Notionotus retusus, González-Rodríguez & Short, 2022

Gonzalez-Rodriguez, Liza M. & Short, Andrew Edward Z., 2022, Revision of the water scavenger beetle genus Notionotus Spangler, 1972 in the Neotropical Region (Coleoptera, Hydrophilidae, Enochrinae), ZooKeys 1109, pp. 141-191 : 141

publication ID	https://dx.doi.org/10.3897/zookeys.1109.80775
publication LSID	lsid:zoobank.org:pub:A418DA2C-02DD-4023-A9F8-41FA0AEAAC83
persistent identifier	https://treatment.plazi.org/id/366A532F-DAAF-4521-9E0B-CD6AACA17266
taxon LSID	lsid:zoobank.org:act:366A532F-DAAF-4521-9E0B-CD6AACA17266
treatment provided by	ZooKeys by Pensoft
scientific name	Notionotus retusus
status	sp. nov.

Treatment

Notionotus retusus View in CoL sp. nov.

Figs 8E View Figure 8 , 13F View Figure 13 , 15 View Figure 15

Type material.

Holotype (male): "GUYANA: Region XIII [!sic: Region 8]/ 5°0.730'N, 59°38.965'W, 585 m/ Upper Potaro Camp I (c. 7 km/ NW Chenapau), Ridge Trial/ leg. Short, Baca and Salisbury/ 11.iii.2014; GY14-0311-02A", "DNA VOUCHER/ Extraction #/ SLE-2110" (CBDG). Paratype (1 ex.): Guyana: Region 8: Ayanganna Airstrip, 5°18.264'N, 59°50.257'W; 687 m, trail from airstrip to Ayanganna, leg. A. Short, 18.iii.2014, seepage area over rocks in forest flowing into stream, GY14-0318-01C (1 ex., SEMC, DNA voucher 2372)

Differential diagnosis.

The external characters of Notionotus retusus and N. lohezi are quite similar. The only way they can be separated is by the features of the aedeagus. In this species, the apex of the parameres is wide and rounded (acute in N. lohezi , Fig. 8F View Figure 8 ), the median lobe is much longer than in N. lohezi and the gonopore is elongated and oval (nearly rectangular in N. lohezi ).

Description.

Size and form: Body length 1.8 mm. Body form elongate oval, moderately convex in lateral view. Color and punctation: Dorsally bicolor, head mostly brown, frons brown, clypeus pale brown; pronotum yellow with two small black round spots along posterior margin; elytra dark brown. Ventrally brown; maxillary palps, mouthparts, antennae (antennal club slightly darker), legs brown. Clypeus and labrum with dense, fine, and weakly impressed ground punctation (punctures separated by 2 × their width); pronotum and elytra ground punctation fine, weakly impressed, and sparser than on head (punctures separated by 3 × their width). Head: Clypeus and labrum shallowly emarginate anteromedially, lateral margins of the labrum bearing setae. Thorax: Prosternum carinate medially, strongly raised, acute and pointing anteriorly. Elevation of mesoventrite with two transversal ridges, elevated medially, lateral sides concave; longitudinal ridge broad anteriorly and sharp posteriorly, the point where the three ridges merged wide and blunt (e.g., Fig. 10C, D View Figure 10 ); elevation flat in ventral view; mesoventrite with triangular shape in ventral view. Metaventrite convex in the median region, pubescent with narrow glabrous patch on the medial and posterolateral area; anterior margin extending to mesoventrite elevation. Metafemora with dense hydrofuge pubescence along basal three-quarters of the anterior margin and along basal one-quarter of posterior margin, then apical half of the posterior margin with sparse setae. Abdomen: Abdominal ventrites very densely pubescent. Aedeagus (Fig. 8E View Figure 8 ) with basal piece 0.7 × the length of a paramere. Base of the parameres nearly the same as the base of the median lobe; outer margins convex, inner margins nearly straight; apex of parameres broad, rounded and slightly pointing inwards. Median lobe shorter than the parameres, wide at basal region, narrowing in basal third, margins straight and apex rounded and nearly notched; gonopore with an oval shape and covering approximately two-thirds of the length of the median lobe.

Etymology.

The specific name comes from the Latin word retusus meaning rounded and notched, after the form of the apex of the median lobe of the aedeagus.

Distribution.

This species is only known from the type locality in western Guyana (Fig. 15 View Figure 15 ).

Life history.

This species was collected in detrital-filled pools in a shallow ravine with dense forest cover (Fig. 13F View Figure 13 ). Although the pools might not be considered a stream, the pools were part of a drainage network.

Notionotus rosalesi species group

Diagnosis. The species of this group can be recognized by the unique dorsal coloration, being almost yellow with a wide brown band in the third anterior of the elytra (Fig. 2G View Figure 2 ), the elevation of the mesoventrite with one transversal and longitudinal ridge (e.g., Fig. 10B View Figure 10 ), the shape of the genitalia is quite distinct, being the only one within all Notionotus species of the Neotropical region with the apical third of the parameres membranous (Fig. 9A-C View Figure 9 ).