Thyestetha glabra 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 : 9-11

Thyestetha glabra Eberle & Riedel sp. n.

( Figs. 4 , 13 , 19–20, 22 , 24, 29–31, 41–42, 72)

Thyestetha carbonaria Faust : Voss, 1960: 343.

Diagnosis. Disc of pronotum smooth, polished, with small punctures in apical 1/4, black. Elytra black, disc glabrous, striae largely effaced; apex laterally punctate ( Figs. 4 , 13 ). Rostral canal subglabrous. Aedeagus ( Figs. 41–42 ) apically converging with straight sides. Transfer apparatus in dorsal view at middle strongly constricted.

Description. Holotype, male. Length. Pronotum + elytra: 4.3 mm. Color. Antenna ferruginous, rostrum and tarsi dark ferruginous; remainder black. Habitus subovate, in dorsal view almost without constriction between pronotum and elytra ( Fig. 4 ); profile dorsally with shallow constriction between pronotum and elytron ( Fig. 13 ). Rostrum 5.5 X as long as wide at base. Head. Vertex distinctly punctate.

Prothorax 1.2 X wider than long; anterior 1/4 of disc punctate with small punctures, remainder subglabrous and with minute punctures (except for row of coarse punctures along base); sides punctate with small punctures; postocular lobe coarsely punctate with larger punctures; marginal carina externally along edge with few whitish scales; inner surface of rostral canal with scattered long setae.

Elytra as long as wide; sides rounded; apex slightly extended, jointly rounded; striae effaced on elytral disc, striae 8 and 9 apically distinct; interstices between punctures of stria 8 equal to diameter of punctures, interstices between punctures of stria 9 small. Metanepisternum 3.7 X wider than high.

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

Legs. Femora basally sparsely punctate, apically denser, scales slender; meso- and metafemur dorsally with broader scales; metafemur with denser scaling, dorsal squamose line moderately dense; anteroventral ridges relatively weak; with posteroventral ridge in apical third moderately protruding.

Abdomen. Ventrite 1 laterally and center of ventrite 2 with few thin scales arising from punctures; remaining ventrites subglabrous except lateral margins slightly squamose.

Terminalia. Aedeagus ( Figs. 41, 42 ). Apex strongly curved ventrad, sides converging in straight line; lateral orificial sclerites small, outer portion 2– 3 X longer than inner portion; anterior median orificial sclerite with small bulge between 2nd and 3rd fold (as in Fig. 35 ) Transfer apparatus in profile shallowly incised at middle, ventral contour angularly projecting; anterior and posterior ends curved ventrad; in dorsal view strongly constricted at middle, anterior portion narrower than posterior portion. 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 6.1 X longer than wide. Prothorax 1.2 X longer than wide. Elytra 1.0 X longer than wide; extreme apex slightly more slender. Metafemur without concavity basal to stridulatory patch, posteroventral ridge not protruding. Terminalia. Hemisternites of ovipositor 5.75 X longer than wide. Tergite VII 1.67 X longer than wide. Tergite VIII 2.50 X longer than wide. Bursal sclerite at insertion of spermathecal duct weakly sclerotized.

Intraspecific variation. Size: Length 3.7–4.3 mm (n=3, x = 4.1 mm) in males, 4.1–4.9 mm (n=3, x = 4.5 mm ± 0.4 mm) in females. Legs black or dark ferruginous (few specimens). Male terminalia. Spiculum gastrale of slightly variable length.

Etymology. The epithet is based on the Latin adjective glaber, -bra, -brum (hairless, smooth) and refers to the smooth dorsal surface of this species.

Material examined (51 males, 53 females). Male, holotype, ARC1355 (EMBL Accession # HE802612 , HE802624 , HE802637 , HE802643 , HE802652 , HE802660 ): PAPUA NEW GUINEA, Morobe Prov ., Sattelberg , S06° 29.422' E147°46.219' to S06°29.235' E 147° 46.107', 750–880m, 21-X-2009 ( SMNK) . Paratypes: PAPUA NEW GUINEA, Morobe Prov., 3 males, 5 females: Sattelberg, S06°29.225' E147°46.272' to S06°29.235' E147°46.107', 810–865m, 18.X.2009 ( SMNK) ; 1 male, 2 females: Sattelberg, S06°28.845' E147°45.463' to S06°28.805' E147°45.200', 965–1015m, 28.X.2009 ( SMNK) ; 1 male, 2 females (1 marked ARC 2338, EMBL Accession # HE802619 , 1 marked allotype: ARC 2337, EMBL Accession # HE802618 ): Sattelberg, S06°29.422' E147°46.219' to S06°29.235' E 147° 46.107', 750–880m, 19.X.2009 ( SMNK) ; 1 male (marked ARC 1354) , 1 female (marked ARC 1356, EMBL Accession # HE802613 , HE802625 , HE802644 , HE802661 ): Sattelberg, 21.X.2009 ( SMNK) ; 1 female: Sattelberg, 100–800m, 18.X.1992 ( ARC) ; 3 males, 3 females: Sattelberg, 670–750m, 19.X.2009 ( SMNK) ; 21 males, 14 females: Sattelberg, 750–880m, 19-X-2009 ( SMNK) ; 10 males, 7 females: Sattelberg, 670–870m, 20.X.2009 ( SMNK) ; 1 female: Sattelberg, 670–870m, 20.X.2009 ( SMNK) ; 8 males, 11 females: Sattelberg, 750–880m, 21.X.2009 ( SMNK) ; 2 males, 3 females: Sattelberg, Huon Golf, Biró, 1899 ( HNHM) ; 1 male, 2 females: Yuwong vill., S05°51' E146°43', 250m, 08.I.2003 ( GPSC) .

Distribution ( Fig. 72 ). Morobe Prov. (Sattelberg). Elevation: 750– 965 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..