Peltonotus malayensis Arrow

(Figs. 6–7, 15, 22, 30–31, 43a–c, 55, 65)

Peltonotus malayensis Arrow 1910: 155–156 . Lectotype female at BMNH with label data: a) "Type" (round label with red border, typeface), b) "Bornéo Occ. Pontianak 1903" (typeface), c) "ex Oberthur Coll. 1908–134." (typeface), d) " Peltonotus malayensis, Arrow type ♀ " (handwritten), e) " Peltonotus malayensis Arrow ♀ Lectotype " (our red lectotype label). One paralectotype at MNHN with label data: a) “Bornéo Oc., Riv. Sintang, F. Buffat 1905” (typeface), b” Peltonotus malayensis Arrow co­type ♀ ” (handwritten), c) “ G. J. Arrow vidit 1910” (typeface), d) “Museum Paris ex. Coll. R. Oberthur ” (typeface, yellow label), e) our paralectotype label. One additional paralectotype from MNHN is conspecific with P. gracilipodus and has the following label data: a) “ Sumatra, Siboga, III.1903 ” (typeface), b) Peltonotus malayensis Arrow co­type ♀ ” (handwritten), c) “ G. J. Arrow vidit 1910” (typeface), d) “Museum Paris ex. Coll. R. Oberthur ” (typeface, yellow label), e) " Peltonotus malayensis Arrow ♀ Lectotype " (our yellow lectotype label), f) “ Peltonotus gracilipodus Jameson and Wada Paratype ”.

Description (males=11, females=7). Length 14.4–17.2 mm. Widest width 7.2–8.3 mm. Color: Male (Fig. 6): Head, pronotum, scutellum, propygidium, pygidium, and venter shining castaneous to black; elytra reddish­brown with iridescent bloom. Female (Fig. 7): Head, pronotum, scutellum, propygidium, pygidium, and venter shining castaneous to black; elytra black with iridescent blue bloom. Head (Fig. 15): Surface of frons with base impunctate to sparsely punctate, middle of frons to apex densely punctate; punctures ocellate, multisetigerous (less setigerous in females); short setae on disc (1–12 per puncture), moderately long setae (1 per puncture) adjacent to eye. Surface of clypeus densely punctate; punctures ocellate, multisetigerous (less setigerous in females); short setae on disc (1–12 per puncture). Clypeus laterally weakly bowed, apex truncate, corners square, beaded; bead weakly arcuate posteriorly. Labrum broadly emarginate at middle. Mandibles of male and female rounded laterally, inner apex with 2 teeth. Mentum (Fig. 22) with apical half rounded, notched at middle; palpomere 2 dorsoventrally flattened, twice width of palpomere 1, setose; setae dense, moderately long, rufous, some curled at apex, some flattened. Maxilla (Fig. 30): mala with weak lamellate setal brush; stipes with setae dense, long, not flattened, curled at apex; palpomere 2 with weak internomedial bump. Antennal club subequal to segments 2–7. Pronotum: Bead lacking anterior to scutellum. Surface moderately densely punctate, punctures ocellate, some multisetigerous laterally in males; setae minute. Lateral margin lacking long setae. Elytral sutural length: About 4.0 times length of scutellum. Elytron: Surface with 5 poorly developed, punctate, longitudinal striae between suture and humerus; punctures moderate in size, moderately dense. Intervals with similar sculpturing. Epipleuron of female in ventral view expanded, incised at apex; in dorsal view expansion well­developed (Fig. 55). Propygidium: Surface moderately densely punctate; punctures ocellate, unisetigerous; setae moderately long, rufous. Pygidium: Surface densely punctate; punctures ocellate, mixed small and large, multisetigerous; setae short (over 15 per puncture) and moderately long (1 per puncture). Venter: Prosternal keel triangular; apex projecting anteriorly at about 70° with respect to ventral plane; apex produced to middle of protrochanter, rounded. Legs (Fig. 31): Foretibia of male bidentate; lateral margin with short, dense setae. Foretarsomere 5 of male subequal in length to tarsomeres 1–4; foretarsomere 3–4 with apices expanded, dorsal and ventral apices clothed with dense, short setae. Foreclaws of male with inner claw roundly curved, about 4 times thicker than outer claw; outer claw simply arcuate, about 1/2 the length of inner claw; empodium bulbous at base. Foreclaws of female 2/3 length of foretarsomere 5, claws angled toward venter. Meso­ and metatibial claws of male with 2 setae. Metatibia of male with apical spurs weakly curved spurs; ventral spur produced to middle of metatarsomere 1, dorsal spur produced to middle of metatarsomere 2. Parameres: Fig. 43a–c.

Diagnosis. Peltonotus malayensis is distinguished from other species in the genus based on the following characters: labrum broadly emarginate at middle apex; palpomere 2 dorsoventrally flattened, setose (some setae curled at apex); mala with weak lamellate setal brush; stipes with setae curled at apex; palpomere 2 with weak internomedial bump; foretibia of male bidentate with short, dense setae at lateral margin; form of male genitalia (Fig. 43a–c); epipleuron of female in ventral view expanded, incised at sternite 3, in dorsal view expansion moderately developed (Fig. 55).

Distribution (Fig. 65). Brunei (Borneo); Sarawak State, Bornean Malaysia; and West Kalimantan Province, Bornean Indonesia.

Locality records (18 specimens) from BMNH, WADA, FUJI, MLJC .

BORNEAN INDONESIA. West Kalimantan Province (12): Mt. Bawang, Pontianak.

BORNEAN MALAYSIA. Sarawak State (1): Mt. Dulit (at junction of Tinjar and Lejak Rivers).

BRUNEI (BORNEO). Kaula Belalag (5).

Temporal Data. February (4), March (2), April (4), July (1), August (1), October (1), November (1), December (2).

Natural History. The scant knowledge of natural history of Peltonotus species is based on observations of P. malayensis males and females in inflorescences of aroids at night (see discussion under “Natural History” of the genus Peltonotus).

Remarks. This species is sexually dimorphic for elytral color: males have reddishbrown elytra and females have black elytra with an iridescent bloom. Arrow (1910) described this species based on female specimens. In 1931, Arrow (Arrow 1931) noted that males of this species were still unknown.