Piezonotus asper (Pascoe) Riedel, 2024

Riedel, Alexander, 2024, Taxonomic review of weevils of the tribe Celeuthetini, mainly from Sundaland, Sulawesi and the Lesser Sunda Islands (Coleoptera, Curculionidae, Entiminae), Zootaxa 5464 (1), pp. 1-75 : 52-54

Piezonotus asper (Pascoe) , comb. n.

Isomerinthus asper Pascoe, 1881: 591 . Type locality: Tondano.

Picronotus asper (Pascoe) : Marshall, 1956: 106–108.

Description. Lectotype ( Fig. 29a ). Length. Pronotum plus elytron 6.40 mm. Black. Integument squamose with mottled brownish to greyish scales; pronotum and elytron nodulate. Head with angulate transverse sulcus separating rostral base, joined by deep median furrow on forehead. Eyes convex; separated from apex of prothorax by ca. 0.5 X length of eye. Rostrum 1.30 X as long as wide, in basal half sides subparallel, slightly diverging to level of antennal insertion; apical declivity distinct, subglabrous, subapically with few long setae; dorsal profile subangulate, forming knob behind antennal insertion. Antenna. Scape slender; in cross-section subrotund; subapically weakly clavate; with sparse suberect setae. Funicle with article 2 slightly shorter (0.96 X) than article 1. Pronotum as long as wide (0.98 X); with coarse, irregular, subglabrous nodules. Metanepisternum nude. Elytra slender-subovate, 1.47 X as long as wide; striae somewhat obscured by numerous, irregular, subglabrous nodules; interspaces between nodules densely squamose. Legs. Protibia in apical half ventrally weakly denticulate. Venter. Procoxae subcontiguous; distance to apex 0.6 X distance to base of prothorax. Mesoventral process subtriangular, 2.2 X as long as posterior width. Abdomen. Ventrites 1–2 ca. subequal to ventrites 3–5; ventrites 3–5 exposed, well-chitinized, without modifications, subglabrous, with sparse setae. Genitalia. Penis ( Fig. 29b ) in basal half body containing hook-shaped endophallic sclerite. Apex subtruncate, asymmetrical; ostium shifted to left side, occupying ca. ½ of body.Apodeme ca. 2.4 X as long as body of penis. Endophallus long, its middle-part armed with numerous brown spines. Transfer apparatus spiniform, curved, ca. 0.7 X as long as body of penis. Intraspecific variation. Length. Pronotum plus elytron 6.40–7.90 mm. Black to deep ferruginous. Specimens from Tomohon with brownish to greenish mottled scaling; specimen from Modoinding with vestiture coppery with green spots. Female abdominal ventrites 1–2 ca. 1.5 X longer than ventrites 3–5; ventrite 4 forming blade, overlapping ventrite 5; apex of ventrite 4 concave, with sublateral teeth.

Material examined. Type specimens. Isomerinthus asper Pascoe , male, lectotype, by present designation, DNA extraction ARC7527 ( GenBank # OR557463) : INDONESIA, N-Sulawesi, Tondano; labels ( Fig. 29c ); condition: fair, formerly pinned through right elytron; genitalia in glycerol in microtube ( BMNH). Paralectotype: 1 female, ARC7528 (not sequenced) , INDONESIA, N-Sulawesi, Tondano; genitalia in glycerol in microtube ( BMNH). Other material examined: INDONESIA, N-Sulawesi: 2 exx, ARC3564 ( GenBank # LN866380) , ARC6780 , Tomohon, Rurukan, Gn. Mahawu, N01° 21.409´E124° 51.535´to N01° 21.370´E124° 51.676´, 1126–1231 m, 14-V-2012 ( SMNK); 1 ex, ARC7379 , Tomohon, Rurukan, Gn. Mahawu, N01° 20.844´E124° 52.253´to N01° 20.751´E124° 52.129´, 1209–1305 m, 15-V-2012 ( SMNK); 1 ex, ARC6915 ( GenBank # OR541119) , Kotamobagu, Modoinding, Kakenturan, N00° 46.951´E124° 30.427´to N00° 47.053´E124° 30.413´, 1210–1228 m, 19-V-2012 ( SMNK) .

Notes. The subglabrous rostral declivity and the morphology of the female venter may have prompted Marshall to create a new monotypic genus for this species. However, in all the molecular phylogenies at hand it is placed within Piezonotus , which is also supported by the morphology of the male genital.

Figures

FIGURE 29. Piezonotus asper (Pascoe). Isomerinthus asper Pascoe, lectotype: (a) Habitus (b) Penis (c) Labels.