Thyestetha puncticollis Eberle & Riedel

Eberle, Jonas, Tänzler, Rene & Riedel, Alexander, 2012, Revision and phylogenetic analysis of the Papuan weevil genus Thyestetha Pascoe (Coleoptera, Curculionidae, Cryptorhynchinae), Zootaxa 3355 (1), pp. 1-28 : 22-23

Thyestetha puncticollis Eberle & Riedel sp. n.

( Figs. 8 , 17 , 21 , 27, 51–52, 72)

Diagnosis. Pronotum densely punctate with small punctures, black. Elytra dark ferruginous; with distinct small punctures, interstices 1– 2 X diameter of punctures ( Figs. 8 , 17 ). Rostral canal with scales between procoxae. Dorsal squamose line of metafemur moderately dense; male metafemur in apical third with weakly protruding posteroventral ridge. Aedeagus ( Figs. 51–52 ) with apex strongly curved ventrad, rounded; transfer apparatus in dorsal view fusiform.

Description. Holotype, male. Length. Pronotum + elytra: 4.7 mm. Color. Antenna, rostrum and tarsi ferruginous; pronotum, head and legs black; rostral canal ferruginous; elytra, pleural sclerites and remaining ventral surface dark ferruginous. Habitus subovate, in dorsal view almost without constriction between pronotum and elytra ( Fig. 8 ); profile dorsally with constriction between pronotum and elytron ( Fig. 17 ).

Rostrum 5.0 X as long as wide at base, base dorsally with scattered scales. Head. Vertex densly punctate.

Prothorax 1.3 X wider than long; disc and sides punctate with small distinct punctures (except for row of coarse punctures along base), punctation slightly sparser basally, interstices smooth, polished; postocular lobe foveate-rugose; marginal carina externally along edge with whitish scales; with scattered long setae and between procoxae with whitish scales inside rostral canal.

Elytra 1.1 X longer than wide; sides rounded; apex slightly extended, jointly rounded; punctures of striae 1–9 distinctly impressed from base to apex; interstices 1– 2 X wider than diameter of punctures, interstices between punctures of stria 9 ca. 0.5 X diameter of puncture. Metanepisternum 2.4 X wider than high.

Thoracic venter. Meso- and metaventrite laterally with sparse whitish scales; metaventrite submedially behind mesocoxa with pair of conspicuous protrusions. Pro- and mesocoxa densely punctate, squamose; metacoxa subglabrous; trochanter with sparse, coarse punctures containing small scales. Distance between mesocoxae subequal to width of mesocoxa.

Legs. Femora moderately punctate, squamose; meso- and metafemur dorsally with broader scales, dorsal squamose line moderately dense; dorsal squamose line of metafemur conspicuous; anteroventral ridges relatively weak. Metafemur in apical third with weakly protruding posteroventral ridge.

Abdomen. Ventrite 1 with large punctation, laterally densely squamose; center of ventrite 2 coarsely punctate, with few scattered scales; remaining ventrites subglabrous.

Terminalia. Aedeagus ( Figs. 51–52 ). Apex rounded, strongly curved ventrad; lateral orificial sclerites medium-sized, inner portion 2 X longer than outer portion; anterior median orificial sclerite simple between 2nd and 3rd fold (as in Fig. 36 ). Dorsal and ventral contour of transfer apparatus straight; in dorsal view fusiform. Sclerotized part of ventral membrane extending proximad 0.71 X length of aedeagal body from insertion of apodemes.

Allotype, female. Same as holotype except: Rostrum 5.43 X longer than wide. Prothorax 1.28 X longer than wide. Elytra as long as wide; extreme apex slightly more slender. Metafemur with concavity basal to stridulatory patch, posteroventral edge not protruding. Terminalia. Hemisternites of ovipositor 5.25 X longer than wide. Tergite VII 1.71 X longer than wide. Tergite VIII 1.88 X longer than wide. Bursal sclerite at insertion of spermathecal duct markedly sclerotized.

Intraspecific variation. Length, males 4.2–4.7 mm (n=2, x = 4.5 mm), females 4.0– 4.2 mm (n=2, x = 4.1 mm). Profile dorsally more constricted in specimen from Japen Island. Scaling on rostral base more dense in specimen from Vanimo. Female terminalia. Spermatheca with acute, inwards directed outgrowth at tip of cornu in specimen from Japen Island. Apical denticles of crenate pygidium finer or coarser.

Etymology. The epithet is based on a combination of the Latin nouns punctum and collum (puncture and neck) and refers to the strongly punctate prothorax.

Material examined (2 males, 2 females). Male, holotype: PAPUA NEW GUINEA, Sandaun Prov., Vanimo, Denake-Rg. , km 8, 400m, 26.X.1992 ( SMNK). Paratypes: WEST NEW GUINEA, Japen Reg.: 1 female: Japen Isl., Serui, Mantembu, 100–500m, 16.XII.2000 ( ARC); Waropen Reg.: Wapoga River E Asori, km 64, Kwadeva Camp, 2°49'S 136°28'E, [ca. 100m], 10.I.1999 ( NKME). PAPUA NEW GUINEA, Sandaun Prov.: 1 female (allotype), same as holotype.

Distribution ( Fig. 72 ). Japen Reg. (Serui); Waropen Reg. (Wapoga riv.); Sandaun Prov. (Vanimo). Elevation: 100– 400 m.

Figures

FIGURE 72. Distribution of Thyestetha glabra sp. n., T. lubrica sp. n., T. puncticollis sp. n., and T. splendens sp. n..

FIGURES 1 – 9. Habitus of Thyestetha spp., dorsal aspect: (1) T. carbonaria, lectotype; (2) T. discolor sp. n., holotype; (3) T. emarginata sp. n., holotype; (4) T. glabra sp. n., holotype; (5) T. lubrica sp. n., holotype; (6) T. nitida; (7) T. oblita sp. n., holotype; (8) T. puncticollis sp. n., holotype; (9) T. splendens sp. n., holotype.

FIGURES 10 – 18. Habitus of Thyestetha spp., lateral aspect: (10) T. carbonaria, lectotype; (11) T. discolor sp. n., holotype; (12) T. emarginata sp. n., holotype; (13) T. glabra sp. n., holotype; (14) T. lubrica sp. n., holotype; (15) T. nitida, lectotype; (16) T. oblita sp. n., holotype; (17) T. puncticollis sp. n., holotype; (18) T. splendens sp. n., holotype.

FIGURES 19 – 22. Thyestetha spp.: (19) T. glabra sp. n., thanatosis position, lateral aspect, (20) T. glabra sp. n., thanatosis position, ventral aspect. (21) T. puncticollis sp. n., eye, anterolateral aspect. (22) T. glabra sp. n., ventral aspect.

FIGURES 37 – 54. Aedeagus of Thyestetha spp. in dorsal and lateral aspect: (37, 38) T. carbonaria, lectotype; (39, 40) T. discolor sp. n., holotype; (41, 42) T. glabra sp. n., holotype; (43) T. carbonaria, apex of aedeagus, ventral aspect; (44) T. oblita sp. n., holotype, apex of aedeagus, ventral aspect; (45, 46) T. lubrica sp. n., holotype; (47, 48) T. nitida, lectotype; (49, 50) T. oblita sp. n., holotype; (51, 52) T. puncticollis sp. n., holotype and (53, 54) T. splendens sp. n., holotype.

FIGURES 29 – 36. Male terminalia of Thyestetha spp.: (29 – 31) T. glabra sp. n., holotype: (29) tegmen, (30) tergite VII and (31) segments VIII – IX. (32 – 34) T. nitida: (32) tegmen, (33) tergite VII and (34) tergite VIII with sternite VIII and spiculum gastrale. Ostium, lateral aspect: (35) T. discolor sp. n., arrow and dashed line marking bulge between 2 nd and 3 rd fold (36) T. splendens sp. n..