Review of the Neotropical water scavenger beetle genus Tobochares Short & García, 2007 (Coleoptera, Hydrophilidae, Acidocerinae): new lineages, new species, and new records

Abstract The water scavenger beetle genus Tobochares Short & García, 2007 currently contains ten species, including one known but formally undescribed taxon. Although Tobochares was revised in 2017, ongoing fieldwork as well as an expanded concept of the genus has led to the recognition of numerous additional species. Here a combination of morphological and molecular data is presented to review this newly found Tobochares diversity. Fifteen new species are described from South America, bringing the total number of known species to 25: Tobochares akoeriosp. nov. (Suriname), T. arawaksp. nov. (Guyana), T. anthonyaesp. nov. (Venezuela: Bolívar), T. aturessp. nov., (Venezuela: Amazonas), T. benettiisp. nov. (Brazil: Amazonas), T. canaimasp. nov. (Venezuela: Bolívar), T. communissp. nov. (Brazil: Amapá and Roraima, Guyana, Suriname, Venezuela: Bolívar), T. fusussp. nov. (Brazil: Amapá, French Guiana), T. goiassp. nov. (Brazil: Goiás), T. kappelsp. nov. (Suriname), T. kolokoesp. nov. (Suriname), T. luteomargosp. nov. (Venezuela: Bolívar), T. micropssp. nov. (Suriname), T. pemonsp. nov. (Venezuela: Bolívar), and T. romanoaesp. nov. (Brazil: Roraima). Both morphological and molecular analyses support four clades within the genus, which are here diagnosed and described as species groups. New distributional records are provided for T. kusad Kohlenberg & Short, 2017 and T. sipaliwini Short & Kadosoe, 2011, both of which are recorded from Brazil for the first time. Previously restricted to the Guiana Shield region of South America, the distributional range of the genus is now broadly expanded to include localities as far south as the central Brazilian state of Goiás. Consistent with the biology of the previously described species, almost all the new species described here are associated with seepage and wet rock habitats. Remarkably, one species, T. fusussp. nov., was collected in both seepage habitats as well as in the rotting fruits of Clusia Linnaeus (Clusiaceae), making it one of the few known acidocerines with terrestrial habits outside of the genus Quadriops Hansen, 1999. High-resolution images of most species are included, as well as a key to species groups, species, and habitat photographs.

(2017), who recognized ten species, nine of which are described (the tenth species, "sp. A", is known from a single female and was left undescribed). In the process of doing that revision, they encountered a number of additional species that appeared very similar to Tobochares, but also differed in a few notable characters. For example, the anterior margin of the eye is distinctly emarginated by the anterior margin of the frons in all previously described Tobochares (e.g., Fig 2A, B), but not emarginated in these additional species (e.g., Fig. 2D, E). Further, aedeagal forms of these additional species were in some cases quite divergent from those of the described Tobochares, such as exhibiting a bifid median lobe (Fig. 11D, E). These morphological differences, combined with very preliminary molecular data that was available to us at that time, made it unclear if these additional taxa were Tobochares or belonging to a new genus. A recent comprehensive molecular phylogeny of the Acidocerinae confirmed that these additional taxa (i.e., those with unemarginated eyes) do fall outside the previously delimited boundary of Tobochares, but that the generic concept of Tobochares could be expanded relatively easily to include them ; see inset in Fig. 1). In this contribution, we use a combination of molecular and morphological data to (1) establish four species groups within

Morphological methods
Slightly more than 1100 specimens were examined. Specimen preparation and examination methods are identical to those given in Girón and Short (2017). Descriptive sequence and morphological terminology follow Kohlenberg and Short (2017). Descriptions of species are grouped by species group and given in alphabetical order, whereas in the habitus figures, species are grouped by similarity for ease of comparison. Figures presented in Kohlenberg and Short (2017) are referred throughout the text to indicate characters already illustrated there. Maps were created using SimpleMappr (Shorthouse 2010). Type labels are cited verbatim in quotation marks.

Molecular methods
We sequenced the mitochondrial gene COI for eight of the putative 15 new species; we did not have suitable tissue specimens for the remaining species. We also sequenced newly found populations of T. sipaliwini, T. kusad, and T. striatus to further support these species identifications. The number of specimens sequenced per species ranged from one to eleven. All molecular extraction and sequencing methods follow those of Kohlenberg and Short (2017). Resulting DNA sequences were assembled and edited in Geneious R 8.0.5 (Biomatters, http://www.geneious.com/). All sequences are deposited in GenBank (see Table 1 for accession numbers). We combined these newly generated sequences with the COI dataset presented in Kohlenberg and Short (2017) and the Tobochares sequences included in Short et al., (2021). IQ-TREE 1.4.4 (Nguyen et al. 2015) was used to infer phylogenetic relationships. The optimal model of substitution was selected using the Auto function in IQ-TREE 1.4.4. In order to assess nodal support, we performed 1000 ultrafast bootstrap replicates (Minh et al. 2013). We included Crucisternum vanessae Girón & Short, 2018 as outgroup to root the tree.

Results
We found morphological support for 15 new species of Tobochares, which are described in this contribution. The results of the Maximum Likelihood analysis are presented in Fig. 1. The maximum intraspecific pairwise genetic divergence was 3.9% (T. communis sp. nov.). The lowest interspecific pairwise genetic distance between any two species was 7.1% (between T. kusad and T. striatus). We found potential support for four additional new species (sp. 2B, sp. 2C, sp. 15A, sp. 15B) as indicated in Fig. 1, but these species will await description in a future contribution. In addition, we found support for four reciprocally monophyletic species groups, which we were also able to diagnose morphologically. Although our data are not intended to robustly generate a phylogeny of the genus, the circumscription and phylogenetic Figure 1. Maximum Likelihood phylogeny of Tobochares spp. Inferred from COI sequence data. Numbers next to taxon names are extraction numbers (see Table 1). The Tobochares 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.

Remarks on diagnostic features of Tobochares Short & García, 2007
Body shape and coloration. In lateral view, the degree of convexity of the body can be diagnostic, as only a few species (all in the communis species group) are comparatively strongly convex (e.g., T. kolokoe sp. nov., Fig. 9E; T. akoerio, Fig. 8E). Except for a few cases (e.g., the paler elytral margins of T. luteomargo sp. nov., Fig. 5B) the general dorsal coloration of the body in Tobochares is not particularly useful for diagnosis. The coloration of the head is diagnostic for some species of the sulcatus species group.
Maxillary palps. In general, the maxillary palps in Tobochares are short (nearly as long as the width of the head; e.g., Fig. 2A, D, F, H, I) or very short (nearly half as long as the width of the head; e.g., Fig. 2G). The longer palps are slender, as the regular acidocerine maxillary palps (e.g., Crucisternum Girón & Short, 2018), but in the shorter forms, the maxillary palps are also stout: each palpomere is shorter and apically wider (or mesally in the case of maxillary palpomere IV). The coloration of palpomere IV (uniformly yellowish vs. apically darkened) can be diagnostic for some species, especially in the sulcatus species group (see Kohlenberg and Short 2017).
Eyes. The direction of the anterior margin of the eye in dorsal view is partly diagnostic at the species-group level. The anterior margin of the eye is oblique and posteriorly directed in the sulcatus and emarginatus species groups ( Fig. 2A-C), forming a reduced to well-developed canthus, which in lateral view of the head results in a clearly emarginate anterior margin of the eye (Fig. 2B); it is oblique and anteriorly directed to perpendicular to the outer margin of the head in the luteomargo and communis species groups ( Fig. 2D-I), which in lateral view of the head results in a straight anterior margin of the eye (Fig. 2E), only rarely slightly emarginated. The outer margin of the eyes can also be considered diagnostic, being continuous with the outline of the head (eyes not bulging) in the sulcatus species group ( Fig. 2A), or slightly bulging from the outline of the head in the luteomargo and communis species groups (e.g., Fig. 2D, F).
Mesoventrite. The posterior elevation of the mesoventrite exhibits high variation within Tobochares. It usually bears a low, transverse medial ridge, but it can also be  F-i detail of elytral punctation; black marks at top of each circle indicates serial punctures F T. pemon (all punctures relatively large; serial punctures longitudinally aligned; interserial punctures in irregular single row) G T. atures (all punctures longitudinally aligned; serial punctures larger than interserial punctures; interserial punctures more densely distributed) H T. kolokoe (serial punctures longitudinally aligned; interserial punctures forming one or two irregular rows) i T. canaima (serial punctures longitudinally aligned; interserial punctures forming two or three irregular rows) J, K hindwings J T. sipaliwini K T. microps. flat, or with a weakly elevated bulge (Fig. 3E), or a broad and low longitudinal ridge (Fig. 3D). Not necessarily a diagnostic feature at the species-group level.
Metaventrite. The surface of the metaventrite is overall densely covered by hydrofuge pubescence, with a posteromedial glabrous patch. The shape of the glabrous patch is diagnostic at the species-group level: members of the sulcatus species group have a broad, ovoid to diamond-shaped glabrous patch (Kohlenberg and Short 2017: fig. 10), whereas in the luteomargo and communis species groups, the glabrous patch is shaped like a narrow longitudinal bar (Fig. 3D, E).
Elytral punctation. The distribution and characteristics of the elytral punctation are highly variable in Tobochares. The disposition and degree of impression of the elytral punctation (i.e., serial punctures, ground punctures and systematic punctures) are useful for species recognition. The elytral punctures are generally aligned in rows, but this is not so evident in some species (e.g., T. luteomargo (Fig. 5A), T. communis (Figs 3A, 6A), T. microps sp. nov. (Fig. 6D), T. fusus sp. nov. (Fig. 5D)), where the punctures seem to be evenly distributed rather than longitudinally aligned. In species of the luteomargo and emarginatus species groups, and some species in the communis species group all the elytral punctures are similar in size and degree of impression. Most members of the sulcatus species group have well developed, impressed, elytral striae (see Kohlenberg and Short 2017). The sutural striae are always absent in Tobochares, but in T. akoerio (Fig. 8A) and T. romanoae (Fig. 8D) the impressed stria I on each elytron is more strongly impressed along the posterior half of the elytra, which might resemble a well-developed sutural stria. In some species the elytral striae are only impressed along the posterior half or third of the elytra (e.g., T. kasikasima Short, 2013, Kohlenberg andShort 2017: fig. 3C; T. romanoae (Fig. 8D) and T. akoerio (Fig. 8A)).
In some species in the communis species group, the serial punctures can be recognized by their higher density in comparison with interserial punctures (Figs 3H, I, 10A, D), whereas in others the serial punctures are larger and less dense than the interserial punctures (T. atures sp. nov., Figs 3B, G, 7D). Seta bearing systematic punctures are distributed in irregular rows in the sulcatus species group, whereas in the luteomargo and communis species groups, seta bearing systematic punctures are rather scarce, sometimes only evident along the sides and posterior third of elytra (e.g., Fig. 3A-C). Some details of the elytral punctation require high magnification to be properly observed.
Hind wings. Most species of Tobochares have well-developed hind wings (Fig. 3J), with the notable exception of T. microps, which is polymorphic, with individuals exhibiting either full size or brachypterous wing forms (e.g., Fig. 3K).
Metafemora. For the most part, the anterior surface of the metafemora is glabrous, smooth and shiny, with only few scattered setae and very shallow reticulations (Kohlenberg and Short 2017: fig. 12). Sometimes there is a narrow strip of hydrofuge pubescence along the basal half of the anterodorsal margin. Not necessarily a diagnostic feature at the species-group level.
Abdomen. All the abdominal ventrites are uniformly covered by fine pubescence, which varies in density: in T. canthus Kohlenberg & Short, 2017, T. emarginatus Kohlenberg & Short, 2017, and T. luteomargo the pubescence is rather scanty, whereas in the remainder species of the genus the pubescence is very dense (Kohlenberg and Short 2017: fig. 13). The posterior margin of the fifth ventrite is evenly rounded and lacks thick, flat spine-like setae (Kohlenberg and Short 2017: fig. 13).
Aedeagus. As is usual in acidocerines, the configuration of the aedeagus is diagnostic at the species and species-group level, although, it can be considered highly variable within the genus, which is unusual in the subfamily. The basal piece is usually short (between 0.3 and 0.6 × the length of the parameres), except in T. luteomargo, in which the basal piece is slightly longer than the parameres (Fig. 11D). The median lobe varies from roughly triangular and apically rounded (as in most species of the sulcatus species group, Kohlenberg and Short 2017: fig. 14) to rather sagittate, either narrowing along its apical third (e.g., Fig. 11G-I), or apically pinched (e.g., Fig. 11K-M). The apex of the median lobe is rarely emarginate at apex (e.g., Fig. 11D, E). The parameres range in length from shorter to nearly as long as the median lobe, with outer margins straight, broadly curved or sinuate. The overall shape and proportions of the aedeagus, particularly the median lobe, are variable in Tobochares.
Key to the species groups of Tobochares 1 Anterior margin of eye emarginate in lateral view, oblique and posteriorly directed in dorsal view ( Fig  The complete list of species including their assigned species group and known distribution are recorded in Table 2.

Tobochares sulcatus species group
Diagnosis. This species group can be recognized by the oblique and posteriorly directed anterior margin of the eye in lateral view, which emarginates the eye in lateral view   Table 2.

Key to the species of the Tobochares sulcatus species group
Modified from Kohlenberg and Short (2017) 1 Elytra with impressed grooves along their entire length (e.g., Kohlenberg  Differential diagnosis. Tobochares benettii can be easily recognized from all other Tobochares species in the sulcatus species group by its elytral punctures seemingly uniformly distributed, not forming clear longitudinal rows, therefore completely lacking elytral striae (Fig. 4A). This character makes it similar to Tobochares goias, from which it can be distinguished by its uniform orange brown coloration along pronotum and elytra, with dark brown head ( Fig. 4A-C), the posterior elevation of the mesoventrite forming a curved transverse ridge, which is medially prominent and acute and by characters of the aedeagus (Fig. 11A).
Description. Size and form: Body length 1.6-2.0 mm. Body elongate oval, strongly convex (Fig. 4A, B). Color and punctation. Head dark brown, pronotum and elytra uniformly orange brown; antennae, mouthparts and legs orange to yellowish brown, with paler tarsi (Fig. 4C). Ground punctation on head, pronotum and elytra moderately marked. Head: Eyes in dorsal view with anterior margin oblique, posteriorly directed, and outer margins continuous with outline of head (as in Fig. 2A); in lateral view, eyes emarginate to about half the length of eye (as in Fig. 2B). Maxillary palps slender, nearly as long as the width of the head, uniformly yellow in color (as in Fig. 2A). Thorax: Elytra with slightly defined rows of punctures, not forming grooves (Fig. 4A). Elevation of mesoventrite forming a somewhat transverse bulge (Fig. 4C). Metaventrite with distinct median, broad, ovoid glabrous area extending along posterior two thirds (Fig. 4C). Abdomen: Abdominal ventrites uniformly and very densely pubescent. Aedeagus (Fig. 11A) with basal piece 0.25 × the length of a paramere; widest point of parameres (near base) nearly 2/3 greatest width of median lobe (near base), with outer margins slightly sinuate, and rounded apex; median lobe roughly triangular, dorsally concave, apical region nearly half as wide as base, broadly rounded at apex; gonopore situated at apex of median lobe.
Etymology. Named after Cesar J. Benetti, Brazilian specialist on aquatic beetles, in honor of his contributions to Neotropical beetle taxonomy and for all his assistance in the field.
Distribution. Only known from the type locality in Amazonas State, Brazil, situated slightly north of the Amazon River (Fig. 13).
Life history. This only known series was collected on a vertical seepage on sedimentary rock (Fig. 14A, B).  Differential diagnosis. Tobochares goias can be easily recognized from most species in the sulcatus species group by its elytral punctures seemingly uniformly distributed, not forming clear longitudinal rows, therefore completely lacking elytral striae (Fig. 4D). This character makes it similar to T. benettii, from which it can be distinguished by its dark brown coloration, with paler (yellowish to orange) lateral margins of pronotum and elytra (Fig. 4D, E), the posterior elevation of the mesoventrite forming a low and uniform curved transverse ridge (Fig. 4F), and by characters of the aedeagus (Fig. 11B). Description. Dorsal surfaces of body dark brown with paler outer margins of pronotum and elytra (Fig. 4D, E); head slightly darker; mouthparts and antennae yellowish; legs yellowish to brown with paler tarsi (Fig. 4F). Ground punctation on head, pronotum and elytra moderately marked. Head: Eyes in dorsal view with anterior margin oblique, posteriorly directed, and outer margins continuous with outline of head; in lateral view, eyes emarginate to about half the length of eye ( Fig. 2A, B). Maxillary palps slender, slightly shorter than width of head, uniformly yellowish in color ( Fig. 2A). Thorax: Elytra with slightly defined rows of punctures, not forming grooves (Fig. 4D). Elevation of mesoventrite with a low transverse ridge (Fig. 4F). Metaventrite with distinct median, broad, ovoid glabrous area extending along posterior two thirds (Fig. 4F). Abdomen: Abdominal ventrites uniformly and very densely pubescent. Aedeagus (Fig. 11B) with basal piece 0.2 × the length of a paramere; widest point of parameres (near base) nearly as wide as basal width of median lobe, with outer margins very slightly sinuate, and rounded apex; median lobe fusiform, with widest point slightly apicad of midpoint, broadly rounded at apex; gonopore situated at apex of median lobe.
Etymology. Named after the Brazilian state of Goiás, from which the species is known. Distribution. Only known from the type locality in the central Brazilian state of Goiás. This is the first and currently only species of Tobochares reported from south of the Amazon River (Fig. 12).
Life history. This species was collected on wet rock along the margins of the Ribeirão das Lejas. See Fig. 14C.

Tobochares luteomargo species group
Diagnosis. Members of this species group can be recognized by the straight anterior margin of the eye in lateral view (Fig. 2E), the longitudinally aligned and undifferentiated elytral punctures with about the same size and degree of impression (Fig. 5A), the short and narrow glabrous patch on the metaventrite (Fig. 5C), the scantiness of the hydrofuge pubescence on the abdominal ventrites (Fig. 5C), and the reduced (in number and size) metatibial spines.
Composition. This species group currently contains only a single species, T. luteomargo sp. nov. Differential diagnosis. Tobochares luteomargo can be distinguished by the yellow band along the outer margins of the body (Fig 5B).
Etymology. Named with the Greek words luteo, meaning yellow, and margo meaning margin, in reference to the striking yellow band surrounding the marginal areas of these beetles.
Distribution. This species is known from several localities along the northwestern edge of the Guiana Shield in Bolívar State, Venezuela. See Fig. 13.
Life history. Tobochares luteomargo is found on rock seeps on granitic inselberg-like habitat. Some of these seeps may be very small, less than half a square meter in size. The largest series of this species were collected in seeps on which there was abundant apparent lichen growth, and specimens were often hiding under these growths (Fig. 15E).

Tobochares emarginatus species group
Diagnosis. The emarginatus species group can be recognized by the oblique and posteriorly directed anterior margin of the eye in lateral view, which emarginates the eye to about a quarter of its dorsal width ( Fig. 2C; Kohlenberg and Short 2017: fig. 6C-F), the presence of a broad, ovoid to diamond-shaped glabrous patch on the metaventrite (Fig. 5F), the dense and uniform distribution of the hydrofuge pubescence on the abdominal ventrites (Fig. 5F), and the moderate (in number and size) metatibial spines.
Key to the species of Tobochares emarginatus species group Differential diagnosis. Tobochares fusus is externally indistinguishable from T. emarginatus, given that both species share the same disposition and degree of impression of the elytral punctures, and a low transverse ridge on the posterior elevation of the metaventrite. However, they can be clearly differentiated by the general shape of the aedeagus, which is rather slender and nearly parallel sided in T. emarginatus (Kohlenberg and Short 2017: fig. 14I), whereas T. fusus has a fusiform aedeagus (see Fig. 11C).
Description. Size and form: Body length 1.7-2.0 mm. Body elongate oval, moderately convex (Fig. 5D, E). Color and punctation: Dorsal surfaces of body dark brown, with slightly paler pronotum (Fig. 5D); antennae, mouthparts, and legs yellowish brown, with orange tibiae; ventral surfaces of meso-, metathorax and abdomen dark brown (Fig. 5F). Ground punctation on head, pronotum and elytra moderately marked. Head: Eyes in dorsal view with anterior margin oblique, posteriorly directed; canthus emarginating eye to about a quarter of its dorsal width in lateral view (Fig. 2C). Maxillary palps 0.7 × width of head. Thorax: Elytra with all kinds of punctures similar in size and degree of impression, seemingly evenly distributed, not forming grooves (Fig. 5D). Elevation of mesoventrite forming a low transverse ridge (Fig. 5F). Metaventrite with distinct median, broad, diamond-shaped glabrous area extending along posterior two thirds (Fig. 5F). Abdomen: Abdominal ventrites uniformly and densely pubescent (Fig. 5F). Aedeagus (Fig. 11C). Basal piece nearly 0.4 × length of a paramere; greatest width of a paramere nearly 0.7 × greatest width of median lobe; outer margins of parameres diverging along basal half, then broadly bending inward and tapering along apical fifth; apex of paramere oblique, pointing towards longitudinal midline of aedeagus; median lobe roughly triangular, apically rounded; gonopore situated at apex of median lobe.
Etymology. Named with the Latin word fusus, meaning fusiform, in reference to the shape of the aedeagus of this species.
Distribution. This species is known from two closely situated localities on either side of the Oiapoque River, the boundary between French Guiana and the Brazilian state of Amapá. See Fig. 13.
Life history. The series from Brazil were taken from a seepage habitat in a forested riparian corridor (Fig. 14F). A thin layer of saturated dead leaves was laying over granite, over which a thin film of water was seeping into an adjacent stream. The short series from French Guiana was collected from the rotting fruits of a Clusia on an otherwise dry forest floor and not adjacent to any aquatic habitat (Fig. 17C).

Tobochares communis species group
Diagnosis. The Tobochares communis species group can be recognized by the straight anterior margin of the eye in lateral view (e.g., Fig. 2E), the usually longitudinally aligned elytral punctures, the short and narrow glabrous patch on the metaventrite (Fig. 3D, E), the high density of the hydrofuge pubescence on the abdominal ventrites, and the well-developed and numerous metatibial spines.

Key to the species of Tobochares communis species group
1 Elytra with all kinds of punctures relatively large, about the same size and degree of impression, all seemingly longitudinally aligned and uniformly distributed (Fig. 6A, D) Eyes relatively small (ventral face of the eye only slightly wider than antennal club), separated by distance 6 × larger than largest diameter of eye in dorsal view (Fig. 2I)  Body size around 2.6 mm; elytral striae rather shallow (Fig. 8A, B); mesofemur with a well-defined patch of dense hydrofuge pubescence along anterobasal corner (Fig. 8C); metafemur 2.5 × longer than wide (Fig. 8C) (Fig. 8D, E); mesofemur with a reduced patch of scanty hydrofuge pubescence on anterobasal corner (Fig. 8F); metafemur nearly 2 × longer than wide (Fig. 8F)  Serial punctures longitudinally aligned and slightly impressed forming shallow grooves (Fig. 7A); interserial punctures somewhat irregularly distributed in a single row (Fig. 7A)  Serial punctures longitudinally aligned, larger than interserial punctures (Fig. 3B, G); interserial punctures longitudinally aligned, more densely arranged than serial punctures (Fig. 3B, G); median lobe gradually narrowing towards apex from near base (Fig. 11G)  Serial punctures seemingly longitudinally aligned, more densely arranged than interserial punctures (e.g., Fig. 3C); interserial punctures randomly distributed (e.g., Fig. 3H, I); median lobe broad, only narrowing along apical third (e.g., Fig. 11L-N Coloration of pronotum only slightly paler along antero-lateral margin (Fig. 9E); legs reddish brown (Fig. 9F); punctures on outer surface of elytra more strongly impressed along apical region than those on dorsal surface (Fig. 9F)  Elytral punctation sharp and dense (Fig. 10D); apodemes of the median lobe one fourth the length of the median lobe (Fig. 11N) ......Tobochares canaima -Elytral punctation shallow and relatively sparse (Fig. 10A); apodemes of the median lobe nearly half as long as the median lobe (Fig. 11M)  Tobochares akoerio can be recognized by its strongly convex body in lateral view (Fig. 8E), accompanied by elytra with well-defined rows of serial punctures, moderately impressed, forming grooves along apical 3/4 of elytra (Fig. 8D, E); interserial punctures somewhat irregularly distributed (Fig. 8D, E). The general habitus of T. akoerio is similar to that of T. romanoae and T. canaima, especially by the uniformly dark coloration of the pronotum; T. akoerio can be distinguished from these two species by its strongly impressed striae, especially along the lateral regions of the elytra when compared to T. romanoae (compare Fig. 8D, E to 8A, B).

Description. Size and form:
Body length 2.0 mm. Body elongate oval, strongly convex (Fig. 8E). Color and punctation: Dorsal and ventral surfaces of body dark brown, with lateral margins of prothorax only very slightly paler (Fig. 8D, E); mouthparts and antennae yellow, with slightly darker antennal club and apical third of maxillary palpomere IV; legs orange with paler tarsi (Fig. 8F). Ground punctation on head, pronotum and elytra moderately marked (Fig. 8D). Head: Eyes in dorsal view with anterior margin oblique (anteriorly directed), and outer margins slightly bulging from outline of head; in lateral view, eyes not emarginate. Thorax: Elytra with well-defined rows of serial punctures, moderately impressed, forming grooves along apical 3/4 of elytra (Fig. 8D); interserial punctures somewhat irregularly distributed (Fig. 8D). Metafemora mostly glabrous on anterior face, with narrow band of pubescence along basal third of dorsal margin (Fig. 8D). Elevation of mesoventrite forming a low transverse carina (Fig. 8D). Metaventrite with distinct median, longitudinal, narrow glabrous area extending along posterior half (Fig. 8D). Abdomen: Abdominal ventrites uniformly and very densely pubescent. Aedeagus (Fig. 11K). Basal piece 0.4 × the length of a paramere; parameres nearly 1/3 as narrow as greatest width of median lobe, with outer margins widely and uniformly convex, and rounded apex; median lobe roughly triangular, rounded and slightly pinched at apex; gonopore situated nearly at midlength of median lobe.
Etymology. Noun in apposition. Named after the Akoerio, an indigenous nomadic tribe, with only few people remaining in the South of Suriname.
Distribution. The species is only known from an exposed rocky summit in the Grensgebergte Mountains along the border between Suriname and Brazil. See Fig. 13.
Life history. This species was collected on flowing seeps with moss and algae over granite. See Fig. 16F. Differential diagnosis. Tobochares arawak can be recognized by its strongly convex body in lateral view (Fig. 10B), accompanied by elytral punctation uniform in size and degree of impression, with serial punctures seemingly aligned in rows, not impressed to form grooves (Fig. 10A); the interserial punctures are somewhat irregularly distributed in two or three rows (Fig. 10A). The general habitus and punctation of T. arawak are similar to those of T. canaima, T. kappel, and T. kolokoe. In T. kappel and T. kolokoe the interserial punctures form only one or two irregular rows (Fig. 3H). In T. canaima (Fig. 10D) the pronotal and elytral punctations are sharper than in T. arawak and the apodemes of the median lobe are one fourth the length of the median lobe in T. canaima (Fig. 11N), as opposed to half as long in T. arawak (Fig. 11M).
Description. Size and form: Body length 1.6-1.8 mm. Body elongate oval, strongly convex (Fig. 10A, B). Color and punctation: Dorsal and ventral surfaces of body dark brown, with lateral margins of prothorax and elytra only slightly paler (Fig. 10A, B); mouthparts yellow, with slightly darker apical third of maxillary palpomere IV; antennae brown; legs reddish to dark brown with paler tarsi (Fig. 10C). Ground punctation on head, pronotum and elytra moderately marked (Fig. 10A, B). Head: Eyes in dorsal view with anterior margin oblique (anteriorly directed), and outer margins slightly bulging from outline of head; in lateral view, eyes not emarginate (see Fig. 2E). Thorax: Elytra with slightly defined rows of shallow serial punctures, not forming grooves (Fig. 10A); interserial punctures somewhat irregularly distributed in two or three rows (Fig. 3I). Elevation of mesoventrite forming a very low transverse carina (Fig. 10C). Metaventrite with distinct median, longitudinal, narrow glabrous area extending along posterior half (Fig. 10C). Abdomen: Abdominal ventrites uniformly and densely pubescent. Aedeagus (Fig. 11M). Basal piece 0.4 × the length of a paramere; parameres nearly 1/3 as narrow as greatest width of median lobe, with outer margins widely and uniformly convex, and rounded apex; median lobe roughly triangular, rounded and slightly pinched at apex; gonopore situated nearly at midlength of median lobe.
Etymology. Noun in apposition. Named after the Arawak, an indigenous tribe of northern South America.
Distribution. Tobochares arawak is only known from the Upper Potaro region in Guyana. See Fig. 13.
Life history. This species was collected in a wet seepage area along rocks at the margin of the Upper Potaro River. Specimens were collected by pulling back root mats and moss that were growing over the wet rock areas. See Fig. 15A Differential diagnosis. The general habitus and coloration of T. anthonyae is similar to that of several species in the communis group; nevertheless, the elytral punctation T. anthonyae is relatively distinct: all kinds of punctures are relatively large, similar in size and degree of impression, the serial punctures are aligned in rows and slightly impressed, forming shallow longitudinal grooves, and the interserial punctures are somewhat irregularly distributed in a single row (Fig. 7A). The relatively large punctures, similar in size and degree of impression may resemble those of T. communis, but in this species the serial punctures are not impressed to form grooves (Fig. 6A), as they are in T. anthonyae. In addition, the overall shape of the aedeagus, especially the shape of the median lobe of T. anthonyae is unique among members of the communis group: the median lobe gradually and slightly narrows towards a broadly rounded apex, and the gonopore is located near the apex of the median lobe (Fig. 11F).
Description. Size and form: Body length 1.8-2.0 mm. Body elongate oval, moderately convex (Fig. 7B). Color and punctation: Dorsal and ventral surfaces of body, dark brown, with slightly paler margins of pronotum (Fig. 7A, B); mouthparts yellowish brown; antennae light brown; legs orange with yellow tarsi (Fig. 7C). Ground punctation on head, pronotum and elytra rather shallowly marked. Head: Eyes in dorsal view with anterior margin oblique (anteriorly directed; e.g., Fig. 2D), and outer margins slightly bulging from outline of head; in lateral view, eyes not anteriorly emarginate (e.g., Fig. 2E). Thorax: Elytra with all kinds of punctures similar in size and degree of impression (Fig. 7A); serial punctures aligned in rows, slightly impressed, forming shallow longitudinal grooves; interserial punctures somewhat irregularly distributed in a single row (Fig. 7A). Metafemora mostly glabrous on anterior face, with hydrofuge pubescence along basal third of antero-dorsal margin (Fig. 7C). Elevation of mesoventrite forming a low longitudinal bulge (Fig. 7C). Metaventrite with distinct median, longitudinal, narrow glabrous area extending along posterior half (Fig. 7C). Abdomen: Abdominal ventrites uniformly and very densely pubescent. Aedeagus (Fig.  11F). Basal piece 0.3 × the length of a paramere; greatest width of a paramere nearly 0.5 × greatest width of median lobe; outer margins of parameres nearly straight, only slightly curved inwards along apical region; apex of paramere rounded; median lobe roughly triangular, widely rounded at apex; gonopore situated at apical fourth of median lobe.
Etymology. Named after Becky Anthony, program and meetings manager at the Entomological Society of America (ESA), in recognition of all her hard work in service to the society and the entomological community.
Distribution. Only known from a single locality just south of the Orinoco River along the northwestern edge of the Guiana Shield. See Fig. 13.
Etymology. Noun in apposition. Named after Atures, the municipality where the type locality is situated.
Distribution. This species is known from several localities along the northwestern edge of the Guiana Shield in Venezuela. See Fig. 13.
Differential diagnosis. Tobochares canaima can be recognized by its strongly convex body in lateral view, accompanied by elytral punctation uniform in size and degree of impression, with serial punctures seemingly aligned in rows, not impressed to form grooves; the interserial punctures are somewhat irregularly distributed in two or three rows (Fig. 10D, E). The general habitus and punctation of T. canaima are similar to those of T. arawak, T. kappel, and T. kolokoe. In T. kappel and T. kolokoe the interserial punctures form only one or two irregular rows (e.g., Fig. 3H). In T. arawak the pronotal and elytral punctation is shallower than in T. canaima (compare Fig.10A vs. Fig. 10B) and the apodemes of the median lobe are half the length of the median lobe in T. arawak (Fig. 11M), as opposed to one fourth of the length in T. canaima (Fig. 11N).
Etymology. Noun in apposition. Named after the Canaima National Park in Venezuela, where the type locality is situated.
Distribution. This species is known from the famous Auyan-tepui, which is also home to Angel Falls, the highest waterfall in the world. Collected at elevations of 1700-2170 m, this species is one of the relatively few water beetle taxa known from the "Pantepui Province", which comprises areas of the Guiana Shield which are greater than 1500 m in elevation. See Fig. 13.
Life history. The only known series was collected in a flight intercept trap and a yellow pan trap. Nothing further is known about the habitat or biology of this species. Etymology. Named with the Latin word communis meaning common, highlighting the abundance and wide distribution of the species, which is the most commonly found.
Distribution. This species is the most widely distributed of all known Tobochares, occurring from the northwest margin of the Guiana Shield in Venezuela all the way to its eastern edge in the state of Amapá, Brazil (Fig. 12).
Life history. This species is strongly associated with seepage habitats on exposed granite. Many of the seepages on which this species has been collected are seasonal, although others are adjacent to permanent streams. See Fig. 16D Differential diagnosis. Tobochares kappel can be recognized by its strongly convex body in lateral view, accompanied by elytral punctation uniform in size and degree of impression, not impressed to form elytral striae; the serial punctures are seemingly aligned in rows and the interserial punctures are somewhat irregularly distributed and moderately dense (in one or two rows, Fig. 9A, B). The general habitus and punctation of T. kappel are similar to those of T. arawak, T. canaima, and T. kolokoe. In T. arawak and T. canaima the interserial punctures are highly dense (forming two or three irregular rows, Fig. 3I). In T. kappel the coloration of pronotum and elytra gradually becomes paler (orange) towards the outer margins (Fig. 9A, B), and the legs are orange in color (Fig. 9C), whereas in T. kolokoe only the anterolateral margins of the pronotum are slightly paler and the legs are reddish brown in coloration (Fig. 9D-F). In addition, the serial punctures are equally impressed along the entire surface of the elytra in T. kappel (Fig. 9B) whereas in T. kolokoe the serial punctures become more impressed along the postero-lateral areas of the elytra (Fig. 9E).
Etymology. Noun in apposition. Named after the Kappel airstrip, the locality where the species has been collected.
Distribution. Known from two very closely situated localities adjacent to Kappel Airstrip, at the foot to Tafelberg Tepui in Suriname. See Fig. 13.
Life history. Series were collected from two seepage habitats: one vertical seepage on sandstone adjacent to a large waterfall, and the second from a small mostly horizontal seepage on sandstone seeping into an adjacent stream. See Fig. 16A Differential diagnosis. Tobochares kolokoe can be recognized by its strongly convex body in lateral view (Fig. 9E), accompanied by elytral punctation uniform in size and degree of impression, not impressed to form elytral striae; the serial punctures are seemingly aligned in rows and the interserial punctures are somewhat irregularly distributed and moderately dense (in one or two rows, e.g., Fig. 3H). The general habitus and punctation of T. kolokoe are similar to those of T. arawak, T. canaima, and T. kappel. In T. arawak and T. canaima the interserial punctures are highly dense (forming two or three irregular rows, Fig. 3I). In T. kolokoe only the anterolateral margins of the pronotum are slightly paler than the general coloration of the pronotum and the legs are reddish brown in coloration (Fig. 9E, F), whereas in T. kappel the coloration of pronotum and elytra gradually becomes paler (orange) towards the outer margins (Fig. 9B), and the legs are orange in color (Fig. 9C). In addition, the serial punctures become more impressed along the postero-lateral areas of the elytra in T. kolokoe (Fig. 9E), whereas in T. kappel the serial punctures are equally impressed along the entire surface of the elytra (Fig. 9B).
Description. Size and form: Body length 1.9 mm. Body elongate oval, strongly convex (Fig. 9E). Color and punctation: Dorsal and ventral surfaces of body dark brown, with prothorax (especially its anterolateral margins) slightly paler (Fig. 9D, E); mouthparts yellow (especially maxillary palps) to orange brown; antennae yellowish degree of impression (Fig. 6D), T. microps is similar to T. communis and T. anthonyae. Besides the shape of the eyes, T. microps, can be distinguished from T. communis by its relatively shallower punctation and smaller size (compare Fig. 6D to Fig 6A). From T. anthonyae, in which the dorsal punctation is also relatively shallow (Fig. 7A), T. microps can be recognized by the serial punctures seemingly longitudinally aligned and uniformly distributed, not impressed to form grooves (serial punctures clearly aligned in rows and slightly impressed, forming shallow longitudinal grooves in T. anthonyae; Fig. 7A).
Description. Size and form: Body length 1.6-1.7 mm. Body elongate oval, moderately convex (Fig. 6E). Color and punctation: Dorsal and ventral surfaces of body dark brown, with anterior and lateral margins of prothorax slightly paler (Fig. 6D, E); mouthparts yellow (especially maxillary palps) to orange; antennae yellowish brown; legs orange brown with paler (yellow) tarsi (Fig. 6F). Ground punctation on head, pronotum and elytra moderately marked. Head: Eyes in dorsal view with anterior margin slightly oblique (anteriorly directed), and outer margins nearly half the greatest length of eye, slightly bulging from outline of head (Fig. 2I); in lateral view, eyes not anteriorly emarginate (e.g., Fig. 2E). Thorax: Elytra with all punctures about the same size and degree of impression, all seemingly aligned in rows and uniformly distributed, not forming grooves (Fig. 6D). Metafemora mostly glabrous on anterior face (Fig. 6F). Elevation of mesoventrite forming a broad bulge (Fig. 6F). Metaventrite with distinct median, longitudinal, narrow glabrous area extending along posterior half (Fig. 6F). Abdomen: Abdominal ventrites uniformly and very densely pubescent. Aedeagus (Fig. 11I). Basal piece nearly 0.4 × the length of a paramere; greatest width of a paramere nearly 0.5 × greatest width of median lobe; outer margins of parameres uniformly weakly convex; apex of paramere rounded; median lobe roughly sagittate, narrow along apical third, rounded at apex; gonopore situated basad of midlength of median lobe.
Etymology. Named with the combination of the Latin words micro, meaning small, and ops, meaning eyes, highlighting the small eyes of the members of the species.
Distribution. This species is only known from the summit of Tafelberg Tepui, a low-elevation sandstone massif in the center of Suriname (Fig. 13).
Life history. Most specimens of this species were collected in seepage habitats by directly floating them out of saturated moss that was on the rock. Several specimens were collected in shallow pools on rock that were adjacent to seepages or streams. See Fig. 16C. Differential diagnosis. The general orange coloration with dark head of T. pemon is quite distinct among Tobochares, and particularly among members of the communis group. In addition, its elytral punctation is relatively unique, including all kinds of punctures being similar in size and degree of impression, with serial punctures aligned in rows, but not forming grooves, and with interserial punctures somewhat irregularly distributed in a single row (Figs 3F,7G,H). In addition, the median lobe of the aedeagus of T. pemon is unique, as it is uniformly broad throughout and apically broadly emarginate (Fig. 11E); the median lobe in other species typically narrows towards the apex and is usually rounded, except for T. luteomargo, which has an emarginated median lobe, but in this case the emargination is deep and very narrow (Fig. 11D).
Description. Size and form: Body length 1.7-1.8 mm. Body elongate oval, moderately convex (Fig. 7H). Color and punctation: Dorsal surfaces of body orange brown, with lateral margins of prothorax slightly paler (Fig. 7G, H); ventral surfaces of body (except prosternum) dark brown; mouthparts orange brown; antennae light brown; legs, including tarsi orange brown (Fig. 7I). Ground punctation on head, pronotum and elytra rather shallowly marked. Head: Eyes in dorsal view with anterior margin slightly oblique (anteriorly directed; Fig. 2D); in lateral view, eyes not anteriorly emarginate (e.g., Fig. 2E). Thorax: Elytra with all kinds of punctures similar in size and degree of impression; serial punctures aligned in rows, not forming grooves; interserial punctures somewhat irregularly distributed in a single row (Fig. 3F). Metafemora mostly glabrous on anterior face (Fig. 7I). Elevation of mesoventrite forming a low transverse carina (Fig. 7I). Metaventrite with distinct median, longitudinal, narrow glabrous area extending along posterior half (Fig. 7I). Abdomen: Abdominal ventrites uniformly and very densely pubescent (Fig. 7I). Aedeagus (Fig. 11E) with basal piece nearly 0.6 × the length of a paramere; greatest width of a paramere nearly 0.7 × greatest width of median lobe; outer margins of parameres straight and slightly converging along basal 2/5, then uniformly and widely convex; apex of paramere rounded; median lobe roughly rectangular, with wide and short medial emargination at apex; gonopore situated at apical fourth of median lobe.
Etymology. Noun in apposition. Named after the Pemon, an indigenous tribe that inhabits La Gran Sabana region in Venezuela, where Auyan Tepui is located.
Distribution. This species is known from the famous Auyan-tepui, which is also home to Angel Falls, the highest waterfall in the world. Collected at an elevation of 1700 m, this species is one of the relatively few water beetle taxa known from the "Pantepui Province", which comprises areas of the Guiana Shield which are greater than 1500 m in elevation (Fig. 13).
Life history. The only known series was collected in a flight intercept trap. Nothing further is known about the habitat or biology of this species. of the Guiana Shield region but includes one species in the Brazilian Shield as well. This is a signal that the geographic breadth of the genus is likely much larger, and we have still yet only cracked the surface of our taxonomic knowledge of this lineage.
Up to now, all species of Tobochares for which we have ecological data were associated almost exclusively with hygropetric habitats. These include isolated and seasonal rock seeps on inselbergs to wet rock habitats associated with waterfalls or the wet rock margins of streams and rivers. We report here for the first time the remarkable collection of a Tobochares species from both seepage as well as fully terrestrial habitats. We first collected Tobochares fusus from several riparian seepage habitats in the Brazilian state of Amapá, just a few kilometers from the border with French Guiana. The longest series was collected on a granite seepage adjacent to a small stream (Fig. 17A), while a second series was collected by washing a root mat that was growing over rock at the margin of a large stream (Fig. 17B). These collections were done in July, a traditionally wet season for the area. To our great surprise, during a separate trip to French Guiana in 2020, we found three specimens of T. fusus in rotting clusia fruits on dry forest floor, which we confirmed to be genetically identical to those from Brazil (Fig. 1). Within the Acidocerinae, species of the genus Quadriops were previously known to be terrestrial (see Girón and Short 2017), and indeed, we also collected a long series of Q. clusia Girón & Short, 2017 in the same rotting fruits together with T. fusus. The Clusia fruits were not near any source of water, and the collection was done in March during a dry period. We did collect in two streams with rocky substrate that were within 1 km of the rotten Clusia patch, but while we found many acidocerines, we did not find any Tobochares in these aquatic habitats. A nearby inselberg was also completely dry and had no exposed seeps or pools. Taken together, these collections suggest that Tobochares fusus is an ecologically vagile species, occurring in both hygropetric as well as fully terrestrial habitats. One possibility could be that the species moves to occupy rotting fruits in the dry season when other seepage habitats are rare or absent. However, more collection effort is required to support this hypothesis. by a Fulbright fellowship to AEZS and under SISBIO license 59961-1. We are grateful to the Office National des Forêts for the help provided during fieldwork in French Guiana. The expedition to Tafelberg was funded by grant #9286-13 from the National Geographic Society Committee for Research and Exploration to AEZS. This study was supported by US National Science Foundation grant DEB-1453452 to AEZS.