Rhysida aspinosa, BALAN & SURESHAN, 2017

RHYSIDA ASPINOSA BALAN & SURESHAN, 2017

( FIG. 13)

Rhysida aspinosus Balan & Sureshan, 2017: 112–113 , figs 1, 2.

Diagnosis: Twenty antennal articles. Coxosternal tooth-plates with 5 + 5 teeth. Coxopleural process relatively short, with two apical spines, lacking subapical, dorsal and lateral spines. Ultimate leg prefemur with VL1 only or spines lacking completely.

Material

CES 091308 , Achankovil Reserve Forest, Pathanamthitta district , Kerala ; CES07159 , Neyyar Wildlife Sanctuary, Thiruvananthapuram district , Kerala ; CES091079 , Rockwood Estate, Shendurney Wildlife Sanctuary, Kollam district , Kerala ; CES101451 , Periyar Tiger Reserve , Kerala, India ; collected by Jahnavi Joshi in July 2008 –2009. Locality coordinates in the Supporting Information ( Table S1) .

Description: Length ≤ 45 mm. Twenty antennal articles, basal three articles glabrous dorsally and ventrally ( Fig. 13A). Cephalic plate smooth. Longitudinal median furrow on anterior 10% of cephalic plate. Cephalic plate and T1 brown–red, the following tergites brown with green–red pigmentation, legs pale yellow. Forcipular coxosternal tooth-plates with five teeth; teeth are separated into two groups, the outer two teeth and inner three; innermost is the smallest and sometimes fused, base of tooth-plates defined by oblique sutures diverging at 110° ( Fig. 13B). Trochanteroprefemoral process bearing two apical and two lateral teeth. Tergites with paramedian sutures complete from TT5. Tergites not marginated except tergite of ultimate leg-bearing segment. Tergites smooth ( Fig. 13I). Paramedian sutures 5% length of sternites ( Fig. 13J). Tergite of ultimate leg-bearing segment 1.5 times wider than long, with parallel lateral margins, pointed apex ( Fig. 13C). Sternite of ultimate leg-bearing segment slightly wider than long; lateral margins convex, moderately convergent posteriorly; posterior margins concave with an angle of 160° ( Fig. 13D). Coxopleuron 1.4 times the length of sternite of ultimate leg-bearing segment; coxopleural process with two apical spines. Pores dense, with pore-field terminating distinctly beneath dorsal margin of coxopleuron; non-porose area on coxopleural process narrow, short ( Fig. 13D, F). Ultimate legs long, with prefemur ≤ 4.5 mm, femur ≤ 4.5 mm and tibia ≤ 3.5 mm, tarsus 1 ≤ 3 mm and tarsus 2 ≤ 1.5 mm; prefemur with VL1 ( Fig. 13G, H), except in one individual with VL1, VM1. Legs 1–8 with two tarsal spurs, legs 19–20 with one. Legs 1–3 with one tibial spur. Leg 1 with femoral spur.

Distribution: This species is found across the Shencottah Gap, in low- and mid-elevation forests in the southern Western Ghats. It has an overlapping distribution south of the Shenkottah Gap with R. pazhuthara The type locality of R. aspinosa is Thattekad Wildlife Sanctuary, Kerala ( Balan & Sureshan, 2017), which is further (~ 100 km Periyar Tiger Reserve) north of the localities from which we report it, making it a widely distributed species in the southern Western Ghats. Specimens collected from the type locality of R. aspinosus are placed within R. trispinosa in the molecular phylogeny ( Fig. 3).

Remarks: Genetic variation within COI (corrected p -distance) in this species was 12%. In both GMYC and mPTP, it was considered as a distinct species ( Fig. 3). Morphologically, R. aspinosa can be distinguished from the three other species in the R. immarginata clade in the southern Western Ghats by the presence of only the two apical spines on the coxopleural process and prefemoral spines at most represented by VL1 only. It can be distinguished clearly morphologically from another sympatric species from the R. longipes clade, R. pazhuthara , because R. aspinosa has 20 antennal articles vs. R. pazhuthara having 18, and the ultimate leg prefemora of R. aspinosa having only VL1 spines, whereas R. pazhuthara has VL3, VM3 and DM3.