Hydrocanthus, Say, 1823

Guimarães, Bruno A. C., Ferreira-Jr, Nelson & Miller, Kelly B., 2018, On Hydrocanthus Say, 1823 (Coleoptera: Noteridae): description of a new species, two new synonyms and a key to Brazilian species, Zootaxa 4508 (2), pp. 288-300 : 298-299

Key to Brazilian species of Hydrocanthus

1. Male prosternal process partially setose ( Figs 2g , 3h ) or entirely smooth ( Figs 3c, 3e, 3g ); male mesofemur anteroventral margin with a fine setose fringe, rising at base and extending to first ¼ of mesofemur ( Figs 5a , 6a )....................... 2

- Male prosternal process entirely setose except along apical margin ( Figs 2a, 2c, 2e, 2j , 3a ); male mesofemur without modified setae ( Figs 5b , 6b ) or with ventrolateral margin with a tuft of long, rigid setae ( Figs 5c , 6c )........................... 4

2. Males and females prosternum entirely smooth ( Figs 3 c–d) or medially setose ( Figs 3 e–f); Male metaventrite laterally setose, leaving a glabrous triangular area anteriorly ( Figs 3c, 3e ); female metaventrite entirely smooth ( Fig. 3d ) or setose along lateral margins ( Fig. 3f ). {TL = 3.80–5.30 mm; head and pronotum reddish-brown, elytra dark reddish-brown with yellowish marmorations ( Fig. 1i ); aedeagus as Figs 4s–u; distribution in Brazil: Amazonas, Bahia, Ceará, Espírito Santo, Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Paraná, Rio de Janeiro, Rio Grande do Sul, Roraima, São Paulo and Sergipe}........................................................................ Hydrocanthus socius Sahlberg, 1844

- Male metaventrite setose in posterior ¼ or ½, leaving a glabrous rectangular area anteriorly ( Figs 2g , 3 g–h); female metaventrite setose in posterior ½ or ¾, leaving a glabrous triangular ( Figs 2 h–i) or semicircular ( Fig. 3i ) area anteriorly or setose along posterior margin, leaving a glabrous wide area anteriorly ( Fig. 3j )............................................... 3

3. Male and female prosternal process setose along lateral margins with setation bands connecting at the basal center ( Fig. 2 g–i); female prosternum laterally and medially setose ( Fig. 2 h–i), sometimes divided by an irregular glabrous vertical band ( Fig. 2i ). {TL = 4.55–5.50 mm; head and pronotum reddish-brown, elytra very dark reddish-brown with yellowish marmorations ( Fig. 1d ); aedeagus as in Figs 4j–l; distribution in Brazil: Bahia, Espírito Santo, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Paraná, Rio de Janeiro, Rio Grande do Sul, Santa Catarina and São Paulo}.......................................................................................................... Hydrocanthus levigatus (Brullé, 1837)

- Male prosternal process entirely smooth ( Fig. 3g ) or setose along lateral margins ( Fig. 3h ); female prosternum only laterally setose and prosternal process entirely smooth ( Figs 3 i–j). {TL = 4.10–5.10 mm; head and pronotum light reddish-brown, elytra dark reddish-brown with yellowish marmorations ( Fig. 1e ); aedeagus as Figs 4v–x; distribution in Brazil: Bahia, Ceará, Minas Gerais, Rio de Janeiro, Roraima}.......................................... Hydrocanthus marmoratus Sharp, 1882

4. Female prosternal process entirely smooth ( Fig. 3b ); male mesofemur with ventrolateral margin with a tuft of long, rigid setae ( Figs 5c , 6c ). {TL = 4.40–5.20 mm; head and pronotum reddish-brown, black elytra with reddish marmorations ( Fig. 1h ); aedeagus as Figs 4p–r; distribution in Brazil: Paraná, Rio de Janeiro, Rio Grande do Sul and São Paulo}..................................................................................... Hydrocanthus sharpi Zimmermann, 1928

- Female prosternal process entirely setose except along apical margin ( Figs 2b, 2d, 2f, 2k ); male mesofemur without modified setae ( Figs 5b , 6b )................................................................................... 5

5. Metaventrite setose in posterior?, leaving a glabrous subtriangular area anteriorly ( Figs 2 a–b). {TL = 2.80–3.60 mm; head and pronotum light reddish-brown, elytra light reddish-brown with yellowish marmorations ( Fig. 1a ); aedeagus as Figs 4a–c; distribution in Brazil: Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Roraima and Tocantins}............................................................................................. Hydrocanthus ancus Guignot, 1942

- Metaventrite setose in posterior ¼ or ¾, leaving a glabrous triangular area anteriorly ( Figs 2 c–f, 2k) or laterally and posteriorly setose, leaving a glabrous wide area anteriorly ( Fig. 2j )....................................................... 6

6. Male metaventrite laterally and apically setose, leaving a glabrous wide area anteriorly ( Fig. 2j ). {TL = 4.30–4.95 mm; male head and pronotum light reddish-brown, black elytra with reddish marmorations ( Fig. 1f ); female head and pronotum reddishbrown, elytra dark reddish-brown with yellowish marmorations ( Fig. 1g ); aedeagus as Figs 4m–o; distribution in Brazil: Mato Grosso and Pará}.............................................. Hydrocanthus paraguayensis Zimmermann, 1928 - Male metaventrite setose in posterior ¼ or ¾, leaving a glabrous triangular area anteriorly ( Figs 2c, 2e )................. 7

7. Aedeagus as Figs 4d–f. {TL = 3.00– 4.05 mm; head and pronotum light reddish-brown, elytra dark reddish-brown with yellowish marmorations ( Fig. 1b ); distribution in Brazil: Alagoas, Amapá, Amazonas, Bahia, Ceará, Espírito Santo, Goiás, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Paraíba, Piauí, Rio de Janeiro, Rio Grande do Sul, Roraima and São Paulo}.......................................................................... Hydrocanthus debilis Sharp, 1882

- Aedeagus as Figs 4g–i. {TL = 3.15–3.90 mm; head and pronotum light reddish-brown, elytra dark reddish-brown with yellowish marmorations ( Fig. 1c ); distribution in Brazil: Mato Grosso, Pará and São Paulo}........................................................................................................ Hydrocanthus guignoti Young, 1985

Figures

FIGURE 1. Hydrocanthus species dorsal view. a) Hydrocanthus ancus, b) Hydrocanthus debilis, c) Hydrocanthus guignoti, d) Hydrocanthus levigatus, e) Hydrocanthus marmoratus, f) Hydrocanthus paraguayensis male, g) Hydrocanthus paraguayensis female, h) Hydrocanthus sharpi, i) Hydrocanthus socius, j) Hydrocanthus zimmermanni sp. nov. male, k) Hydrocanthus zimmermanni sp. nov. female. Scale bar = 1 mm.

FIGURE 2. Prosternum, prosternal process and noterid platform (metaventrite + metacoxal process), depicting distribution of setae. a) Hydrocanthus ancus male, b) Hydrocanthus ancus female, c) Hydrocanthus debilis male, d) Hydrocanthus debilis female, e) Hydrocanthus guignoti male, f) Hydrocanthus guignoti female, g) Hydrocanthus levigatus male, h) Hydrocanthus levigatus female morphotype A, i) Hydrocanthus levigatus female morphotype B, j) Hydrocanthus paraguayensis male, k) Hydrocanthus paraguayensis female. Scale bar = 2 mm.

FIGURE 3. Prosternum, prosternal process and noterid platform (metaventrite + metacoxal process), depicting distribution of setae. a) Hydrocanthus sharpi male, b) Hydrocanthus sharpi female, c) Hydrocanthus socius male morphotype A, d) Hydrocanthus socius female morphotype A, e) Hydrocanthus socius male morphotype B, f) Hydrocanthus socius female morphotype B, g) Hydrocanthus marmoratus male morphotype A, h) Hydrocanthus marmoratus male morphotype B, i) Hydrocanthus marmoratus female morphotype A, j) Hydrocanthus marmoratus female morphotype B, k) Hydrocanthus zimmermanni sp. nov. male, l) Hydrocanthus zimmermanni sp. nov. female. Scale bar = 2 mm.

FIGURE 5. Hydrocanthus species male left mesofemur in dorsal view. a) Hydrocanthus levigatus, b) Hydrocanthus debilis, c) Hydrocanthus sharpi. Scale bar = 0.2 mm.

FIGURE 6. Hydrocanthus species male left middle leg in dorsal view. a) Hydrocanthus levigatus, b) Hydrocanthus debilis, c) Hydrocanthus sharpi. Scale bar = 0.5 mm.