Pachyrhynchus sibuyanensis, Rukmane, 2019

Rukmane, Anita, 2019, To the knowledge of genus Pachyrhynchus Germar, 1824 (Coleoptera: Curculionidae: Pachyrhynchini) species from SMNH (Stockholm, Sweden), with description of a new species from the Sibuyan Island (Philippines), Baltic Journal of Coleopterology 19 (1), pp. 41-50 : 42-46

Pachyrhynchus sibuyanensis sp. nov.

( Fig. 1A, 1B , 2)

Type material. Holotype: Male ( Fig. 1A ) ‘’ PHILIPPINES / ROMBLON / 1984’’ (white rectangular card, written by hand); ‘’ NHRS-JLKB / 000065431’’ (white rectangular card, printed) ; ‘’ HOLOTYPE / Male / Pachyrhynchus sibuyanensis Rukmane, 2019 / det. Rukmane A. 2019’’ (red rectangular card, printed)

Paratypes (2 males, 1 female): ‘’ PHILIPPINES / ROMBLON / 1984’’ (white rectangular card, written by hand); ‘’NHRS-JLKB / 000065432’’ (white rectangular card, printed) ; ‘’ PARATYPE / Male / Pachyrhynchus sibuyanensis Rukmane, 2019 / det. Rukmane A. 2019’’ (red rectangular card, printed). ‘’C. PHILIPP. / SIBUYAN / L. ROMBLON 1982’’ (white rectangular card, written by hand); ‘’NHRS-JLKB / 000065434’’ (white rectangular card, printed) ; ‘’ PARATYPE / Male / Pachyrhynchus sibuyanensis Rukmane, 2019 / det. Rukmane A. 2019’’ (red rectangular card, printed). ‘’C. PHILIPP. / SIBUYAN / L. ROMBLON 1982’’ (white rectangular card, written by hand); ‘’NHRS-JLKB / 000065433’’ (white rectangular card, printed) ; ‘’ PARATYPE / Female / Pachyrhynchus sibuyanensis Rukmane, 2019 / det. Rukmane A. 2019’’ (red rectangular card, printed).

Distribution: Philippines, Romblon province, Sibuyan Island ( Fig. 3).

Description. Male. LB: 10.6 – 11.2 (holotype 11.2; mean 10.87); LP: 3.3 – 3.5 (holotype 3.5; mean 3.4); WP: 3.3 – 3.8 (holotype 3.8; mean 3.57); LE: 7.4 – 8.2 (holotype 8.2; mean 7.8); WE: 4.6 – 5.0 (holotype 5.0; mean 4.8); LR: 1.9 (holotype 1.9; mean 1.9); WR: 1.8 – 1.9 (holotype 1.8; mean 1.83). N = 3 for all measurements. Dorsal habitus as shown in Fig. 1A .

Integument black. Body surface strongly shiny, underside with weaker lustre. Different markings of the round recumbent iridescent pale yellow scales on elytra, prothorax, rostrum and femur.

Head sub glabrous; forehead weakly punctured, less than two times as wide as eye width; eyes relatively small, weakly prominent from the outline of the head. Antennae with glossy surface, mingled with long, light hairs in all length; scape relatively slender, shorter than funicle; funicular segment I more than twice as long as wide, 1.5 times longer than II; segment II 1.5 times/ as long as wide, nearly 2 times as long as III; segments III – V sub equal in length and width, equal in length and width, slightly shorter than segment VI; segment VI bigger, slightly longer than wide, shorter and smaller than segment VII; segment VII slightly longer than wide; club sub ellipsoidal, 1.5 times as long as wide, nearly as long as funicular segments V to VII combined. Forehead without scally markings, weakly punctured, very weakly expressed. Rostrum longer than wide (LR/ WR: 1.06); basal part of the rostrum minutely pubescent; dorsum weakly punctured, with moderately deep triangular concavity on basal part and shallow longitudinal medial groove from the middle of the rostrum to middle of the forehead; shallow transverse groove along midline of the rostrum; two triangular shape scally patches inside concavity, patches interrupted by longitudinal groove; weak apical bulge that flattish dorsally, with a pair of oblique elliptic shallow depressions on the middle; dorsal contour of forehead and rostrum moderately arched in basal half, generally declined to midline and weakly rising to apical 2/3 after gradually declined to apex; patch of scally markings on genae.

Prothorax with the following markings: 1) transverse line along sub apical margin in all length; 2) big patch of scales along each of the lateroventral parts; 3) two elongated scally patches from the medial part of the pronotum to base, reaching basal ¾, patches redirected laterally; Sub globular, wider than long, WP/LP: 1.09; weakly punctured; dorsal contour highest slightly before middle apically; sides gradually rounded; basal margin expressed, weakly arched basally.

Each elytron with the following scally markings: 1) elongated scally patch along interval III, from basal 1/5 to basal 4/5; 2) thick transverse line along midline, from lateral margin to suture; 3) longitudinal line along interval III to IV from the midline to apex where line arches along lateral margin of elytra from apex to midline, where line connects with the transverse line; 4) longitudinal patch of scales along interval IX to lateral margin, from basal 1/5 to basal 4/5; scutellum expressed; elytra strongly shiny, sub ellipsoidal, LE/WE: 1.64, wider than prothorax, WE/WP: 1.32, more than twice as long as prothorax, LE/LP: 2.34; moderately punctured with even intervals; dorsal contour highest just in the middle; sides gradually extending from base, widest just in the middle, then gradually narrowed to apex.

Legs slender, strongly shiny; femur near apical end with few general scales along internal margin; Genitalia as illustrated ( Fig. 2).

Female. LB: 13.0; LP: 3.8; WP: 4.0; LE: 9.1; WE: 6.0; LR: 2.0; WR: 1.9. N = 1. Dorsal habitus as shown in Fig. 1B .

Rukmane A.

Rostrum slightly longer than wide; LR/WR: 1.05; prothorax wider than long; WP/LP: 1.05; elytra wider than in male; LE/WE: 1.52, wider than prothorax; WE/WP: 1.5.

Differential diagnosis. In the general appearance the new species is similar to P. moniliferus Germar, 1824 but differs by various morphological features: 1) prothorax less rounded than in P. moniliferus ; 2) different scally markings on the prothorax; 3) scutellum of the new species expressed; 4) femur near apical end without stripe of scally markings; 5) base of elytra of the new species narrower as compared to highest with of elytra; 6) rostrum of then new species wider, with two scally patches on apical depression; together with unique distribution of the new species that, according to available data, is limited to Sibuyan Island.

Etymology. This new species is named after Sibuyan Island which is the only known locality of this new species.

Rukmane A.

Figures

Fig. 1. Dorsal habitus of P. sibuyanensis sp. nov.; A – male; B – female.