Oiovelia Drake & Maldonado-Capriles, 1952

Rodrigues, Higor D. D., Melo, Alan Lane De & Ferreira-Keppler, Ruth L., 2014, Taxonomic revision of the Neotropical genus Oiovelia (Hemiptera: Heteroptera: Veliidae), Acta Entomologica Musei Nationalis Pragae (suppl.) 54 (1), pp. 65-98 : 71-72

Oiovelia Drake & Maldonado-Capriles, 1952

Type-species: Oiovelia cunucunumana Drake & Maldonado-Capriles, 1952 , by original designation.

Oiovelia Drake & Maldonado-Capriles, 1952: 51 (original description).

Redescription. Polymorphism within the genus is common, with macropterous ( Figs 26–28 ) and apterous ( Figs 22–23 ) forms. General body color usually brownish ( Fig. 23 ), varying from dark brown, almost black ( Figs 55–58 ), to yellow ( Figs 32–34 ), with whitish pruinose areas. Body length usually between 3.00 and 4.30 mm. Body without modified setae similar to minute dark spines. Head elongated and deflected in front of eyes ( Figs 78–80 ), with a pair of oblique punctations on posterior region, near inner margin of eyes ( Figs 1–2 ). Eyes globose, separated by a distance greater than eye width, located on posterior portion of the head, adjacent to anterior margin of pronotum. Ocular setae always present, with a pair on each eye. Rostrum reaching mesocoxa ( Fig. 25 ), with segment III distinctly longer than others.

Pronotum in both apterous and macropterous forms long, covering meso- and metanotum, with lateral area of anterior lobe with long dark setae, and a row of rounded punctations adjacent to anterior margin; posterior lobe covered by same punctations, with posterior angle rounded ( Fig. 2 ); whitish pruinose areas usually present on anterior lobe and/or posterior lobe ( Figs 29 , 54 ). Apterous form with humeral angles not elevated. The contrary occurs in the macropterous form, with humeral angles slightly elevated, and usually dark brown fore wings reaching genital segments; the two basal cells smaller than the two apical cells; when closed, forming a pair of basal maculae near humeral angles, varying from whitish ( Fig. 26 ) to yellowish ( Fig. 27 ); in addition to these maculae, rest of wing with whitish pruinosity, which can be uniform and covering almost entire wing ( Figs 24 , 26–27 ) or well delimited between cells ( Figs 47–49 , 50–51 ). Propleura, mesopleura, and prosternum with rounded punctations. Intersegmental region between meso- and metasternum always with two pairs of small tubercles medially ( Fig. 5 ). Legs without modifications or spines; tarsi three-segmented; tarsomeres I–II short, III longer and wider than previous; tarsomere II of mid leg usually at most 2× longer than I; tarsomere III expanded, with lateral margins divergent; pretarsus composed of a pair of symmetrical, falciform claws and a pair of setae-like aroliae ( Fig. 9 ); these structures are inserted in a median cleft that divides tarsomere III into two lobes, where external one is twice the size of the internal one. Male presents a grasping comb on inner margin of protibia, absent in female ( Figs 3–4 ).

Abdomen in both sexes without modifications, usually with whitish pruinose areas laterally; posterior angle of last connexival segment not developed ( Figs 78–80 ). Males: connexiva horizontal to slightly elevated; apterous form with six visible tergites ( Fig. 32 ); sternite VII without projections or lobes on posterior margin ( Fig. 34 ); pygophore simple, with pilosity on posterior half; proctiger with an acute projection ( Fig. 46 ), spines ( Fig. 37 ) or without modifications ( Fig. 40 ); parameres symmetrical, elongated and slightly curved ( Figs 71–77 ). Females: connexiva elevated; apterous form with seven visible tergites, generally with part of the connexives reflected over abdomen ( Figs 23 , 33 , 56 ); proctiger small, globose; first gonocoxa plate-like ( Figs 78–80 ).

Differential diagnosis. In Oiovelia , specimens with high variation of color and pruinosity are common. Also, some species are morphologically very similar, differing basically in the color and male genitalia. For this reason, even when having a few specimens, it is necessary to examine male characters to confirm the species identification. However, species of the genus usually have gregarious behavior, and are consequently easily collected in large numbers. In foam masses, where these insects preferably live ( Figs 16–19 ), it is common to observe several couples in copulation, and nymphs of all instars. When compared with other Neotropical veliids, the genus Oiovelia has the most active flight behavior, and the migration of specimens between the foam masses is frequently observed in the field. In addition, two species have already been collected at the same locality (e.g., O. cunucunumana with O. rivicola ; and O. cunucunumana with O. viannai sp. nov.), which may lead to misidentifications. The existing records of the genus are from northern South America, southeastern Brazil and Argentina, regions with specialists working with this group of insects. Thus, there is an evident gap in collecting sites in the other South American countries as well as in central-western and northeastern Brazil, where the species of the genus possibly also occur.

Oiovelia is very similar to the Neotropical genus Paravelia Breddin, 1898 , differing from the latter mainly in the form of tarsomere III of all legs, which is expanded, with lateral margins slightly divergent ( Fig. 9 ), whereas in Paravelia the tarsomere III is either cylindrical or subcylindrical, with lateral margins parallel ( Fig. 10 ). In addition, the fore wings of Oiovelia have only a pair of basal maculae starting near the humeral angles, with the rest of the wing at most with pruinosity ( Fig. 26 ). In Paravelia , the fore wings usually have a pair of basal maculae and another apical macula ( Fig. 15 ), with a wide variety of sizes and forms. In some species, however, the apical macula may be absent (e.g., P. basalis (Spinola, 1837) and P. itatiayana Drake 1951 ). On the other hand, Paravelia bullialata Polhemus & Polhemus, 1984 and P. splendoris (Drake & Harris, 1933) ( Fig. 15 ) have the form of the tarsomere III very similar to the species of Oiovelia , which most likely represents convergent character.

Until now, no phylogenetic studies concerning the Neotropical Veliinae have been available from literature, and POLHEMUS (1976) and ANDERSEN (1982) commented that Oiovelia (monotypic at that time) could be just a subgenus or a species group within the genus Paravelia . In this study, we observed that besides the form of the tarsomere III, hitherto the main diagnostic character of the genus, other characters remain constant within the species, such as: absence of black denticles on the body; presence of a pair of oblique punctations on posterior region of head; absence of silver or whitish pubescence on the anterior lobe of pronotum; long dark setae present laterally on the anterior lobe of pronotum; posterior angle of pronotum rounded; fore wings without apical macula; legs without spines, teeth or denticles; two pairs of small tubercles on intersegmental region between the meso- and metasternum; and posterior angle of last connexival segment not developed, rounded. In addition to morphology, Oiovelia species are predominantly inhabitants of foam masses on streams, and so far no species of Paravelia has been correctly recorded from this environment.

Figures

Figs 26–28.Oiovelia cunucunumana Drake & Maldonado-Capriles, 1952, dorsal view:26–27 – macropterous female; 28 – macropterous male. Scale bars = 1 mm.

Figs 22–25. Oiovelia brasiliensis Moreira, Nessimian & Rúdio, 2010.22–24 – dorsal view:22 – apterous male paratype (genital segments removed); 23 – apterous female; 24 – macropterous female; 25 – ventral view of macropterous female (arrow indicates the constriction of abdominal segments III–IV). Scale bars = 1 mm.

Figs 55–58. Oiovelia viannai sp. nov. 55–57 – dorsal view: 55 – apterous male, holotype; 56 – apterous female, paratype; 57 – macropterous female, paratype. 58 – ventral view of macropterous female, paratype. Scale bars = 1 mm.

Figs 32–34. Oiovelia spumicola Spangler, 1986. 32–33 – dorsal view: 32 – apterous male; 33 – apterous female; 34 – ventral view of apterous male (arrow indicates the dark area on sternites V–VI). Abdominal tergites as roman numerals, GS – genital segments. Scale bars = 1 mm.

Figs 78–80. Lateral view of the macropterous female (legs removed). 78 – Oiovelia chenae sp. nov.; 79 – O. hamadae sp. nov.; 80 – O. pydanieli sp. nov. Abbreviations: Roman numerals – abdominal segments, Gon – gonocoxa, Pr – proctiger. Scale bars = 1 mm.

Figs 1–11. 1 – dorsal view of the head of Oiovelia; 2 – dorsal view of the head and pronotum of Oiovelia; 3 – inner view of the protibia showing the grasping comb; 4 – detail of grasping comb; 5 – detail of intersegmental area between the meso- and metasternum showing two pairs of small tubercles; 6 – ventral view of meso- and metasternum of Paravelia; 7 – ventral view of Steinovelia; 8 – ventral view of Platyvelia; 9 – tarsomeres of middle leg of Oiovelia; 10 – tarsomeres of middle leg of Paravelia; 11 – tarsomere III of middle leg of Veloidea (modified from ANDERSEN 1982).Abbreviations: Cox – coxa, Mes – mesosternum, Met – metasternum, Mls – median longitudinal suture, Opt – oblique punctation, Tar – tarsomere.

Figs 29–31. Oiovelia rivicola Spangler, 1986, dorsal view: 29–30 – macropterous male; 31 – macropterous female. Scale bars = 1 mm.

Figs 52–54. Oiovelia pydanieli sp. nov. 52–53 – dorsal view: 52 – macropterous male holotype (arrow indicates the apical pruinose area); 53 – macropterous female. 54 – frontal view of macropterous female (arrows indicate the pruinose areas). Scale bars = 1 mm.

Figs 47–49.Oiovelia chenae sp. nov., dorsal view: 47 – macropterous male holotype; 48 – macropterous male (from São Gabriel da Cachoeira); 49 – macropterous female (from São Gabriel da Cachoeira). Scale bars = 1 mm.

Figs 50–51. Oiovelia hamadae sp. nov., dorsal view: 50 – macropterous male holotype; 51 –macropterous female paratype. Scale bars = 1 mm.

Figs 35–46. Genital segments of male. 35, 38, 41, 44 – dorsal view of genital segment I; 36, 39, 42, 45 – lateral view of genital segment I; 37, 40, 43, 46 – lateral aspect of genital capsule. 35–37 – Oiovelia brasiliensis Moreira, Nessimian & Rúdio, 2010; 38–40 – O. cunucunumana Drake & Maldonado-Capriles, 1952; 41–43 – O. rivicola Spangler, 1986. 44–46 – O. spumicola Spangler, 1986.

Figs 71–77. Lateral view of the left paramere. 71 – Oiovelia brasiliensis Moreira, Nessimian & Rúdio, 2010; 72 – O. cunucunumana Drake & Maldonado-Capriles, 1952; 73 – O. rivicola Spangler, 1986; 74 – O. chenae sp. nov.; 75 – O. hamadae sp. nov.; 76 – O. pydanieli sp. nov.; 77 – O. viannai sp. nov.

Figs 16–21. Streams where part of the Oiovelia specimens examined were collected. 16–19 – Presidente Figueiredo, Amazonas, Brazil: 16 – Cachoeira do Santuário. 17 – Igarapé da Onça. 18 – detail of the typical formation of foam on the black water stream. 19 – detail of Oiovelia specimens on the foam. 20–21 – Luz, Minas Gerais, Brazil: Ribeirão Jorge Grande.

Figs 12–15. 12 – lateral view of Stridulivelia (legs removed) (arrow indicates the transverse sulci); 13 – part of the hind femur of Stridulivelia in dorsal view (arrow indicates the stridulatory devices); 14 – dorsal view of Steinovelia virgata (White, 1879) (arrow indicates the small projections of humeri); 15 – dorsal view of Paravelia splendoris (Drake & Harris, 1933). Scale bars = 1 mm.