Neolucanus baongocae, Nguyen

Nguyen, Thai Quang, 2013, Description of a new species of the genus Neolucanus Thomson, 1862 (Coleoptera: Lucanidae) from central Vietnam, Zootaxa 3741 (3), pp. 377-384 : 378-383

Neolucanus baongocae, Nguyen , new species

Type material. Holotype: Vietnam: Lam Dong Province: ♂, Mt. Bidoup, Bidoup—Nui Ba National Park, 1550 –1623m, 15.V.2013, deposited at VNMN) Hanoi, Vietnam. Paratypes: Vietnam: Lam Dong Province: 40 specimens (37 ♂♂, 3 ♀♀), same data as holotype: 1♂, 1♀ deposited in BNHM; 1♂ deposited at CMNO; 1♂ deposited at LBC; 30 ♂ deposited at LXC; 1♂ deposited at NZUF; 1♂ deposited at NMNH; 2♂, 1♀ deposited at NQTC; 1♀ deposited at VNMN.

Holotype description ( Figs 1 , 5–8 ). ♂, total length 43.5 mm, mandible length 10.5 mm, head width 11.5 mm, prothorax width 17.0 mm, elytra length 20.5 mm, elytra width 15.5 mm. Habitus: Mandibles, head, and legs black; pronotum red on disc and posterior margins; elytra brownish yellow, black on margins; scutellum black; ventral surface black. Head: About 2 times wider than long. Dorsal surface smooth, without punctures. Surface gradually depressed distally, frontal margin strongly depressed. Canthus obtuse, completely dividing the eye. Preocular margin broad. Mentum with short, erect, reddish-yellow setae, anterior margin convex, with anterolateral angles rounded. Submentum deeply concave, rectangular. Gula smooth. Mandibles rather short, about 1.8 times longer than head; stout, with yellow setae on the basal section. Apical fork formed by an upper subapical horizontal tooth and the acute apex of the mandible; two sharp teeth at inner apical margin, a triangular subbasal tooth at the base, 5–7 small teeth between the two anterior teeth and the subbasal tooth. Antenna: With 3 apical antennomeres pubescent; antennomere 7 with width slightly greater than that of antennomere 6 and sharply pointed at tip.

Pronotum: Surface shiny and smooth; as long as and markedly wider than head; strongly convex and shiny red on disc, black at sides; front angle rather blunt, the lateral margin slightly concave at middle; hind and lateral angles obtuse, not spiniform. Elytra: Markedly wider than head and slightly narrower than pronotum; surface shiny on disc, sides nearly straight, smooth, without striations or punctures. A broad and diffuse black band at the base. Each elytron is brownish yellow; the outer margins with a wide, black band, oval shaped. Legs: Lateral margin of protibiae with two distinct teeth at distal half; the rest smooth. Mesotibiae and metatibiae straight, without teeth. All tibiae have yellow setae on surface. Male genitalia: See Fig. 8 .

Male paratypes: Body length from apex of mandible to tip of elytra: 31–47 mm. Variability: Two forms can be identified by the shape of the mandibles: 1) a large form, with body length greater than 35 mm, mandible length equal to two-thirds of the head width, and mandible with an upraised and bent inside carina near base; 2) a small form, with body length 31–35 mm, and mandibles slenderer and without upraised and bent inside carina.

8 Female paratypes ( Fig. 2 ): Body length from apex of mandibles to tip of elytra: 29–32 mm. Habitus: Mandibles, legs, and head black; pronotum reddish black on disc and black at margins. Elytra are brownish yellow with a black patch dilated at base and gradually narrowing at the apex of each elytron to make a “v” shape, black at margins. Head: Covered by punctations on dorsal surface except the middle of posterior margin; middle of head with bulbous protrusion. Frontal margin strongly concave. Canthus completely dividing the eyes. Mentum densely punctate and sparsely covered by yellow setae, rectangular but nearly square, and rounded at anterolateral angles. Submentum concave and sparsely punctate and setose. Mandible strongly incurved at base of outer margin and nearly straight at inner margin, with 2–3 small inner teeth. Antennal club with 3 apical antennomeres pubescent; antennomere 7 with width slightly greater than that of antennomere 6 and sharply pointed at tip. Pronotum: small punctures on the surface; convex at middle; anterior angle pointed, lateral angle and posterior angle are rounder; all margins smooth. Elytra: Surface shiny and smooth on disc, with the sides nearly straight, smooth, without striations or punctures; yellow with a black v-shape black patch dilated at base and gradually narrowing towards the apex. Legs: Protibia rather straight, with 2 distinct, small teeth mostly at the apical 1/3 along the lateral margin; otherwise smooth. Mesotibia and metatibia straight, without teeth.

Distribution. Central Vietnam: Lam Dong Province (Mt. Biduop, type locality).

Etymology. This species is named after my daughter, Baongoc Nguyen.

Diagnosis. Based on characteristics of the mandibles and body, Neolucanus can be partitioned into five main groups as follows: The Neolucanus fuscus group, which has long, slender mandibles, forked at the tip. This group includes: N. brochieri , N. delicatus , N. fuscus , N. inaharai , N. lehmanni , and N. sianoukei . Maes (1992) listed N. armatus (from Tam Dao) as a junior synonym of N. delicatus but N. armatus is a synonym of N. fuscus . The type locality of N. delicatus is Annam (Didier 1927), but for a long time some authors (Mizunuma & Nagai 1994, Baba 1995) reported N. delicatus from north Vietnam (Tam Dao—Vinh Phuc). This lead to confusion between N. delicatus and N. fuscus . In comparison, the mandibles of N. delicatus are slender and more curved upward than in N. fuscus . Okuda (2009) reported N. delicatus from Quang Ngai (central Vietnam). Schenk (2011) did not list N. sianoukei in this group; perhaps it is a synonym of N. fuscus . The Neolucanus sinicus group, which has short, stout mandibles with an upward and forward tooth before the apex in large males. This group includes: N. benoiti , N. chongguo , N. curvidens , N. diffusus , N. donckieri , N. doro , N. extremus , N. eugeniae , N. fiedleri , N. guizhoui , N. hagiangensis , N. iijimai , N. imitator , N. insuralis , N. latissimus , N. lemeei , N. montanus , N. nitidis , N. pallescens , N. pseudovicinus , N. quangxii , N. rufus , N. sarrauti , N. shaanxiensis , N. sinicus , N. swinhoei , N. tao , N. vicinus , and N. zebra . (Wan et al. (2007) considered N. aterrimus to be a junior synonym of N. montanus . Fujita (2010) downgraded N. robustus and N. rutilans to subspecies of N. sinicus ). The Neolucanus castanopterus group, which has short, flat mandibles without any upward or forward teeth on upper side of mandible. This group includes: N. castanopterus , N. chiangmaiensis , N. dohertyi , N. lawannorum , N. marginatus , N. oxyops , N. parryi , N. pentaphylus , N. similis , N. suzumurai , and N. svenjiae . The Neolucanus brevis group, which has short, stout, upward curved mandibles that are never forked at the tip. This group includes: N. borneensis , N. brevis , N. cingulatus , N. didieri , N. guiardi , N. laticollis , and N. punctulatus . Arrow (1949) indicated that N. latus is closest to N. brevis , differing from sides of the head: rounded in front, It is N. brevis ; but sides of the head obtusely angular in front, It is N. latus . Therefore N. latus can be assigned to the N. brevis group. The localtity of N. latus is India, Burma (Arrow, 1949) so perpaps, the putative N. latus as pictured in Fujita (2010), which was collected from Tam Dao, is instead N. similis . The Neolucanus maximus group, which has stout mandibles, a robust body and a broad canthus. Some species have two vertical teeth on upper side of each mandible. This group includes: N. angulatus , N. baladeva , N. giganteus , N. insulicola , N. maedai , N. maximus , N. okinawanus , N. perarmatus , N. protogenetivus , N. saundersi , and N. tanakai . (Fujita [2010] downgraded N. spicatus to a subspecies of N. giganteus ). Tsukawaki (2011) described a new species Neolucanus katsuraorum , very close to N. maedai ; very few characters differ between the two, and N. katsuraorum may be a synonym or subspecies of N. maedai .

I did not assign the species below to any above groups because of a lack of literature in my library: Neolucanus lividus , Neolucanus maculosus , and Neolucanus palmatus .

The female of Neolucanus baongocae can be easily distinguished from females of N. lividis , N. palmatus , and N. maculosus by the following characteristics: female of N. baongocae reddish black on disc and black at margins of pronotum, whereas body of female of N. lividus entirely black; pronotum of female of N. palmatus and N. maculosus entirely brownish black (Mizunuma & Nagai, 1994).

The new species, Neolucanus baongocae , possesses a long upward and inward carina on each mandible. It does not exhibit the characteristics of any of the above groups.

In comparing habitus with other species, the new species, Neolucanus baongocae , is closest to the medium form of Neolucanus fuscus Didier, 1926 , from Tam Dao National Park (Vinh Phuc, Vietnam). Neolucanus baongocae can be distinguished from N. fuscus by the following combination of characters:

mandibles of large males of Neolucanus baongocae proportionally shorter than those of large males of N. fuscus ; N. baongocae with an upraised carina inside the bend of male mandible

pronotum surface red with black margins (totally black in N. fuscus )

submentum strongly concave (flat in N. fuscus )

Lateral margin of pronotum slightly concave between anterior angle and lateral one (straight in N. fuscus )

Note on the natural history and habitat. The new species, N. baongocae , was found in an undisturbed forested mountain area of Bidoup—Nui Ba National Park, Lam Dong Province. Specimens were collected during the day and when walking around and at night by light traps. The elevation of the collection site was 1550–1623m. The new species was collected on dense, foggy days. The forests at collecting points are characterised by mediumsized trees and high humidity.

Figures

FIGURE 1. Neolucanus baongocae new species ♂ (Holotype) dorsal (a) and ventral (b), Bidoup Mountain, Lam Dong province, central Vietnam (scale bar = 1 cm).

FIGURE 2. Neolucanus baongocae new species ♀ (paratype), dorsal (a) and ventral (b) (scale bar = 1 cm).

FIGURE 5. Neolucanus baongocae new species (holotype) (a), N. fuscus (b): lateral view.

FIGURE 6 – 8. Neolucanus baongocae new species. 6, mentum and submentum of holotype; 7, mandibles of large male; 8, male genitalia (holotype), ventral (a), lateral (b), and dorsal (c).