Acroterius brevis, Irfan & Bashir & Peng, 2021

Irfan, Muhammad, Bashir, Shahida & Peng, Xianjin, 2021, Acroterius gen. nov. (Araneae: Linyphiidae: Linyphiinae) with twelve new species from Yunnan, China, European Journal of Taxonomy 743, pp. 1-53 : 8-14

Acroterius brevis gen. et sp. nov.

urn:lsid:zoobank.org:act:F041D21F-15E7-4C22-895A-4AF2565105D4

Figs 5–9 , 38

Differential diagnosis

The new species resembles A. camur gen. et sp. nov. in distal arm of paracymbium with three projection ( Figs 6B , 7B , 10B , 11B ), but can be distinguished from A. camur gen. et sp. nov. and all other Acroterius gen. nov. species by the ventral view, radical apophysis triangular and reaches to base of embolus ( Figs 6D , 7A ), but thumb-shaped and extends above embolus in A. camur gen. et sp. nov. ( Figs 10D 12A ). Spermathecae L-shaped, present near posterior median plate ( Fig. 8A–B ), but hook-shaped and separated by one and half-length of spermathecae in A. camur gen. et sp. nov. ( Fig. 13A–B ). Parmula 0.47 long ( Fig. 8D ), but 0.21 long in A. camur gen. et sp. nov. ( Fig. 13D ).

Etymology

The species name comes from the Latin adjective ‘ brevis ’ meaning ‘short’, referring to the short radical apophysis in male palp.

Type material

Holotype CHINA • ♂; Yunnan Province, Fugong County, Lumadeng Township, Yaping Village , Shibali ; 27.16515° N, 98.77975° E; alt. 2527 m; 1 May 2004; Guang-xu Peng leg.; HNU-20040501–1.

Paratypes (2 ♀♀)

CHINA • 1 ♀, same collection data as for holotype; HNU-20040501–2 • 1 ♀; Yunnan Province, Fugong County, Yaping, 3 km to Shibali; 27.1775° N, 98.7550° E; alt. 2527 m; 4 May 2004; Heng-mei Yan and Guang-xu Peng leg.; HNU-20040504 .

Description

Male (holotype)

MEASUREMENTS AND COLOUR. Total length: 2.66. Carapace 1.40 long, 1.14 wide, cephalothorax dark brown; clypeus 0.56 high ( Fig. 9A–B ); abdomen 2.03 long, 1.60 wide. Eye sizes and interdistances: AME 0.08, ALE 0.09, PME 0.08, PLE 0.07, AME–AME 0.03, PME–PME 0.06, AME–ALE 0.08, PME–PLE 0.07, ALE–ALE 0.45, PLE–PLE 0.49.

CHELICERAE. With four promarginal and four retromarginal teeth; proximal teeth of reteromargin much longer than distal one.

LENGTH OF LEGS. I = 4.89 (1.63, 1.47, 1.16, 0.63), II = 3.74 (1.11, 1.31, 0.83, 0.49), III = 3.17 (0.88, 0.96, 0.82, 0.51), IV = 4.35 (1.26, 1.26, 1.17, 0.66). Leg formula I–IV–II–III.

PALP ( Figs 6A–D , 7A–B ). Paracymbium highly sclerotized, distal arm with three projections; lateral projection large, curved, beak-shaped; median projection tongue-shaped; ventral projection sclerotized, thumb-shaped with blunt end, overlapping subtegulum ( Figs 6B , 7B ); distal suprategular apophysis long, robust with distal pointed end (in ventral view) ( Figs 6B–D , 7B ). Radix with small radical apophysis

with pointed end ( Figs 6A–D , 7A–B ); radical apophysis somewhat triangular with blunt end ( Figs 6A , 7A ). Embolus stout, short with pointed end ( Figs 6A–D , 7A–B ).

Female (HNU-20040501–2, Fig. 9C–D )

MEASUREMENTS AND COLOUR. Total length: 2.97. Carapace 0.94 long, 0.83 wide, cephalothorax dark brown; fovea, cervical and radial grooves distinct; clypeus 0.27 high ( Fig. 9C–D ); abdomen 1.8 long, 1.05 wide. Eye sizes and interdistances: AME 0.06, ALE 0.09, PME 0.08, PLE 0.07, AME–AME 0.06, PME–PME 0.07, AME–ALE 0.07, PME–PLE 0.07, ALE–ALE 0.41, PLE–PLE 0.45, ALE–PLE contiguous.

LENGTH OF LEGS. I = 4.40 (1.23, 1.39, 1.03, 0.75), II = 3.92 (1.15, 1.28, 0.91, 0.58), III = 3.07 (0.94, 0.93, 0.71, 0.49), IV = 4.11 (1.13, 1.35, 0.96, 0.67). Leg formula I–IV–II–III. Tm I and Tm IV present. Patella of each leg with two spines. Tibial dorsal spine formula: 2–2–2–2.

EPIGYNE. Parmula 0.47 long, 0.41 wide at base ( Fig. 8A–C ); the posterior margin of the anterior wall of epigynal plate with a beak-shaped projection on each side ( Fig. 8A–C ). Spermathecae slender, L-shaped ( Fig. 8D ).

Distribution

China (Yunnan Province, Fig. 38 ).

Figures

Fig. 5. Acroterius brevis gen. et sp. nov., ♂, holotype (HNU-20040501–1). A. Chelicera, dorsal view. B. Chelicera, ventral view.

Fig. 6. Acroterius brevis gen. et sp. nov., ♂, holotype (HNU-20040501–1), palp. A. Prolateral view. B. Retrolateral view. C. Dorsal view. D. Ventral view.

Fig. 7. Acroterius brevis gen. et sp. nov., ♂, holotype (HNU-20040501–1), palp. A. Prolateral view. B. Retrolateral view.

Fig. 8. Acroterius brevis gen. et sp. nov., ♀, paratype (HNU-20040501–2). A–B. Epigyne, ventral view. C. Epigyne, lateral view. D. Vulva, dorsal view.

Fig. 9. Acroterius brevis gen. et sp. nov. A–B. ♂, holotype (HNU-20040501–1). C–D. ♀, paratype (HNU-20040501–2). A, C. Habitus, dorsal view. B, D. Habitus, ventral view.

Fig. 38. Map indicating the type localities of Acroterius absentus sp. nov. (), A. brevis sp. nov. (), A. camur sp. nov. (), A. hamatus sp. nov. (), A. inversus sp. nov. () and A. latus sp. nov. ().

Fig. 10. Acroterius camur gen. et sp. nov., ♂, holotype (HNU-DHK–2002–038), palp. A. Prolateral view. B. Retrolateral view. C. Dorsal view. D. Ventral view.

Fig. 11. Acroterius camur gen. et sp. nov., ♂, holotype (HNU-DHK–2002–038). A–B. Embolic division, ventral view. C. Embolic division, prolateral view. D. Embolic division, dorsal view.

Fig. 12. Acroterius camur gen. et sp. nov., ♂, holotype (HNU-DHK–2002–038), palp. A. Prolateral view. B. Retrolateral view.

Fig. 13. Acroterius camur gen. et sp. nov., ♀, paratype (HNU-DHK–2002–038). A–B. Epigyne, ventral view. C. Epigyne, lateral view. D. Vulva, dorsal view.