Nyphaeba Pascoe

Riedel, Alexander, 2017, The weevil genera Nyphaeba Pascoe and Pantiala Pascoe and the problems of an unstable nomenclature in orphaned taxa, Zootaxa 4244 (3), pp. 377-389 : 378-379

Nyphaeba Pascoe

Nyphaeba Pascoe, 1871a: 203 .

Type species: Nyphaeba monommoides Pascoe , by subsequent monotypy: Pascoe 1871b: 265.

Redescription. Length 3.68–5.30 mm. Habitus subovate, sides subparallel; in profile convex, with constriction between pronotum and elytron. Integument largely subglabrous, with small patches of scales. Rostrum ca. 0.75 X length of pronotum; parallel-sided or weakly converging to apex; in profile weakly curved; dorsoventrally compressed; in apical half slightly more slender in female; in both sexes dorsal surface without carinae, subglabrous and sparsely punctate in apical half, coarsely punctate in basal half. Antennae inserted slightly in front of middle. Scrobe parallel to rostral contour, meeting anterior margin of eye. Scape subequal to funicle, subglabrous; funicle robust, subglabrous, with sparse thin setae. Club subovate. Eyes large, with subtriangular outline, in dorsolateral position, medially approximate, separated by 0.4 X basal width of rostrum. Forehead coarsely punctate. Pronotum 1.5-1.6 X wider than long; widest at base, sides subparallel in basal half, markedly converging in apical half; with shallow subapical constriction; dorsally densely punctate, laterally coarsely punctate or foveate. Postocular lobe subangular. Scutellar shield distinct, subglabrous. Elytron with 10 distinct striae; stria 10 abbreviated at level of metacoxa, separated by lateral carina originating from elytral base below humerus; sutural interval behind scutellum with swelling and /or distinct sculpture; base sinuate or almost straight; subapically on ventral side without stridulatory file. Wings fully developed. Thoracic venter ( Fig. 5a ). Mesothoracic receptacle broadly U-shaped, wider than long, cavernous, internally glabrous, with ventral rim swollen, punctate-rugose, sparsely squamose. Metaventrite with coarse punctures; anteromedially and posteromedially with deep fovea, anterior fovea transverse, posterior fovea elongate. Metanepisternum distinct, subglabrous except one longitudinal row of coarse punctures; anapleural suture complete, without sclerolepidia. Legs. Femora ventrally sulcate; profemur in basal 1/3 with distinct tooth (with indistinct angulation in N. germari (Faust)) ; meso- and metafemur edentate. Metafemur with posterior face flattened, at middle with patch of fine parallel ridges ( Fig. 5 d). Tibiae with dorsal contour convex, with fine carina; apically with strong uncus, without premucro; mesotibia subbasally with dorsal angulation. Tarsi elongate, slender, third tarsomere 1.5 X as wide as second tarsomere. Abdominal venter with ventrites 1-2 convex, punctate. Ventrite 1 with anterior margin bordered by dense row of coarse punctures; with row of short ridges curving along posterolateral angle ( Fig. 5c ), presumably acting together with metafemur as stridulatory device; intercoxal process subangulate, wider than long. Ventrites 3- 5 flat. Ventrite 5 short, ca. 3 X as wide as long. Female terminalia. Tergite VII wider than long; microsetae absent; basal margin straight; apical margin convex. Tergite VIII longer than wide; apical margin subtruncate, crenulate. Sternite VIII elongate, narrowly Y-shaped, with apical arms separate and parallel for half its length; membrane ventrally free to apex of apodeme, forming a large elongate pocket. Bursa without sclerites. Spermathecal duct arising at junction of oviduct and bursa. Male terminalia. Tergite VII wider than long; without microsetae. Tergite VIII apically subtruncate; dorsally with plumose scales. Sternum VIII with hemisternites small, nude. Spiculum gastrale slightly shorter than penis, straight. Tegmen with parameres and apodeme slightly shorter than width of tegminal ring. Body of penis shorter than apodemes, flattened; apex subtruncate or rounded, without setae; laterally well-sclerotized, medially weakly sclerotized, containing large flat endophallic sclerite shaped like an arrow-head; transfer apparatus distinct.

Note. Nyphaeba has well-developed wings and metanepisterna and therefore it needs to be removed from Tylodina Lacordaire of Cryptorhynchinae Schoenherr. In the phylogeny of Riedel et al. (2016) it is part of the “ Rhynchodes -group” which is supported by the structure of the female sternite VIII (new placement).

Figures

FIGURE 5 a, c – d. Nyphaeba mimica sp. n., holotype; (a) venter (c) detail of ventrite 1 with row of short ridges marked by arrows (d) posterior surface of metafemur with patch of ridges, presumably acting as stridulatory device together with structures shown in (c). Fig. 5 b. Pantiala illusa Pascoe, venter.