Globulosis hemisphericus García, 2001

Short, Andrew Edward Z., García, Mauricio & Girón, Jennifer C., 2017, Revision of the Neotropical water scavenger beetle genus Globulosis García, 2001 (Coleoptera: Hydrophilidae: Acidocerinae), Zootaxa 4232 (2), pp. 271-281 : 275-277

Globulosis hemisphericus García, 2001

Figs. 2 A–C, 3A, 4, 7B–E, 8, 9.

Globulosis hemisphericus García, 2001: 156 .

Globulosis hemisphaericus García : Short & Hebauer, 2006: 338. (incorrect subsequent spelling) Globulosis sp. 1: Short & Kadosoe, 2011: 89; Short 2013: 87.

Type material examined. Holotype (male): “ Venezuela, Bolívar / Mcpio [Municipio] Sifontes / Tierra Blanca— Pantano / 23/10/99 ”, “ Col.:/ Julio Gonzales / Jesus Berti / Edith Navarro ”, “ Holotipo [male symbol]/ Globulosis / hemisphericus / Dcrip. M. García, 1999” ( MALUZ).

Additional material examined (50 exs.). BRAZIL: Amazonas: Manaus, PBBFF, Highway BR 174, km 72, Faz. Dimona, Igarapé (Cuieiras) Capoeira Vismia , 22.x.2001, leg. Nessiman (2 exs., DZRJ) . Pará: Rio Xingu Camp , ca. 60 km S. Altamira, stream on left branch of trail 1, 14.x.1986, leg. P.J. Spangler & O. Flint (3 exs., USNM) . GUYANA: Region 6: Upper Berbice , ca. 1 km W. Basecamp 1, 105 m elev., small sandy stream, 21.ix.2014, leg. Short, GY 14-0921-03A (2 exs., SEMC, voucher SLE1075) ; Upper Berbice, ca. 1 km W. Basecamp 1, 105 m elev., small detrital side pools, 22.ix.2014, leg. Short, GY 14-0921-03G (1 ex., SEMC) ; Upper Berbice, ca. 1 km W. Basecamp 1, 105 m elev., 22.ix.2014, leg. Short, GY 14-0921-03H (2 exs., CBDG, SEMC) ; Upper Berbice, Basecamp 1, ca. 1 km S of camp along mammal transect, 109 m elev., dip netting along bank with roots, 25.ix.2014, leg. Short, GY 14-0925-01A (1 ex., SEMC) . Region 8: Chenapau village , trail between airstrip and town, 427 m, large pool with lots of detritus, 14.iii.2014, leg. Short, GY 14-0314-03A (1 ex., SEMC; voucher SLE1074). Region 9: Parabara, trail to mines , 250 m elev., leg. Short, Isaacs, Salisbury, GY 13-1102-01 A (1 ex., SEMC; voucher SLE972). Region 10: Dubulay Ranch, Warniabo River , 10.iv.1994, leg. P.J. Spangler & R. Perry (1 ex., USNM) ; Dubulay Ranch, Aramatani River , 170 m elev., 17.iv.1995, leg. P.J. Spangler (7 exs., USNM) ; Dubulay Ranch, Warniabo River , edge of stream, 18.iv.1995, leg. P.J. Spangler & R. Perry (1, USNM) ; CEIBA, 40 km S. Georgetown, 13.iv.1994, leg. P.J. Spangler (1 exs., USNM). SURINAME: Brokopondo: Brownsberg Nature Park, Leo Val , 4.viii.2012, leg. Short, Maier, & McIntosh, forested waterfall and stream, SR12-0804-02A (1 ex., SEMC) . Marowijne: East-West Highway , 23 km W. Moengo, 29 m elev., 4.iii.2012, leg. Short & Kadosoe, blackwater swamp SR12-0304-05A (2 exs., SEMC) . Sipaliwini: Kutari River, Camp 1, 228 m elev., forest stream, 20.viii.2010, leg. Short & Kadosoe, SR 10-0820-01A (10 exs., NZCS, SEMC; voucher SLE973); Camp 3, Wehepai , 237 m elev, leg. Short & Kadosoe, sandy forest creek, SR10-0904-01A (1 ex., SEMC); Raleighvallen Nature Reserve, Lolopasie Area , 24 m elev., 27.vii.2012, leg. Short, McIntosh, & Kadosoe, stream margin using flotation, SR12-0727-03A (4 exs., SEMC, NZCS); Raleighvallen Nature Reserve, Voltzberg Station , 78 m elev., stream margins, 29.vi.2012, leg. Short, Maier, McIntosh, & Kadosoe SR 12-0729-02A (1 ex., SEMC, voucher SLE970); Kasikasima, Camp 4 (low) , 200 m elev., sandy creek, 20.iii.2012, leg. Short, SR12-0320-02A (4 exs., SEMC; voucher SLE416); Central Suriname Nature Reserve, Talfelberg Summit, near Augustus Creek Camp, 600 m elev., 22.viii.2013, leg. Short & Bloom, SR 12-0822-02B (1 ex., SEMC) ; same data but SR13-0822-01A (1 ex., SEMC; voucher SLE971).

Differential diagnosis. The curved outer margins of the parameres ( Fig. 7 B–E) and dark brown dorsal coloration ( Fig. 2 A) serve to distinguish this species from G. flavus , which has parallel-sided parameres and is pale in coloration.

Description. Total body length 2.0– 2.3 mm. Dorsal coloration brown to very dark brown ( Fig. 2 A). Thoracic and abdominal venter dark brown ( Fig. 2 C). Maxillary palps uniformly yellow ( Fig. 3 A). Aedeagus ( Fig. 7 B–E) with basal piece short, less than one-third the length of the parameres; outer margins of parameres distinctly curved inward. Median lobe broad, gradually tapering from the base to the apex into a blunted point, apex even with to slightly longer than the apex of the parameres; gonopore situated in the middle to apical third.

Variation. The dorsal coloration varies from a medium to very dark brown; we have not observed any nonteneral specimens that are as pale in color as G. flavus . The aedeagus also exhibits some variation with regard to degree of curvature of the outer margins of the parameres (may be weakly to strongly inwardly curved along their entire length), and the relative extension of the median lobe (may be even with the apex of the parameres or extending beyond them). The opening of the gonopore also varies in position, from being situated in the middle of the median lobe to being located more apically (compare Fig. 7 C with 7D and 7E). There was no clear correspondence in these characters with geography or the genetic groups found in Fig. 1 .

Distribution. Venezuela (Bolívar), Guyana, Suriname, Brazil (Amazonas, Pará).

Biology. All known collecting events were from lotic habitats, primarily along the margins of small to medium sized streams and small rivers (e.g., Fig. 7 B–D). Most of these habitats had at least some sand substrate and decaying organic matter such as leaf litter. It has been collected on the summit of one low-elevation Tepui (Tafelberg) in Suriname.

Remarks. The aedeagus of the holotype ( Fig. 4 ) had been mounted on a slide under a coverslip and stored vertically. When we observed the slide, the genitalia had migrated out from under the coverslip to its margin and had become distorted. We soaked the slide in water and dismounted the aedeagus, but it was in very poor condition. What remains has been placed in glycerin in a microvial and pinned beneath the specimen.

The correct original spelling of the specific epithet, hemisphericus , is an incorrect transliteration of “ hemisphaericus ”. This type of spelling error is uncorrectable (ICZN 32.5), thus the correctly transliterated form listed in Short & Hebuaer (2006) is to be considered an incorrect subsequent spelling.

Figures

FIGURE 1. Maximum likelihood phylogeny of 10 populations (mapped at right) of Globulosis based on COI sequences (yellow squares = G. flavus; red circles = G. hemisphericus).

FIGURE 2. Habitus of Globulosis spp. G. hemisphericus (from Suriname): (A) dorsal, (B) lateral, (C) ventral; G. flavus (paratype): (D) dorsal, (E) lateral, (F) ventral. Scale bar 1 mm.

FIGURE 3. Head in frontal view of Globulosis spp. (A) G. hemisphericus, (B) G. flavus. Scale bar: 0.5 mm.

FIGURE 4. Holotype of G. hemisphericus. (A) dorsal view, (B) ventral view, (C) labels.

FIGURE 7. Aedeagus of Globulosis spp. (A) G. flavus sp. n. (holotype), (B) G. hemisphericus, reproduced from García, 2001, (C) G. hemisphericus from the upper Berbice, Guyana, (D) G. hemisphericus from Manaus, Brazil, (E) G. hemisphericus from Raleighvallen Nature Reserve, Suriname. Scale bar 0.05 mm.