Holopothrips curiosus, Lindner & Ferrari & Mound & Cavalleri, 2018

Lindner, Mariana F., Ferrari, Augusto, Mound, Laurence A. & Cavalleri, Adriano, 2018, Holopothrips diversity-a Neotropical genus of gall-inducing insects (Thysanoptera, Phlaeothripidae), Zootaxa 4494 (1), pp. 1-99 : 32-35

Holopothrips curiosus sp. n.

( Figs 69–74 )

Diagnostic features. Body (except antenna) uniformly brown, including fore tibiae; maxillary stylets V-shaped; one pair of long pronotal setae on epimeral region; metanotal sculpture with elongate reticles looking almost striate, with internal markings; reticulation on pelta without internal markings; male with three pore plates on sternites VII–VIII, posterior plate on VII interrupted medially; female spermatheca not enlarged.

Macropterous female: Body ( Fig. 69 ) uniformly brown, with fore tarsi lighter, tergite X darker basally and concolourous with body on apex. Antennal segments I–II concolourous with head, II lighter on extreme apex, III yellow shaded brown on apical third, IV–VI yellow basally and brown apically, VII–VIII brown. Fore wings pale but weakly shaded near base, without median dark line, clavus shaded; major body setae light brown.

Head ( Fig. 70 ) about 1.5 times as long as width behind eyes, dorsal surface with transverse lines of sculpture, cheeks slightly curved. Eyes well-developed, dorsal length about 0.39 of head length; po with blunt to slightly expanded apex, almost as long as the dorsal width of the eye. Maxillary stylets V-shaped, reaching halfway to po level and about half of head width apart. Mouth cone with rounded tip, not reaching ferna. Antennal segment III with 3 sense cones and IV with 3 sense cones + 1 additional small sense cone.

Pronotum ( Fig. 70 ) rectangular to weakly trapezoidal, surface smooth medially, with few transverse lines of sculpture near posterior margin; epimeral sutures incomplete and short. Five major pairs of pronotal setae, one pair on epimeral region; all pairs well-developed, am with blunt tip, aa, ml, ep and pa with capitate tips. Basantra absent; prosternal ferna well-developed, not touching medially. Mesonotum ( Fig. 74 ) with irregular reticulation medially, which becomes elongated near margins, in some specimens looks closer to transverse lines; internal markings on sculpture absent. Metanotum ( Fig. 74 ) with longitudinal lines, sometimes forming a striate pattern, sometimes enclosing thin and elongated reticles, internal markings on sculpture present; one pair of anterior discal setae and one pair of median major setae present. Fore tarsal hamus not enlarged. Fore wings with 7 to 12 duplicated cilia.

Pelta ( Fig. 71 ) triangular with very irregular margins, anterior margin acute, no lateral wings but with weak projections near base; paired campaniform sensilla present. Sculpture covering the whole pelta; irregular elongated reticles medially, larger laterally, short transverse lines near posterior margin, internal markings on sculpture absent. Tergite II with transverse lines of sculpture enclosing elongated reticles; sculpture less defined on further tergites. Tergites III–VII with three pairs of wing retaining setae, sometimes absent on IV–V. Tergite IX setae S1, S2 and S3 with finely acute apexes. Tube about 0.7 of head length and about 2.2 times as long as greatest width near base, apical width about 0.5 of basal width. Spermatheca S-shaped, not thickened or swollen medially ( Fig. 72 ).

Measurements (female holotype in microns): Length about 1916; head length 225, width behind eyes 169, eye dorsal length 86; median length of pronotum 105, width across ep 207, am 15, aa 7, ml 25, ep 55, pa 49; width of mesonotum 225; fore wing length 730; tergite IX setae S1 182, S2 177, S3 170; tergite X length 150, basal width 72, apical width 37; length(width) of antennal segments III–VIII 65 (25), 54(27), 57(27), 52(25), 52(22), 30(10), respectively.

Macropterous male: Similar to female in both colouration, size and structure. Pore plates ( Fig. 73 ) with reticulate texture and present on sternites VII–VIII, two anteroangular plates and one transverse band posterior to discal setae, this band interrupted medially on VII.

Measurements (male paratype in microns): Length about 2014; head length 252, width behind eyes 172, po length 60, eye dorsal length 97; median length of pronotum 119, width across ep 210, am 22, aa 12, ml 30, ep 70, pa 59; width of mesonotum 240; fore wing length 790; tergite IX setae S1 165, S2 175, S3 172; tergite X length 167, basal width 75, apical width 40; length(width) of antennal segments III–VIII 67 (25), 51(29), 57(27), 55(24), 55(20), 35(10), respectively.

Larvae: Body mainly yellow but with rings of red internal pigmentation on thorax and abdomen.

Material studied. Holotype female, Brazil, Rio Grande do Sul, São Francisco de Paula, in Siphoneugena reitzii gall, 1.xii.2012 (Cavalleri, A.), at UFRGS. Slide code UFRGS 3436 .

Paratypes: 2 males, 1 female and 4 larvae collected with holotype, at UFRGS.

Etymology. Named after the species having a curious combination of several uncommon traits within the genus.

Comments. Holopothrips curiosus is a relatively small species with head longer than wide. It is uncommon in having the body fully brown, including fore tibia and all tarsi ( Fig. 69 ), which tend to be yellow in most Holopothrips species. The sculpture on abdominal tergite II apparently bears few and weakly defined striae inside some reticles. The galls induced by this thrips appear as rolled or folded leaf margins, with necrotic spots along the surface ( Fig. 1 ).

Figures

FIGURES 69–74. Holopothrips curiosus sp. nov. holotype and male paratype. (69) body; (70) head and pronotum; (71) pelta; (72) spermatheca; (73) pore plates on abdominal sternites VII–VIII; (74) mesonotum and metanotum.

FIGURES 1–9. Leaf-galls induced by Holopothrips (white arrows). (1) galls on Siphoneugena reitzii (by H. curiosus); (2) galls on Myrciaria floribunda (by H. spermathecus) (Photo: André Santana); (3) gall on Myrcia guianensis (by H. molzi); (4) gall on Myrcia retorta (by H. striatus); (5) gall on Myrcia sp. (by H. cardosoi) (Photo: João C. Cardoso); (6) gall on Myrcia splendens (by H. conducans); (7) gall on Myrcia splendens (by H. longisetus); (8) gall on Myrcia selloi (by H. acrioris); (9) galls on Neomitranthes obscura (by H. varicolor) (Photo: Sheila Carvalho-Fernandes).