Canthysellus sipaliwini Baca and Toledo

Baca, Stephen M. & Toledo, Mario, 2015, CanthysellusBaca and Toledo (Coleoptera: Noteridae: Noterini), a New Genus of Burrowing Water Beetle from South America, The Coleopterists Bulletin 69 (3), pp. 477-488 : 485-486

Canthysellus sipaliwini Baca and Toledo , new species

( Figs. 2 , 9 )

Type Locality. Suriname, Sipaliwini District, Kutari River .

Type Material. Holotype (male): “ SURINAME: Sipaliwini District / 2°10.521′N, 56°41.861′W, 228 m / Camp 1, on Kutari River ; leg. Short / & Kadosoe; forest stream/ 20.viii.2010, SR10- 0820-01A/ 2010 CI-RAP Survey” [printed], “SEMC0913912/ KUNHM-ENT” [barcoded label], “Photo Voucher/ PV__/ Short Lab – KU NHM” [green label, printed], “ HOLOTYPE / Canthysellus / sipaliwini / Baca & Toledo, 2015” [red label, printed] ( NZCS) . Paratypes (11 specimens): “ SURINAME: Sipaliwini District / 2°21.776′N, 56°41.861′W, 237 m /, Camp 3, Wehepai, leg. Short &/ Kadosoe, sandy forest creek/ 4–6.ix.2010, SR10- 0904-01A/ 2010 CI-RAP Survey” [printed] “SEMC0930390/ KUNHM-ENT” [barcoded label] (1 ex. SEMC); “ SURINAME: Sipaliwini District / 2°10.521′N, 228 m / Camp 1, on Kutari River, leg. Short / & Kadosoe, forest stream/ 20.viii.2010, SR10-0820-01A/ 2010 CI-RAP Survey” [printed] “SEMC0913977/ KUNHM-ENT”, “SEMC0913853/ KUNHM-ENT” and “SEMC0914003/ KUNHM- ENT” [all barcoded labels] (1 male; 3 females exs. SEMC); “ SURINAME: Sipaliwini District / 2°10.521′N, 56°47.244′W, 228 m / Camp 1, on Kutari River / Short & Kadosoe, forest swamp/ 22.viii.2010, SR10-0822-02A/ 2010 CI-RAP Survey” [printed] “SEMC0912971/ KUNHM- ENT” [barcoded label] (1 male ex. SEMC); “ SURINAME: Sipaliwini District / 2°10.973′N, 56°47.235′W, 210 m / Camp 2, on Sipaliwini River/ Short & Kadosoe, forest creek/ 31.viii. 2010, SR10-0831-01A/ 2010 CI-RAP Survey” [Printed] “SEMC0914696/ KUNHM-ENT” [Barcoded label] (1 female ex. SEMC); “ SURINAME: Sipaliwini District / 02°22.259′N, 56°41.227′W, 229 m / Camp 3: Werehpai, SE Kamala/ detrital pools in dense forest/ 3–5.ix.2010, leg. Short & Kadosoe/ CI-RAP Survey, SR10-0903-02A” [Printed] “ SEMC0912303/ KUNHM-ENT”, “ SEMC 0912212 / KUNHM-ENT ” and “SEMC0912064/ KUNHM-ENT” [all barcoded labels] (3 females exs. SEMC); ‘ SURINAME: Sipaliwini District / N 2.47700°, W 55.62941, 275 m / Camp 1, Upper Palumeu / leg. A. Short, Flight Intercept Trap/ 10–16.iii.2012, SR12- 0310-TN1/ 2012 CI-RAP Survey” [Printed]

“SEMC1089356/ KUNHM-ENT” [Barcoded label] (1 male ex. SEMC). All paratypes with “PARA- TYPE/ Canthysellus / sipaliwini / Baca & Toledo, 2015” [blue label, printed].

Diagnosis. Canthysellus sipaliwini is distinguishable from other members of the genus by the following combination of characters: (a) metatibia as in Fig. 6 , with distinctly spaced line of moderately stout setae on inner margin, metatarsomere I with similar row of setae; (b) line of setae on prosternum as in Fig. 4a, 4b , with 5–9 setae, extending laterally to or past anterolateral margins of prosternal process, usually discontinuous, reduced or more widely spaced medially; (c) head very dark at base and between eyes ( Fig. 2 ); (d) size larger, 3.00– 3.30 mm; (e) aedeagus as in Fig. 9a–f ; median lobe expanded ventrally and attenuated to a point apically in lateral aspect; left lateral lobe very broad with dense tuft of setae produced subapically on inner surface; setae extending to or only just beyond lobe margin ( Fig. 9d ).

Diagnosis. Canthysellus sipaliwini is very similar to C. buqueti . Externally, it is most easily distinguished by its larger size and the darkened, nearly black head between the eyes and at its base ( Fig. 2 ). Canthysellus buqueti is smaller, with the head only weakly infuscate at the base and between the eyes. The aedeagi of these species are also similar, but the median lobe of C. sipaliwini is apically more elongate and attenuate than that of C. buqueti ( Fig. 9a–c ), and the left lateral lobe is broader, with a tuft of setae that extend only to, or slightly beyond, the dorsal margin ( Fig. 9d ). That of C. buqueti is not as broad and has setae that extend well beyond the dorsal margin ( Fig. 8d ). The left lateral lobes are the most distinguishable characters of the aedeagi of these two species.

Description. Holotype. Male. Color and appearance: Shiny, elytra superficially iridescent. Maculate, bicolorous; color of head brownish yellow with base and area between eyes strongly infuscate, nearly black; color of pronotum brownish yellow; color of elytra very dark brown, nearly black; color of maculae brownish yellow, similar to color of pronotum. Color of venter dark brownish yellow, with noterid platform and sutures darker, brown; color of legs slightly lighter than venter. Maculae as in Fig. 3 , each elytron with 3 spots: 1 slightly elongate, as a short, transverse band in distal third of elytron, and 2 laterally oriented just anterior to midlength of elytron, with medial spot near elytral suture, anterolaterally oblique and sometimes broken into 2 smaller spots, and lateral spot submarginal, oval. Thorax: Pronotum with lateral bead very broad, 1.73X width of antennomere VII. Prosternal disc similar to Fig. 4b ; with transverse line of 8 stiff setae, widely separated at median, appearing as 2 smaller lines or tufts anterior to lateral margins of prosternal process. Prosternal process and noterid platform setose; setae short, stiff, evenly distributed and produced from distinct punctures (as in Fig. 4 ). Metatibia as in Fig. 6 , with row of ca. 9 evenly spaced setae on inner margin ( Fig. 6a ), additional few setae produced submarginally on posterior surface near mediodistal angle; metatarsomere I with similar row of 4–5 setae on inner margin ( Fig. 6a ). Abdomen: Aedeagus as in Fig. 9a–e ; median lobe strongly curved, ventrally divided by large ventral groove running from base to apex, twisting at apex, left lateral side expanded ventrally and attenuate to acute apex ( Fig. 9a, c ); left lateral lobe very broad, curved slightly inward towards median lobe, ventral margin broadly curved, dorsal margin straight, with dense tuft of setae subapically produced, setae short, only barely extending past lobe margin ( Fig. 9d ). Right lateral lobe broad, subtriangular, ventrally rounded ( Fig. 9e ). Measurements: Holotype: L = 3.00 mm; TL = 3.35 mm; GW = 1.80 mm; HW = 0.95 mm; EW = 0.55 mm; PntB = 0.12 mm; AntVII = 0.07 mm; L/GW = 1.65, HW/EW = 1.68; PntB/AntVII = 1.73. Paratypes: L = 3.00– 3.30 mm, males = 3.00– 3.10 mm, females = 3.10–3.30 mm; TL = 3.35–3.50 mm; GW = 1.80–1.95 mm; HW = 0.95–1.05 mm; EW = 0.55–0.60 mm; PntB = 0.11– 0.13 mm; AntVII = 0.06–0.07 mm; L/GW = 1.62–1.72; HW/EW = 1.63–1.74; PntB/AntVII = 1.63–1.88.

Variation. Members of C. sipaliwini vary most noticeably in the prominence of the maculae on the elytra. Though most specimens appear as in Fig. 2 , the maculae of some specimens are reduced to more slender bands or spots, though orientation remains consistent. Very little variation was observed in color, though some were very slightly darker or lighter than holotype. The setae of the prosternum ( Fig. 4 ) varied slightly in number and spacing. The number of setae ranges ca. 6–9 in total, and though the spacing of these setae most commonly appears as in Fig. 4b , with the series widely discontinuous medially, a few specimens were observed to have these setae less widely spaced. Additionally, a few specimens were observed to have this spacing between setae filled by a very small, lone seta. Inconsequential variation in the number and placement of setae were also observed elsewhere, e.g., the metatibia. Finally, members of this species display variation in size. Females are notably more robust than males.

Biology. Canthysellus sipaliwini was collected in small numbers from a variety of aquatic habitats in forested areas, including creeks, streams, detrital pools, and swamps ( Fig. 13a ). One specimen was collected in a flight intercept trap.

Distribution. Canthysellus sipaliwini is known only from southwestern Suriname, near the Guyanese boarder ( Fig. 12 ).

Etymology. The specific epithet is the name of the type locality. It is treated as a noun in apposition.

Figures

Figs. 1–3. Canthysellus species, dorsal and lateral habitus. 1) C. buqueti, male; 2) C. sipaliwini, holotype, male;

Figs. 8–10. Canthysellus species, aedeagi. 8) C. buqueti, Suriname; 9) C. sipaliwini, holotype, Suriname; 10) C. peruanus, paratype, Peru. a = median lobe, left lateral aspect, b = median lobe, dorsal aspect, c = median lobe, right lateral aspect, d = left lateral lobe, e = right lateral lobe. Scale bars = 0.25 mm.

Figs. 6–7. Canthysellus species,hind legs.6) C.buqueti, male, a = setae of inner margin of metatibia, b = posterior metatibial spur, serration is diagnostic of the genus; 7) C. peruanus, paratype, male, a = setae of inner margin of metatibia. Scale bars = 0.25 mm

Figs. 4–5. Canthysellus species, pro- and metasterna and metacoxae (noterid platform) with studies of prosternal setae. 4) C. buqueti, male, a and b = variation of prosternal setae; 5) C. peruanus, paratype, male, a = enlarged view of prosternal setae. Scale bar = 0.5 mm.

Fig. 13. Habitats of Canthysellus species. a) Type locality of C. sipaliwini, Suriname: Sipaliwini District, stream near the Kutari River, collecting event SR13-0816-02A, b) Example habitat of C. buqueti; Suriname: Sipaliwini District, summit of Tafelberg Tepui, collecting event SR13-0816-02A.

Fig. 12. Distribution map of Canthysellus species.