Thyestetha emarginata 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 : 8-9

Thyestetha emarginata Eberle & Riedel sp. n.

( Figs. 3 , 12 , 55–57 , 61–63 , 71 )

Diagnosis. Pronotum uniformly densely punctate, black. Elytra ferruginous; punctures of disc minute ( Figs. 3 , 12 ); in females apex conspicuously emarginate. Rostral canal and marginal carinae covered with scales. Dorsal squamose line of metafemur dense.

Description. Holotype, female. Length. Pronotum + elytra: 4.8 mm. Color. Antenna and tarsi ferruginous; head and rostrum deep ferruginous to black; prothorax and legs black; elytra and remaining ventral surface ferruginous. Habitus subrhomboid, in dorsal view slightly constricted between pronotum and elytra ( Fig. 3 ); profile dorsally constricted between pronotum and elytron ( Fig. 12 ).

Rostrum 6.3 X as long as wide at base. Head. Vertex densely punctate, interstices narrower than diameter of punctures.

Prothorax 1.2 X wider than long; disc and sides uniformly punctate with small distinct punctures (except for row of coarse punctures along base), interstices smooth, polished; postocular lobe densely punctate with large punctures, with few white scales; postocular lobe strongly developed; rostral canal and marginal carinae covered with overlapping whitish and brownish scales.

Elytra as long as wide; sides rounded; apex extended, distinctly emarginate at sutural angle; punctures of striae 1–9 distinctly impressed from base to apex, punctures minute on elytral disc, apically more distinct; interstices 4– 6 X wider than diameter of punctures, interstices between punctures of stria 9 subequal to diameter of punctures, punctures closer to each other in apical portion of elytra. Metanepisternum 2.3 X wider than high.

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

Legs. Femora moderately punctate; meso- and metafemur dorsally with slightly broader scales; dorsal squamose line of metafemur dense; anteroventral ridges distinct.

Abdomen. Ventrites 1 and 2 with large scattered scales arising from punctures; remaining ventrites subglabrous except lateral margins squamose.

Terminalia ( Figs. 55–57 , 61–63 ). Tergite VII ( Fig. 57 ) 1.67 X longer than wide. Hemisternites of ovipositor ( Fig. 63 ) 6.34 X longer than wide. Tergite VIII ( Fig. 56 ) 2.07 X longer than wide. Insertion of spermatecal duct with distinct tripartite sclerite ( Fig. 61 ). Spermatheca ( Fig. 62 ) with tip of cornu grown irregularly.

Intraspecific variation. Length, females 4.8 – 5.0 mm (n=2, x = 4.9 mm). Ferruginous coloration of elytra slightly brighter in paratype.

Etymology. The epithet is based on the Latin emarginatus, -a, -um (emarginate) and refers to the emarginate elytral apex of the females of this species.

Material examined (2 females). Holotype, ARC0566 (EMBL Accession # HE802607 ): WEST NEW GUINEA, Jayapura Reg., Sentani, Gn. Cyclops , S02 31.3’ E140 30.5’, 1200–1420m, 30.XI.2007, beaten ( MZB) . Paratype: WEST NEW GUINEA, Jayapura Reg., Sentani, Gn. Cyclops, 950–1450m, 3.X.1992 ( ARC) .

Distribution ( Fig. 71 ). Jayapura Reg. (Cyclops Mts.). Elevation: 1200–1420 m.

Figures

FIGURE 71. Distribution of Thyestetha carbonaria, T. discolor sp. n., T. emarginata sp. n., T. nitida, and T. oblita 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 55 – 60. Female terminalia of Thyestetha spp.: (55 – 57) T. emarginata sp. n., holotype: (55) sternite VIII, (56) tergite VIII and (57) tergite VII. (58 – 60) T. nitida: (58) sternite VIII, (59) tergite VIII and (60) tergite VII.

FIGURES 61 – 65. Female genitalia of Thyestetha spp.: (61 – 63) T. emarginata sp. n., paratype: (61) tripartite sclerite at insertion of spermathecal duct. T. emarginata sp. n., holotype: (62) Spermatheca. (64 – 65): T. nitida (64) ovipositor, lateral aspect.