Two new species of Yaginumaella (Araneae, Salticidae) from Wuling Mountain, China

The present paper deals with two new species, Yaginumaella pulchella sp. nov. and Yaginumaella hubeiensis sp. nov. Distributional data, as well as illustrations of body and copulatory organs, are provided. Descriptions of their morphology are given. The differences between the new species and their related taxa are discussed.


Material and methods
All specimens were kept in 75% ethanol, examined, measured and drawn with an Olympus SZX16 stereomicroscope and an Olympus BX53 compound microscope. Photos were taken with a digital camera Canon PowerShot G12 mounted on an Olympus SZX16. Compound focus images were generated using Helicon Focus software v. 3.10.
Leg measurements are given as total length (femur, patella plus tibia, metatarsus, tarsus). Specimens are deposited at the College of Life Sciences, Hunan Normal University (HNU).

Etymology
The specifi c name comes from the Latin adjetive pulchellus, -a, -um (diminutive of pulcher), meaning "beautiful little", and referring to the distinct marking on the dorsal side of the abdomen.

Description
Male (holotype) Total length 6.08 mm. Cephalothorax 3.01 × 2.04 mm. Abdomen 2.08 l × 1.91 mm. Eye sizes and interdistances: AME 0.67 mm, ALE 0.37 mm, PLE 0.39 mm, AER 2.07 mm, PER 1.95 mm, EFL 1.41 mm. Carapace brown to orange in color followed by a pair of longitudinal white hairs band on lateral sides; median ocular area provided with a round patch of white hairs. Basal area of each eye, anterior, and lateral margins of ocular area black with black hairs. Thoracic region fl at. Fovea short and longitudinal. Chelicerae yellowish-brown, two pro-marginal and one retro-marginal tooth. Endites longer than wide, yellowish-brown. Labium ligulate with thick hairs, terminal area lightly colored. Sternum almost oval, covered with yellow hairs. Legs yellowish-brown, terminal areas darker in I and II. Measurements of legs: I 6.70 mm (2.10 mm, 2.75 mm, 1.15 mm, 0.70 mm), II 5.61 mm (1.71 mm, 2.18 mm, 1.02 mm, 0.70 mm), III 6.37 mm (2.04 mm, 2.20 mm, 1.31 mm, 0.82 mm), IV 6.54 mm (2.12 mm, 2.30 mm, 1.39 mm, 0.83 mm). Leg formula: 1432. Abdomen oval, yellowish-green with lighter yellowish central area, followed by the longitudinal greenish band on lateral areas and transversally in the posterior,

Differential diagnosis
The new species resembles Y. pulchella sp. nov., but can be distinguished by: (1)

Etymology
The specifi c name comes from the type locality.

Description
Male (holotype) Total length 6.98 mm. Cephalothorax 3.28 × 2.44 mm. Abdomen 3.49 × 2.03 mm. Eye sizes and interdistances: AME 0.63 mm, ALE 0.34 mm, PLE 0.18 mm. AER 2.06 mm, PER 1.82 mm, EFL 1.38 mm. Carapace reddish brown, with three longitudinal yellowish-brown stripes on the median and two on the lateral areas (extending from the posterior margin of the ocular area to posterior margin of carapace). Lateral areas densely covered with longitudinal white hairs strips. Central area lightly colored. The base of each eye, anterior and lateral margins of ocular area black with black hairs. Thoracic region fl at, fovea longitudinal, shallow, and indistinct. Cervical and radial grooves distinct. Sternum oval, covered with short brown hairs, central area bulged. Chelicerae yellowish-brown, two pro-marginal and one retro-marginal tooth. Legs yellowish-brown with annuli, terminal area darker. Measurements of legs: I 7.35 mm (2.52 mm, 2.82 mm, 1.28 mm, 0.73 mm), II 5.87 mm (2.04 mm, 2.43 mm, 0.89 mm, 0.51 mm), III 6.03 mm (2.26 mm, 2.32 mm, 0.85 mm, 0.60 mm), IV 6.96 mm (2.30 mm, 2.42 mm, 1.54 mm, 0.70 mm). Leg formula: 1432. Abdomen oval, dark brown with lighter yellowish central area with inclined white stripes, followed by the longitudinal dark band on lateral areas and transversally in the posterior, dorsum scattered with lots of white and grayish-black patches, lateral area two pairs of muscular impressions distinct. Venter white, scattered with black patches, median area with one longitudinal dark brown stripe. Palp (Figs 4B-C, 5A-B): tibia thick, terminal part of the tibial apophysis straight in retrolateral view. Palpal bulbus slightly wider anteriorly, with a membranous structure at the center, posterior end with a deep depression. Embolus bow-shaped, much longer than the palpal bulbus, originated from the position of 7:00 o'clock. Sperm ducts robust. Variation: total length 5.97-6.98 mm (n = 10).

Discussion
The genus Yaginumaella is placed under the subtribe Plexippina (Maddison, 2015) of subfamily Salticinae (Maddison, 2015) (Maddison 2015). Currently, a total of 46 species have been described mainly from subtropical Bhutan, China, India, Japan, Korea, Myanmar, Nepal, and Russia (World Spider Catalog 2018), and Ptocasius (Simon, 1885) only contains 13 species described from China, India, Kazakhstan, Myanmar, Singapore, Sri Lanka, and Vietnam (World Spider Catalog 2018). Most of the taxonomists have reported that Yaginumaella is closely similar to, and may well be synonymous with, Ptocasius (Żabka 1985;Song 1991;Hu 2001;Sunil 2013;Logunov & Jäger 2015), in particular, the characteristics of the female are so close that it is diffi cult to distinguish. Even many scholars think it should be merged. So far, as there is no particular consensus, they are considered two separate genera. In future, many species will need to be transferred depending on taxonomic revisions. But, based on the characteristics of specimens checked by the authors, together with those illustrated in literature, we think the two genera can be diagnosed as: (1) thoracic region steep in Ptocasius vs fl at in Yaginumaella; (2) carapace with a transverse stripe in Ptocasius vs a pair of longitudinal dark bands extending from back of ALE to retromargin in Yaginumaella; (3) abdomen with transverse stripes in Ptocasius vs usually with longitudinal stripes in Yaginumaella; (4) embolus two times longer than palpal bulbus, originating from the right margin of the palpal bulbus, and palpal bulbus without posterior lobe in Ptocasius vs as long as palpal bulbus, originating from the left margin of the palpal bulbus, and palpal bulbus with posterior lobe in Yaginumaella. Because of this, the two new species we describe fi t the characteristics of Yaginumaella.