Phaenonotum dubium Sharp, 1882 (= Phaenonotum exstriatum (Say, 1835))

Deler-Hernandez, Albert & Fikacek, Martin, 2016, Redescriptions and lectotype designations of Central American species of Phaenonotum Sharp (Coleoptera, Hydrophilidae) based on the type material from the David Sharp collection, ZooKeys 579, pp. 83-98 : 88

Taxon classification Animalia Coleoptera Hydrophilidae

Phaenonotum dubium Sharp, 1882 (= Phaenonotum exstriatum (Say, 1835)) Figures 1c, 4c

Hydrophilus exstriatus Say 1835: 171. Trasferred to Phaenonotum by Sharp (1882: 98).

Phaenonotum dubium Sharp, 1882: 98. Synonymized with Phaenonotum exstriatum by Smetana (1978: 14).

Phaenonotum dubium For complete synonymy of Phaenonotum exstriatum see Hansen (1999).

Type material examined.

Lectotype (designated by Smetana 1978: 14): male (BMNH): "Phaen / cyclonotum / dubium / D.S. / S. Geronimo. / Guatemala / Champion // B.C.A. I. 2. / Phaenonotum / dubium , / Sharp. // S. Geronimo. / Guatemala / Champion. // LECTO- / TYPE [round label with purple margins]". Paralectotype: 1 unsexed specimen (BMNH): "Phaen / Cyclonotum / dubium / Types / D.S. / S. Geronimo. / Guate- / mala. Champion. // B.C.A. I. 2. / Phaenonotum / dubium , / Sharp. // San Geronimo. / Vera Paz. / Champion. // Type / H. T. [round label with red margins]".

Other type material.

Sharp (1882) also examined specimens from Mexico: Cordova, Vera Cruz, Oaxaca and Costa Rica: Cache, all of which have to be considered as paralectotypes. We did not examine these specimens.

Additional material examined.

male (dry-mounted) (NMPC): CUBA: Granma Prov: Cauto Cristo, Río Cauto, El Sitio, 01.v.2005, Coll. L. Chaves. male (dry-mounted) (BMNH): HAITI: Port au Prince, 1.iii.1908, Coll. Dr. M. Cameron, B. M. 1936-555. male (dry-mounted) (BMNH): JAMAICA: Kinstong, 16.ii.1908, Coll. Dr. M. Cameron. male (dry-mounted) (BMNH): USA: Delaware (ABTC000175) (NMPC).

Type locality.

San Geronimo, Guatemala.

Redescription.

Habitus as in Fig. 1c. Body length 3.5-3.7 mm (lectotype: 3.5 mm). Body form oval in dorsal view (Fig. 1c), elytra convex in lateral view. Dorsal surface dark brown (Fig. 1c). Antennae and maxillary palpi testaceous. Pronotum slightly paler than elytra. Ventral surface reddish brown. Leg reddish, tarsomeres yellowish. Head with fine and sparse punctures. Pronotum with punctures of same size as on head. Elytral punctation strongly impressed, much denser than on pronotum and head. Epipleura very broad throughout. Meso- and metaventral processes fused into a common keel; mesoventral process arrow-head shaped with an distinct hood, as wide as metaventral process basally, metaventral process slender, parallel-sided, length of metaventrite medially (including metaventral process) ca. four times longer than mesoventral process; metathoracic discrimen indistinct (Fig. 3f). Profemora with long sparse pubescence in basal 0.75. All tarsi with long setae on ventral surface. Aedeagus (Fig. 4c) 0.4 mm long, with median lobe reaching apices of parameres or nearly so; basal portion of median lobe nearly straight laterally, apical portion widely rounded, median lobe nearly of the same width throughout; shape of the gonopore transversely oval. Parameres strongly sinuate in median region. Phallobase as long as wide (Fig. 4d).

Comments on synonymy.

Examined type specimens of Phaenonotum dubium morphologically correspond with specimens of Phaenonotum exstriatum listed in "Additional material examined" in all characters, including morphology of the aedeagus and meso-metaventral process. Hence, we confirm that Phaenonotum dubium is a junior synonym of Phaenonotum exstriatum , as proposed by Smetana (1978).