking setae; cephalic plate marginate laterally; tergites lacking paramedian sutures, tergites 6–20 with a well-developed “drop-like” longitudinal median depression, ultimate tergite with complete lateral margination; LBS 7 lacks spiracles; ultimate legs not setose, ultimate prefemur with two typical (ventral and dorso-medial) spinous processes.

Description of the adult holotype SVR.HL.002.

Body length 35.3 mm, the width of LBS 10 ca 2.7 mm.

Antennae (Figs 11 AB) composed of 17 antennomeres of them 2 basal ones not setose, following articles densely covered by minute setae.

Cephalic plate (Fig. 11A) as long as wide, sparsely punctuate and marginate laterally, posterior margination absent.

Forcipular coxosternite (Fig. 11B): coxosternite and basal part of trochanteroprefemora coarsely and sparsely punctate. Coxosternite with a median suture which reaches its middle, some transverse sutures cross the median one in anterior third of coxosternite. Strongly sclerotised anterior margin of coxosternite definitely divided by a median diastema into two standard very low lobes; process of trochanteroprefemur small with a distinct basal suture; tarsungulum long, pointed.

Tergites lacking paramedian sutures, sparsely punctuate; anterior margin of tergite 1 covered by cephalic plate. Lateral margination incomplete on tergites 4–22 (Figs 11 CD, 13B), only tergite 23 marginate completely (Figs 12 BC). Tergites 6–20 with a long (quasi-complete) “drop-like” longitudinal median depression which expanded to tergal posterior end (Figs 11 CD, 13B) and is bordered by paramedian keels. Tergite 23 (Fig. 12B) nearly as long as wide, its posterior margin much convex in the middle.

Sternites lacking paramedian sutures, trapeziform, with many transverse / oblique sutures (Figs 11B, 12A–D). Sternite 23 (Fig. 12D) trapeziform, its posterior margin slightly concave.

Coxopleuron (Figs 12 CD) densely covered by irregularly located pores; coxopleural process pointed and long, extended over the posterior margin of tergite 23.

Legs (Figs 11D, 12A–C) 1–21 with 1 tarsal spur; 1–19 with two tibial spurs, 20–21 with 1 tibial spur; leg 1–22 with two pretarsal accessory spines.

Ultimate legs (Fig. 12E) not setose; prefemur with two spinous processes—very large ventral one and much smaller dorso-medial one, both disposed nearly at prefemur’s middle.

Variability. Incomplete lateral margination is from tergite 2 in specimen SVR.HL.007 and longitudinal median depression is present on tergite 2-22 in specimens SVR.HL.008 and BX.026.

Etymology. Named after Hoang Lien NP—the type locality of this species.

Remarks. S. hoanglieni has a much thinner body than its congeners. The new species definitely differs from S. rubiginosus by the absence (vs. presence) of tergal paramedian sutures and from S. capillipedatus by not setose ultimate legs (vs. densely setose ultimate both tibia and tarsus). The new species is relatively similar to S. spinicaudus in the absence of tergal paramedian sutures and not setose ultimate legs, but is easily distinguished from the latter by tergites with a very characteristic longitudinal depression (Fig. 11C) which character seems to be unique, at least within Scolopocryptopinae .