Hydronoplus Fairmaire, 1898

ROBERTO CALDARA, CHARLES W. O’BRIEN & MASSIMO MEREGALLI, 2017, A phylogenetic analysis of the aquatic weevil tribe Bagoini (Coleoptera: Curculionidae) based on morphological characters of adults, Zootaxa 4287 (1), pp. 1-63 : 37-38

Subgenus Hydronoplus Fairmaire, 1898 stat. nov.

Hydronoplus Fairmaire, 1898: 243 (type species: Hydronoplus signatifrons Fairmaire, 1898 ). Klima 1934: 129. Alonso- Zarazaga & Lyal 1999: 88. Oberprieler et al. 2014: 456.

Pseudobagous Sharp, 1917a: 27 (type species: Bagous longulus Gyllenhal, 1836 ). Alonso-Zarazaga & Lyal 1999: 88. Oberprieler et al. 2014: 456; syn. n.

Diagnosis. Body elongate-cylindrical. Rostrum flattened at apex (char. 8.1) and with dorsal surface at point of antennal insertion distinctly angulate (char. 6.1). Scrobe in dorsal view visible for its entire length (char. 15.1). Forehead with tuberculate elevation along margin of eye. Pronotum 0.90x or more as long as broad (char. 26.1). Pronotum with more or less distinctly carinate basal margin across middle one-fourth to one-half. Basal margin of elytra swollen, slightly to markedly costate from scutellum to, or almost to, humerus. Penis body long (char. 57.0). Ventrobasal margin of penis body with short plate extending between apodemes, and therefore visible from above (char. 70.1). Penis body with subapical, ventral depression extending toward base and forming shallow to prominent sulcus (char. 72.1); with dorsolateral, longitudinal furrows, one on each side, forming an acute, raised margin that extends from behind orifice to midlength or further, and dorsal surface markedly convex but depressed below level of lateral margin (char. 62.1). Gonocoxite lacking stylus (char. 117.1), densely setose (char. 119.1).

Remarks. This subgenus is fully supported in all analyses and is one of the most easily distinguishable groups in the Bagoini. Fairmaire (1898) and Sharp (1917a) created the new genera Hydronoplus (here downgraded to subgenus) and Pseudobagous (here synonymized with Hydronoplus ) for B. signatifrons and B. longulus , respectively. Hydronoplus is characterized by nine apomorphies, four in external morphology and five in the shape of male and female genitalia, and includes six Afrotropical species and one Indian species. Since the characterstates sequence was identical in the type species of Hydronoplus and Pseudobagous , only the former appears in the type-species tree ( Fig. 10 ).

Species included. AFR: ¹ Bagous junodi (Sharp, 1917) , ¹ B. longulus Gyllenhal, 1836 , ¹ B. micaceus Hustache, 1924 , ¹ B. promontorii Marshall, 1906 , ¹ B. pilitarsis Hustache, 1923 , *¹ B. signatifrons ( Fairmaire, 1898) . ORR: *² B. nymphaeae Faust, 1888 .

Figures

FIGURE 10. Morphological analysis—type species only. Bayesian consensus tree (50 % majority rule). Taxa in bold font: valid taxa recognized in the present work; larger font: genera, smaller font: subgenera. Taxa in regular font: synonyms in the present work. Numbers above branches: support values, in percentage, in the following order: posterior probability (BI) / bootstrap value (ML) / symmetric resampling (MP); ‘ ns’ means that the group was present, but its support was <50 %; ‘ np’ means that the group was not present. Number below branches: Bremer support in the MP analysis. Scale bar unit: expected changes of state per character. MP analysis: length 146, consistency index = 0.70, retention index = 0.78.