Pukupuku arunachalensis sp . nov . ( Coleoptera , Scarabaeidae , Rutelinae ) from Arunachal Pradesh , India

A new species of the genus Pukupuku Muramoto, 2006 is described from the state of Arunachal Pradesh (Northeast India): Pukupuku arunachalensis sp. nov. Relevant diagnostic characters are illustrated and compared with closely related species, Pukupuku curtus (Arrow, 1919) and Pukupuku katsurai (Muramoto, 2002). The distribution of the new species is mapped.


R e s e a r c h a r t i c l e
urn:lsid:zoobank.org:pub:D7142011-F22B-48C0-987D-FD8015A0E985 mandibles and parameres are quite different in these two groups of rutelines, and Pukupuku should thus be maintained as an independent genus in agreement with Do (2013).
While working on the Rutelinae collection deposited in the collection of the Zoological Survey of India, Kolkata, six specimens of P. arunachalensis sp. nov. were studied, described, illustrated and diagnosed. The newly described species was analyzed and illustrated against each generic character proposed by Muramoto for the genus Pukupuku. The relevant diagnostic characters of head, pronotum, elytra, pygidium, legs, meso-and metasternum, abdomen and aedeagus are illustrated for both male and female type specimens.

Material and methods
The material of the new species was collected in Namdapha National Park, currently located in Changlang, district of the state of Arunachal Pradesh, India.
The aedeagus was dissected and cleaned in a KOH solution of 10% for 30 minutes. The specimens were studied using a Leica M205A stereo microscope; measurements and photographs were taken through the microscope using the proprietary software (Leica application suite, V3.8).
The type specimens were deposited in the national zoological collections of the Zoological Survey of India, Kolkata.

Diagnosis
The newly described species can be easily distinguished by its unique structure of aedeagus, shape and size of mandibles which are sharply pointed at end with a small tooth in middle at outer edge (in lateral view), and four times as long as clypeus, pronotum smooth without setae, pygidium smooth (setae absent in male, present in female). See Table 1 for detailed differential characters separating P. arunachalensis sp. nov. from P. curtus and P. katsurai.

Pukupuku curtus (Arrow, 1919)
Pukupuku katsurai (Muramoto, 2002) Shape of mandibles Sharply pointed at end, with a small tooth in middle at outer edge (in lateral view) (Fig. 5) Curved upward toothed at outer edge ( Fig. 34) Curved upward and slightly inward near apex, with a long tooth before middle of upper surface (Muramoto 2002  HEAD (Figs 3-6). Glabrous, entirely smooth without any hairs dorsally. Clypeus trapezoidal, convergent in basal half, anterior clypeal margin slightly arcuate with few short and long hairs, anterior angles rounded, surface with few scattered punctures in middle and at sides, slightly convex in middle, clypeofrontal suture nearly absent with only small carina at each side, vertex with moderately large rugopunctation. Area near each eye smooth and shining. Eye canthus spatulate, wide near end and small at base, surface smooth. Labrum straight with long hairs at margin. Mentum with a rather large rounded hollow at middle. Mandibles fl at and broad at base, sharply pointed at end with a small tooth in middle (in lateral view), almost four times as long as length of clypeus. PRONOTUM (Fig. 7). Convex, 1.9 times as wide as long, widest before middle, without any hairs or setae on dorsal surface, with rather small but indistinct punctures in middle, laterally smooth, narrowly marginate except near base, base distinctly lobed before scutellum, anterior, lateral, and hind angles rounded. SCUTELLAR PLATE (Fig. 8). Triangular, base carinate, lateral sides curved, apex rounded, densely punctate on sides with a line of punctures.
ELYTRA (Figs 9-10). Convex, almost as wide as long, widest at middle; rather densely and closely punctate near sutural margins from base to apex, rather sparsely and fi nely punctate in middle and at lateral sides, entirely yellow with a brown spot behind scutellar apex near sutural margin, brown pit at base in middle, two transverse bands, one large and one small, at lateral side on humeral umbone (in lateral view), apex with a large brown band on each elytron. European Journal of Taxonomy 257: 1-11 (2017) LEGS (Figs 11-15). Protibae tridentate, claws not cleft. Meso-and metatibiae unidentate, outer claw with a ventral tooth respectively, 4 th tarsomere of both meso-and metatibiae with a single acuminate ventroapical process with a pair of fi ne long setae. PYGIDIUM (Fig. 16). Triangular, thrice as broad as long, without hairs.
VENTER (Figs 17-19). Ventral surface of thorax and metasternum densely hairy. Prosternum with a small process in middle of posterior margin, posterior face of it fl at. Meso-and metasternal processes absent. Abdominal sternites brown black, not abbreviated, smooth without hairs, segments curved in shape.
COLOUR. Yellow with brown marking on lateral sides of elytra.

Collecting circumstances
Collected at night by light after dusk.

Discussion
The genus Pukupuku was recently established by Muramoto, including only two species: type of the genus P. curtus and P. katsurai. Pukupuku arunachalensis sp. nov. is the third species described in the genus. Muramoto (2006) mentioned in her paper, while proposing the genus that she did not examine the female, but predicted the female to have unidentate meso-and metatibiae and a ventroapical process of the 4 th metatarsomere with a pair of fi ne and long hairs. On examining the females of the newly described species in detail (Figs 25-33), it can be concluded that the females also share the characters proposed for the genus.
So far, there are only two ruteline species with such remarkably hypertrophied male mandibles known from India: P. arunachalensis sp. nov. and Didrepanephorus bifalcifer Wood-Mason, 1878 reported from Assam (Arrow 1917). Didrepanephorus bifalcifer differs from P. arunachalensis in having asymmetrical parameres and mandibular horns lacking a tooth in the middle. Moreover, D. bifalcifer is densely covered by short, semi-erect hairs dorsally.