Novochares minor, Short & Girón, 2023

Short, Andrew Edward Z. & Giron, Jennifer C., 2023, Revision of the Neotropical water scavenger beetle genus Novochares Giron & Short (Coleoptera, Hydrophilidae, Acidocerinae), ZooKeys 1171, pp. 1-112 : 1

Novochares minor sp. nov.

Figs 7C , 11G-K , 13A

Type material.

Holotype (male): "PERU: Loreto: Maynas Province/ 3°50.723'S, 73°22.187'W, 113m/ ca. 10km SW Iquitos, nr. Facultad/ de Ciencias Biologicas UNAP/ leg. S. Baca, 18.i.2020/ seasonal pond; PE20-0118-03A" (MHNSM). Paratypes (41 exs.): Peru: Loreto: Same data as holotype (27, NZCS, SEMC, TTU-Z, including DNA voucher SLE2143); ca. 15 km SW Iquitos, on Iquitos-Nauta Highway, leg. S. Baca, 18.i.2020, flooded area with vegetation and detritus, PE20-0118-05A (10, SEMC); ca. 20 km SW Iquitos, on Iquitos-Nauta Hwy, 3°56.655'S, 73°23.853'W, 107 m, leg. S. Baca, 20.i.2020, shallow margins of lake, with vegetation/detritus; PE20-0120-01A (1, SEMC); ca. 60 km SW Iquitos, on Iquitos-Nauta Hwy, 4°16.279'S, 73°30.734'W, 95 m, leg. S. Baca, 20.i.2020, margin of small creek, inundated grass, PE20-0120-02A (1, SEMC). Suriname: Para: along Martin Luther King Hwy, blackwater marsh by road, 5.4204, -55.09876, SR12-0723-04A (1, SEMC, DNA voucher SLE535). Venezuela: Monagas State: S of Maturin, morichal at road crossing, 9°16.398'N, 62°56.246'W, 22 m, 2.ii.2010, leg. Short, García, & Joly, morichal margin, VZ10-0202-02A (1, MIZA).

Differential diagnosis.

See species group diagnosis.

Description.

Body length 4.2-5.4 mm. Coloration: Dorsal surfaces very dark brown, with paler (orange to yellow) margins of pronotum and elytra. Head: Maxillary palps slightly longer than width of head, orange to brown in color, usually paler (yellow) at ends of each palpomere (Fig. 7C ). Thorax: Ground punctation on pronotum and elytra relatively dense and shallowly impressed. Elytra without rows of serial punctures, each with very faint rows (one dorsal and two or three lateral) of scarce and weakly marked systematic punctures. Prosternum only very weakly medially convex. Posterior elevation of mesoventrite broadly and somewhat transversely elevated; mesoventrite with medial longitudinal glabrous patch extending anteriorly. Abdomen: Apical emargination of fifth ventrite relatively deep, U-shaped. Aedeagus: (Fig. 11G-K ) Overall shape pear-like, 2.1-2.3 × longer than wide, with outer lateral margins of parameres convex up to apical region; apical region of each paramere rounded; at closest point (along neck), dorsal inner margins of parameres separated by distance slightly narrower than greatest width of a paramere; dorsal plate of median lobe with neck 0.5 × as broad as base; base of arms of dorsal plate of median lobe dorsally concave; arms of dorsal plate somewhat parallel to slightly diverging, nearly parallel-sided for most length, nearly 0.23 × length of dorsal plate of median lobe; each arm truncate at apex, sometimes obliquely so, inner margin extending beyond outer margin; notch between arms at base nearly 0.4 × base of an arm; basal piece nearly 0.3 × length of a paramere. In lateral view, ventral outline of parameres 3.5 × longer than greatest width near base; dorsal outline of aedeagus in lateral view strongly convex at base, then very weakly convex along basal 1/2, then sinuate along distal 1/2; ventral outline of aedeagus in lateral view sinuate.

Etymology.

Minor, named after its small body size.

Distribution.

Peru, Suriname, Venezuela (Fig. 13A ).

Habitat.

This species has been found primarily in open marshes and along the margins of vegetated creeks.

Remarks.

There are small differences in overall length/width of aedeagus and the shape of the apicolateral region of the arms of the dorsal plate of the median lobe between specimens from Peru and Venezuela. The small size and form of this species allow it to be easily confused with Sindolus Sharp, but that genus can easily be separated by the strongly raised longitudinal carina of the mesoventrite, which is absent in Novochares .

Novochares orchis species group

Species group diagnosis. Body length 7.3-9.3 mm. Coloration: Dorsal surfaces dark brown and sheeny, with paler (brown or reddish brown) clypeus and margins of pronotum and elytra. Head: Maxillary palps nearly 1.3 × longer than width of head, uniformly reddish brown in color (Fig. 24B ). Thorax: Ground punctation on pronotum and elytra relatively dense and very shallowly impressed. Elytra without rows of serial punctures, each with very faint rows (one dorsal and two or three lateral) of scarce and weakly marked systematic punctures. Prosternum only very weakly medially convex. Posterior elevation of mesoventrite elevated as a triangular pyramid, with medial longitudinal ridge extending anteriorly. Abdomen: Apical emargination of fifth ventrite relatively deep, V- or U-shaped. Aedeagus: (Figs 4B , 11D-F ) Overall shape sub-rectangular, nearly 3 × longer than wide, joint basal margins of parameres truncate; outer margin of each paramere nearly straight along basal 1/2, then weakly sinuate; apical region of outer margin of each paramere pointed; parameres longer than median lobe; apex of parameres rounded to truncate; parameres with apical region variable in degree of sclerotization; dorsal inner margin of each paramere strongly sinuate; dorsal plate of median lobe (in dorsal view) with stout and strongly sclerotized basal apodemes; dorsal plate of median lobe narrower along mid-section than at base, forming a short and broad neck; notch between arms broad; gonopore sitting proximal to base of median lobe; ventral plate of median lobe (in ventral view) triangular, moderately sclerotized; basal piece nearly 0.35 × length of a paramere, with distal margin medially emarginate. In lateral view, aedeagus triangular, weakly oblique at base, with ventral outline of parameres about 4 × longer than greatest width near base.

Composition. This group is composed of a single known species that is found throughout much of the Guiana Shield region with an extremely elaborate aedeagus: N. orchis sp. nov.

Remarks. The large size, very dark brown coloration, and strongly elevated mesoventrite serve to separate this species group from all except the Novochares tectiformis species group. However, we are not aware of any external morphological characters to distinguish it from that group. The species has been placed in its own group largely based on the molecular phylogenetic placement (Fig. 1 ).

Figures

Figure 1. Phylogeny of Novochares spp. Part 1: Novochares punctatostriatus, Novochares tectiformis, Novochares sallaei, Novochares orchis, Novochares minor, and Novochares garfo species groups. Inferred from COI and 28 S combined sequence data. Numbers next to taxon names are extraction numbers (see Table 1). The Novochares portion of the phylogeny of Acidocerinae based on five gene fragments as presented in Short et al. (2021) is reproduced in the lower left corner for comparative purposes.

Figure 4. Aedeagi of the Novochares punctatostriatus, Novochares sallaei, and Novochares orchis species groups along with schematic representations of the whole, the parameres (in blue), and the dorsal (in yellow) and ventral (in red) plates of the median lobe A N. dentatus B N. orchis C N. sallaei.

Figure 7. Dorsal habitus of Novochares spp. A N. abbreviatus B N. pilatus C N. minor D N. tenedor.

Figure 11. Aedeagi of Novochares spp. A-C N. aperito D-F N. orchis G-K N. minor G-J Peru K Venezuela A, D, G, K dorsal view B, E, H ventral view C, F, J oblique view I lateral view.

Figure 13. Distribution of Novochares spp. A N. aperito (red), N. minor (yellow), N. orchis (blue) B N. bidens (red), N. furcatus (yellow), N. garfo (blue), N. tenedor (green).

Figure 24. Dorsal habitus of Novochares spp. A N. tectiformis B N. orchis C N. duo D N. piaroa.