Notionotus shorti Queney, 2010: 133.

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

Notionotus shorti Queney, 2010: 133. syn. nov.

Type material examined.

Holotype (male): "♂ ", " Notionotus shorti /n. sp. HOLOTYPE/P. QUENEY descr.2010", "Guyana: Mazaruni-Potaro/District, Takutu Mountains,/ stream debris berlesed, 18-/XII-1983, leg. P.J. Spangler,/ W.E. Steiner & M. Levine" (USNM). Paratypes (8 exs.): same data as the holotype (8 exs., SEMC).

Additional material examined

(362 exs.). Brazil: Roraima State: Serra do Tepequém, 3°47.334'N, 61°42.570'W, 14.i.2018, leg. Short, Benetti, & Santana, small forested stream, BR18-0114-02A (1 ex., SEMC, DNA voucher SLE2377); Caroebe, Rio Caroebe , ca. 13 km NE of Caroebe, 00°54.786'N, 59°34.397'W, 150 m, 17.i.2018, leg. Short and Benetti, margins of sandy river, BR18-0117-04A (26 exs., INPA, SEMC, including DNA voucher SLE2330); Rio Jatapu nr. Usina de Jatapu , 00°50.939'N, 59°18.262'W, 145 m, 17.i.2018, leg. A. Short, marginal pools of river, BR18-0117-02A (1 ex., SEMC); Amajari, Rio Cocal , 3°44.135'N, 61°43.542'W, 237 m, 15.i.2018, leg. A. Short, clearwater creek, BR18-0115-01A (6 exs., SEMC, including DNA voucher SLE2374) . French Guiana: St. Laurent du Maroni ca. 15 km SW, Crique des cascades, 5.34662, -54.10539, 17 m, 4.iii.2020; leg. Short and Neff, stream margin, FG20-0304-02A (1 ex., SEMC); same data except leg. Short, leaf packs on rock, FG20-0304-02B (2 exs., SEMC, including DNA voucher SLE2339); same data except small rock pools in granite FG20-0304-02C (1 ex., SEMC); Carbet ONF Grillon, Piste Bélizon, Crique Grillon, 4.28219, -52.45163, 65 m, 11.iii.2020; leg. Short, rock pools by waterfall, FG20-0311-01C (2 exs., SEMC, including DNA voucher SLE2383); Crique à l’Est above Crique Eau Chire, 3.66383, -53.22193, 156 m, 10.xi.2016, leg. D. Post (1 ex., SEMC, DNA voucher SLE2113) . Guyana: Region 6: Upper Berbice, ca. 1 km, W basecamp, 4°09.143'N, 58°11.207'W, 170 m, 22.ix.2014, leg. Short, Salisbury, La Cruz, margins of creek, GY14-0921-03H (6 exs., SEMC); Upper Berbice , Basecamp 1, creek next to basecamp (upstream), 4.154817, -58.178616, 24.ix.2014, leg. Short, creek margins, GY14-0924-01A (1 ex., SEMC, DNA voucher SLE2108); Upper Berbice , Basecamp 1, 4°09.289'N, 58°10.717'W, 96 m, 22.ix.2014, leg. Short, Salisbury, La Cruz, GY 14-0924-01A (2 ex., SEMC) . Region 8: Upper Potaro Camp I (ca. 7 km NW Chenapau), 5°0.673'N, 59°38.358'W, 500 m, 14.iii.2014, leg. Short, Salisbury, La Cruz, clear water creek rapids, GY14-0314-01A (7 exs., SEMC); same data except 5°0.660'N, 59°38.283'W, 484 m, 11.iii.2014, leg. Short, Baca, Salisbury, La Cruz, clear water creek rapids, GY14-0311-04A (6 exs., SEMC, including DNA voucher SLE2368); same data except Potaro margin trail, 5°0.571'N, 59°38.202'W, 524 m, 11.iii.2014, leg. Short and Baca, leaf packs in rocky stream, GY14-0311-05A (1 ex., SEMC) . Region 9: Kusad, Mts. , Mokoro Creek , 2°48.531'N, 59°51.900'W, 170 m, 27.x.2013, leg. Short, Isaacs and Salisbury, main seepage area, GY13-1027-03B (2 exs., SEMC); same data except basecamp, leg. A. Short and Washington, on wet rocks, GY13-1024-03C (4 exs., SEMC); same data except 24.x.2013, leg. Salisbury, small rock pool with detritus, GY13-1024-03A (1 ex., SEMC); Kusad, Mts., basecamp area, 2°48.588'N, 59°51.931'W, 194 m, 23.x.2013, leg. A. Short, leaf packs in flow of creek, GY13-1023-02B (9 exs., CDBG, SEMC, including DNA voucher SLE2335); Kusad, Mts., Taraara Wao, 2°47.417'N, 59°53.986'W, 113 m, 28.x.2013, leg. Short, Isaacs and Salisbury, margin and isolated side pools, GY13-1028-01A (5 exs., SEMC, including DNA voucher SLE2107); N. Parabara, creek by basecamp (Bototo wau creek), 2°10.908'N, 59°20.306'W, leg. Short, 31.x.2013, stream margins, GY13-1031-01A (1 ex., SEMC, DNA voucher SLE2380) . Region Mazaruni-Potaro: Takutu Mountains , 6°15'N, 59°5'W, 2-14.xii.1983, leg. P.D. Perkins, stream ex. leaf packs and twigs (8 exs., SEMC) Suriname: Brokopondo District: Brownsberg Nature Park, near Capaci House , 4°56.934'N, 55°10.825'W, 460 m, 17.iii.2017, leg. A. Short, small stream, SR17-0317-01A (1 ex., SEMC); Leo Val/lrene Val return loop trail, 4.95069'N, -55.18599'W, 470 m, 18.iii.2017, leg. Baca and Johnson, stream, SR17-0318-01B (1 ex., SEMC); Leo Val, 4°57'16.08"N, - 55°11'26.82"W, 317 m, 19.iii.2017, leg. Short, leaf packs/detritus from behind waterfall, SR17-0319-01C (5 exs., SEMC); same data except SR17-0323-01C (6 exs., SEMC); same data except 23.iii.2017, leg. Baca, submerged woody debris, SR17-0323-01A (1 ex., SEMC); same data except side pools in creek, SR17-0323-01D (1 ex., SEMC); Witti Kreek, 4°55.674'N, 55°09.874'W, 84 m, 21.iii.2017, leg. Short and Baca, small side stream, SR17-0321-01D (2 exs., SEMC, including DNA voucher SLE2121); Brownsberg Nature Park, Mazaroni Val, 04°56.351'N, 55°12.108'W, 394 m, 5.viii.2012, leg. Short, Maier, Mcintosh, forested waterfall and stream, SR12-0805-01A (22 exs., NZCS, SEMC); Brownsberg Nature Park, 04°57.268'N, 55°11.447'W, 317 m, 4.viii.2012, leg. Short, Maier, Mcintosh, forested waterfall and stream, SR12-0804-02A (21 exs., SEMC); Brownsberg Nature Park, 04°56.871'N, 55°10.911'W, 462 m, 4.viii.2012, leg. Short, Maier, McIntosh, SR 12-0804-01A (2 exs., SEMC including SLE505 and SLE506) . Sipaliwini District: Kabalebo Nature Resort: Bwkw rapids, 4.40041°N, 57.24658°W, 90 m, 9-10.9 iii.2019, leg. Short and class, large isolated muddy pool by river, SR19-0309-02A (1 ex., SEMC); Moi Moi creek , 4.42313°N, 57.19198°W, 104 m, 10-14.iii.2019, leg. Short and class, rock and detrital pools along creek, SR19-0310-01A (3 exs., SEMC); same data except leg. Short and Baca, small seeps, SR19-0310-01F (10 exs., SEMC); same data except leg. Short, margin of detrital pool in drying creekbed, SR19-0310-01G (5 exs., SEMC); same data except leg. Short, Baca and class, SR19-0310-01J (1 ex., SEMC); same data except leg. Baca, margin of stream pool with root mats, SR19-0310-01L (5 exs., SEMC); same data except leg. Short and class, SR19-0310-01M (10 exs., SEMC, including DNA voucher SLE1799); same data except Leg. S. Baca, upstream riparian habitats, SR19-0310-01N (2 exs., SEMC); Sand Crk, 4.38476°N, 57.24636°W, 72 m, 13-15.iii.2019, leg. Short and Baca, upper marginal pool along river, SR19-0313-01D (2 exs., SEMC); Charlie Falls , 4.38302°N, 57.21161°W, 174 m, 11.iii.2019, leg. Short and class, rock pools in creekbed, SR19-0311-01A (39 exs., NZCS, SEMC, including DNA voucher SLE1811); same data except leg. Short, seepage, SR19-0311-01B (7 exs., SEMC); Sipaliwini Savanna Nature Res. 4- Brothers Mts , 2°00.342'N, 55°58.149'W, 337 m, 31.iii.2017, leg. Short and Baca, clear water stream sandy with detritus, SR17-0331-01B (31 exs., SEMC, including DNA Voucher SLE2114); same data except leg. Baca, small rocky creek, SR17-0331-01A (1 ex., SEMC); Raleighvallen Nature Reserve , Fungu Island , 4°43.459'N, 56°12.658'W, 30 m, 14.iii.2016, leg. A. Short, isolated river margin pools, rocky bottom, SR16-0314-01E (1 ex., SEMC); Coppename Rvr-Voltzberg trail, 15.iii.2016, leg. A. Short, small sandy stream, SR16-0315-02A (1 ex., SEMC); Lolopaise Area , 4°42.48'N, 56°13.15908'W, 24 m, 18.iii.2016, leg. Short et al., intermittent stream margins, flotation, SR16-0318-01D (1 ex., SEMC); Brownsberg Nature Park, 04°56.871'N, 55°10.911'W, 462 m, 4.viii.2012, leg. Short, Maier, Mcintosh, forested stream with lots of detritus, SR12-0804-01A (8 exs., SEMC); Raleighfallen Nature Reserve , trail to Raleighfallen, 04°42.480'N, 56°13.159'W, 24 m, 27.vii.2012, leg. Short, Mcintosh and Kadosoe, creek margins, SR12-0727-03A (22 exs., SEMC, including DNA voucher SLE2394); same data except leg. C. Mcintosh, detrital pools near creek in forest, SR12-0727-03D (1 ex., SEMC); Raleighvallen Nature Reserve Voltzberg Station , 04°40.910'N, 56°11.138'W, 78 m, 9.vii.2012, leg. Short, Maier, McIntosh, and Kadosoe, stream margins, SR12-0729-02A (1 ex., SEMC, DNA voucher SLE2389); Raleighfallen Nature Reserve , Voltzberg trail, 04°40.910'N, 56°11.138'W, 78 m, 30.vii.2012, leg. C. Maier and V. Kadosoe, margin of stream, SR12-0730-01A (1 ex., SEMC); Raleighfallen Nature Reserve , Fungu island , 04°43.459'N, 56°12.658'W, 30 m, 1.viii.2012, leg. Short, Maier, Mcintosh and Kadosoe, small creek, SR12-0801-01B (2 exs., SEMC); Camp 2, on Sipaliwini District, CI-RAP Survey, 2°10.973'N, 56°47.235'W, 210 m, 29-30.viii.2010, leg. Short and Kadosoe, Inselberg, SR 10-0829-01A (2 exs., SEMC); Camp 1, Upper Palumeu , CI-RAP Survey, 2.47700°N, 55.62941°W, 275 m, 11.iii.2012, leg. Short and Kadosoe, around waterfall, SR12-0311-03A (2 exs., SEMC); Camp 3, Wehepai, 2°21.776'N, 56°41.861'W, 237 m, 4-6.ix.2010, leg. Short and Kadosoe, sandy forest creek, SR10-0904-01A (36 exs., SEMC, including DNA voucher SLE2375) . Venezuela: Bolívar State: Piedra de la Virgen , 6°5'14.1"N, 61°23'55.8"W, 400 m, 31.vii.2008, leg. A. Short M. García, L. Joly, small forest stream, AS-08-056 (7 exs., SEMC, including DNA voucher SLE2378) . Amazonas State: Tobogan de la Selva , 5°23.207'N, 67°36.922'W, 125 m, 14.i.2009, leg. A. Short, clumps of wet leaves on rock, VZ09-0114-01D (6 exs., MIZA, SEMC, including DNA voucher SLE2366) .

Differential diagnosis.

The general coloration of Notionotus dilucidus is similar to N. giraldoi , N. mexicanus , and N. tricarinatus and these species are very difficult to differentiate with external characters alone. However, the shape of the aedeagus in N. dilucidus is quite distinct: the outer and inner margins of the parameres are sinuate, the apex of the parameres presents an indentation in which the depth can vary from very deep, slightly deep, or almost not distinguishable and pointing outwards (Fig. 5A-J ).

Description.

Size and form: Body length 1.6-1.8 mm. Body form elongate oval, moderately convex in lateral view (e.g., Fig. 2D ). Color and punctation: Dorsally yellow to pale brown, head mostly yellow and frons pale brown; pronotum paler than elytra, with two small black round spots along posterior margin (e.g., Fig. 2D ). Ventrally brown; maxillary palps and antennae yellow (antennal club slightly darker), mouth parts and legs pale brown. Clypeus and labrum with dense, fine, and weakly impressed ground punctation (punctures separated by 1-2 × their width); pronotum and elytra with 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, pointing anteriorly and acute. Elevation of mesoventrite with one transversal ridge, elevated medially, lateral sides concave; longitudinal ridge sharp, the point where the two ridges merged rounded and obtuse (Fig. 10A ); elevation flat in lateral 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, medial region patch drop-shaped; anterior margin extending to mesoventrite elevation. Metafemora densely covered with hydrofuge pubescence on basal three-quarters (e.g., Fig. 2E ). Abdomen: Abdominal ventrites very densely pubescent. Aedeagus (Fig. 5A ) basal piece nearly the same length of a paramere. Base of the parameres slightly narrower than the base of the median lobe; outer margins sinuate, tapering almost reaching the apex, inner margins sinuate, apex of the parameres slightly bending outwards, rounded in the outer margin with an indentation in the inner margin (the depth of the indentation varies, Fig. 5A-J ). Median lobe nearly as long as the parameres or a bit longer, broad at the base and gradually narrowing to the apex, apex of the median lobe rounded.

Variation.

There is significant variation in the apex of the parameres of the aedeagus. The paramere tip is weakly sclerotized, as evidenced by its very pale to white appearance in cleared specimens (e.g., Fig. 5A-J ). This tip varies from nearly evenly rounded (e.g., Fig. 5D, G ) to possessing some level of indentation on the inner margin (e.g., Fig. 5A, H ). Although this variation seems in part to be real, it also seems to be partly caused by artificial distortions; for example, the weakly sclerotized apex may become indented or inflated depending on the state of the genitalia during preparation. This would explain why there is a large variation in form as well as why the tip appears to be exhibit subtly asymmetry between parameres (e.g., Fig. 5C, F ).

Distribution.

This species is widely distributed throughout the Guiana Shield region, from Tobogán de la Selva in Venezuela east to the coast of French Guiana (Fig. 15 ). Reported from Suriname in Short and Kadosoe (2011) and Short (2013; as N. shorti ) and from Guyana as Notionotus sp. B in Short et al. (2018).

Life history.

This species is the most common and abundant species of the genus in the Guiana Shield region and is frequently collected in leaf packs or along the margins of forested streams. They are typically found in streams that are lined with detritus and have rocky or sandy substrates. Although some specimens have been collected in seepage-like habitats or adjacent to seepages, this does not seem to be a primary or favored habitat for this species.

Remarks.

Queney (2010) described N. dilucidus based on specimens from several closely situated localities in French Guiana, and N. shorti based on a long series of specimens from a single collecting event in Guyana. The primary feature used to separate the two taxa was the apex of the parameters, which was given as "parameres apically shortly curved outwards" in N. dilucidus and "parameres apically almost straight" in N. shorti . We examined material from the type series of both species and confirmed there are notable differences in the paramere shape. If we only had access to the specimens that Queney (2010) examined and no other data, we also would have very likely concluded they were different species and described them as such. However, as we examined recently collected specimens from numerous other localities in the eastern Guiana Shield, we observed quite a bit of variation in the shape of the parameres that encompassed the forms present in N. dilucidus and N. shorti . In some cases, we noticed variation in this feature even among specimens from the same series. Additionally, the apex of the paramere even occasionally appears slightly asymmetrical in some dissections (e.g., Fig. 5F, J ).

To help interpret these morphological observations, we sequenced 22 specimens that span the entire width of the Guiana Shield, including specimens from Venezuela, Brazil, Guyana, Suriname, and French Guiana. These specimens also represented a range of paramere form diversity. In general, we found little meaningful molecular divergence among these populations (Fig. 1 ) and these differences were not correlated to observed variations in the paramere apex. Therefore, we here consider N. shorti as a junior subjective synonym of N. dilucidus .

Among all sequenced specimens, the maximum pairwise divergence in the gene COI was 6.0%. Although this is on the higher end of intraspecific divergence observed in hydrophilids, it is seen in some taxa (see Short and Girón 2018; Smith and Short 2020). Additionally, given that its geographic range spans 1500 kilometers, it is not surprising to see such divergences. The two Venezuelan populations (from Tobogán de Selva in Amazonas State and the Escalera region of Bolívar State) were the most genetically distinct and sister to the more eastern populations. Indeed, with these samples removed, the maximum intraspecific divergence among remaining specimens drops to just 3.8%. However, we did not observe any significant morphological differences from these Venezuelan populations and therefore consider them to be part of a broader definition of N. dilucidus .

As both N. dilucidus and N. shorti were proposed in the same work ( Queney 2010), we use our authority as first revisors (ICZN article 24.2.2) to give precedence to N. dilucidus as the valid name for this species.

Figures

Figure 1. Maximum likelihood phylogeny of Notionotus spp. inferred from COI and 28 S sequence data. Extraction numbers are given next to each terminal name (see Table 1).

Figure 2. Habitus and labels of Notionotus spp.: N. liparus (holotype): A dorsal view B ventral view C labels; N. mexicanus (holotype): D dorsal view E ventral view F labels; N. rosalesi (holotype): G dorsal view H ventral view I labels.

Figure 5. Aedeagi of Notionotus dilucidus A N. dilucidus (paratype) B N. shorti (paratype) C-J N. dilucidus C specimen from Roraima, Brazil D specimen from Guyana E specimen from French Guiana F specimen from Suriname G specimen from Roraima, Brazil H specimen from Bolivar State, Venezuela I specimen from Amazonas State, Venezuela J specimen from Suriname.

Figure 10. Mesoventral process of Notionotus spp. A N. dilucidus B N. tricarinatus C N. insignitus D N. bicolor. Red marks pointing to transverse ridge in A-D blue marks pointing to second transverse ridge in C, D.

Figure 15. Distribution map of Notionotus spp.