Pachyrhynchus obumanuvu Cabras, Donato, Medina, & Van Dam, 2021

Cabras, Analyn Anzano, Medina, Milton Norman, Donato, Joshua & Van Dam, Matthew H., 2021, Pachyrhynchus obumanuvu sp. nov., a new species of easter egg weevil (Coleoptera, Curculionidae, Entiminae, Pachyrhynchini) from Mindanao Island, Philippines, Baltic Journal of Coleopterology 21 (1), pp. 43-48 : 4-7

Pachyrhynchus obumanuvu Cabras, Donato, Medina, & Van Dam sp. nov.

( Fig. 1 A–D )

Material. Holotype ( Fig. 1 A, C ), male: Philippines – Mindanao / Davao City / vi.2019 / Lg. M.P. / coll. UMCRC (typed on white card) // HOLOTYPE male / Pachyrhynchus obumanuvu / CABRAS, DONATO, MEDINA , & VAN DAM 2021 (typed on red card). Presently in UMCRC, it will be deposited in Philippine National Museum of Natural History ( PNMNH) under the National Museum of the Philippines ( NMP).

Paratypes. 4 males, 3 females: same data with holotype. Presently in UMCRC; 2 males, 2 females, same data with holotype/ coll. CASENT; 1 female, Philippines- Mindanao / Cabanglasan / Bukidnin / X. 2014 / coll. Bollino; 1 female, Philippines- Mindanao / Cabanglasan / Bukidnin / IX – XI. 2016 / coll. Bollino.

Diagnosis: Pachyrhynchus obumanuvu sp. nov. is closely related to Pachyrhynchus ardentius Schultze, 1919 from Siargao Island and Pachyrhynchus corpulentus Schultze, 1922 from Bukidnon. The new species differs from P. ardentius and P. corpulentus by having a pair of elongated spots on both sides of the middle disc, instead of the subtriangular scaly patch in P. ardentius and thin longitudinal stripe in P. corpulentus . The unique elytral markings with the absence of median spots and presence of extra sub-basal and subapical spots in P. obumanuvu sp. nov. sets it apart from P. ardentius and P. corpulentus .

Description. Dimensions: LB: 11.0 – 13.5 (holotype 13.5 mm, â:13.14). LR: 1.9 – 2.0 (holotype 2.0 mm, â: 1.99). WR: 1.9 – 2.0 (holotype 2.0 mm, â:1.99). LP: 3.5 – 4.0 (holotype 4.0 mm, â:3.93). WP: 4.0 – 4.5 (holotype 4.5 mm, â:4.43). LE: 8.3 – 9.5 (holotype 9.5, â:9.33). WE: 5.4 – 6.0 (holotype 6.0, â:5.91). N=7.

Integument dark burnished red with a weak greenish sheen. Body dorsal surface, rostrum, head glossy, and ventral surface moderately shiny.

Body mostly subglabrous with very fine hairs and lustrous yellow green to turquoise recumbent round scales. Head subglabrous, with sparse minute hairs on ventral side and scaly markings of metallic light yellow-green, recumbent, and round to elliptic scales forming the following: a) two small spots in the forehead between eyes, and b) subelliptic patch on lateroventral parts behind eyes; forehead between eyes weakly depressed; lateroventral parts wrinkled. Rostrum as long than as wide (LR/WR: 1.0), weakly depressed on basal half, apical half weakly bulging with nearly obscure sulcus towards margin, dorsum with very minute pubescence, lateral surface with a patch of dense, shiny light-yellow recumbent scales, and long brown hairs at the anterolateral margin. Eyes small-sized and feebly convex. Antenna strongly clavate, scape shorter than the funicle, with sparse, fine and very minute hairs towards the apex. Funicle with longer suberect brown hairs. Funicular segment I nearly 1.5 time longer than wide; segment II slightly longer than segment I, nearly twice longer than wide; segments III-VI nearly as long as wide; segment VII slightly longer than wide; club sub-ovoid, nearly twice longer than wide.

Prothorax subglobular, slightly wider than long (LP/WP: 0.88), mostly glabrous, widest at middle, weakly convex, and with metallic light yellow-green, and turquoise round scales. Prothorax with the following scaly markings of metallic light yellow-green and turquoise round scales: a) thin band at the lateral side of anterior margin, b) two elongated spots on both sides of the middle of disc, and c) thick patch in lateroventral stripe before the coxa confluent with the short scaly band on anterior margin.

Elytra ovate (LE/WE:1.58), wider and twice longer than prothorax (WE/WP: 1.33, LE/LP: 2.38), glowing red, sub-glabrous, moderately convex with very minute and sparse punctures and pubescence. Each elytron has scaly patches of metallic light yellow-green, and turquoise recumbent round scales forming the following: a) three subbasal patches with the dorsal and lateral patch both elliptical, and the middle subcircular, b) one small sub circular patch just below or at times in between the middle sub-basal patch and the lateral elliptical patch, c) median transverse band extending from middle towards lateral side but not reaching margin, d) antemedian stripe in the lateral margin extending towards apex, e) postmedian subsutural stripe extending towards apex confluent with the antemedian, lateral margin stripe, f) thin elliptical stripe between the subsutural and sutural patches, g) postmedian elliptical patch along suture, h) subapical elliptical patch along suture, i) oblique reniform subapical patch, and j) thin elliptical subapical spot near the lateral margin.

Legs with moderately clavate femora. Femora covered with lustrous light-yellow and turquoise round scales towards apical margin. Tibiae covered with subrecumbent brown bristles, and moderately serrate along inner edge. Fore and mid tibiae bear a mucro at apex. Tarsomeres covered with dense pubescence. Coxae with sparse brown hairs. Mesepisterna with round scaly patch of light yellow and greenish round scales. Metasternum moderately rugose on disc, covered with light yellow and greenish round scales. Ventrite I weakly rugose, feebly depressed on disc with scaly spot of yellow and greenish round scales on both distal ends. Ventrite II nearly covered with light yellow and greenish round scales. Ventrites III-V bare. Apical half of Ventrite V with sparse subrecumbent brown hairs. Male genitalia as shown in Figure 3A–C .

Female. Dimensions: LB: 12.0-13.5 mm (â:13.0): LR: mm 1.9: WR: 1.9. LP: 3.5. WP: 4.0. LE: 8.5- 9.4 (â: 8.77). WE: 6.5. N=5

Habitus as shown in Figure 1 A-D.

Females differ from males by having wider elytra (LE/WE: 1.31-1.44) and weakly bulging Ventrite I on disc. Otherwise mentioned, similar to the male.

Etymology. The specific epithet is named after the Obu-Manuvu, one of the indigenous tribes of Davao City.

Distribution. Pachyrhynchus obumanuvu sp.nov. is known so far from Davao City.

Notes on Distribution and Habitats

The specimens of Pachyrhynchus obumanuvu sp. nov. were collected in the western side of Davao City. The area is characterized by hilly topography and the vegetation type is a mixture of agricultural and secondary forests. The specimens were collected along a narrow trail in a steep mountain slope with lush vegetation of various species of ferns, aroids, or ch ids, an d oth er sh r ubs. Th e auth or s could barely recognize the species of trees on the steep slope due to th e lush fer n s an d shrubs. The new species was collected while perching on the leaves and stem of Procris urdanetensis Elmer (family Urticaceae ), a Philippine endemic species, and Elatostema sp. (family Urticaceae ). There were lots of bite marks on the leaves of Procris urdanetensis Elmer and Elatostema sp. which suggest that it can be its food plant. The association of the endemic Pachyrhynchus species with endemic plants was also noted by Schultze (1923). The specimens were collected using a beating sheet and handpicking around 8:00 to 10:00 in the morning where they were found inactively perching. The authors do not wish to disclose the exact location in print to avoid over collection of the species by commercial collectors as in Pérez-García 2010, the GPS coordinates are available on the specimens’ label data.

Figures

Fig. 1. Pachyrhynchus obumanuvu sp. nov. - A, C, Holotype male; A. dorsal view, C. lateral view. B, D, Paratype female; B. dorsal view, D. lateral view

Fig. 3. Ecological notes about Pachyrhynchus obumanuvu sp. nov.: A. Habitat in Davao City, B. Procris urdanetensis Elmer, C. Elatostema sp., possible food plant, D. bitemarks on Elatostema sp., E. P. obumanuvu sp. nov perching on the leaves, F. P. obumanuvu sp. nov. on stem