Holopothrips acrioris, 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 : 17-18

Holopothrips acrioris sp. n.

( Figs 16–21 )

Diagnostic features. Body (except antenna) uniformly brown; two pairs of long setae on epimeral region; metanotal sculpture formed by slightly elongate and weakly defined reticles, without internal markings; pelta with closely equiangular reticles, without internal markings; sternite II with transversely striate sculpture; males with a single transverse pore plate posterior to discal setae; female spermatheca not enlarged.

Macropterous female: Body ( Fig. 16 ) uniformly brown, fore tibia brownish yellow and all tarsi yellow, tergite X dark brown with extreme base and apex lighter. Antennal segments I–II concolourous with head, II yellow on extreme apex; III–IV yellow, V–VI yellow on basal half and shaded brown on apical half, VII–VIII brown. Fore wings pale to very weakly shaded, without median dark line, clavus shaded; major body setae yellow.

Head ( Fig. 17 ) about 1.2 times as long as width behind eyes, dorsal surface with transverse lines of sculpture, cheeks slightly curved. Eyes well-developed, dorsal length about 0.4 of head length; po with acute to blunt apex, about as long as the dorsal width of the eye. Maxillary stylets parallel, reaching close to posterior margin of eye and less than 0.2 of head width apart. Mouth cone with pointed tip, barely reaching the posterior margin of fore coxae. Antennal segment III with 3 sense cones and IV with 3 sense cones + 1 additional small sense cone.

Pronotum ( Fig. 17 ) trapezoidal, very faint reticulate sculpture medially and weak transverse lines near margins; epimeral sutures incomplete. Six major pairs of pronotal setae, two pairs of epimeral setae; am and aa small with acute to blunt tips, ml, ep and pa well-developed and with blunt tips; basantra faintly indicated; prosternal ferna well-developed, not touching medially. Mesonotum with irregular reticulation medially, which becomes elongated laterally; internal markings on sculpture absent. Metanotum ( Fig. 19 ) with faint irregular reticles medially, elongated laterally, internal markings on sculpture absent; one or two pairs of anterior discal setae and one pair of median major setae present. Fore tarsal hamus not enlarged. Fore wings with 14 to 17 duplicated cilia.

Pelta ( Fig. 18 ) triangular with somewhat irregular margins, anterior margin acute ending in a straight tip, no lateral wings; paired campaniform sensilla present. Sculpture covering the whole pelta; almost equiangular reticles medially, slightly elongated reticles laterally, almost striate on posterior margin, internal markings on sculpture absent. Tergite II ( Fig. 18 ) with well-defined transverse lines, enclosing some small reticles medially; sculpture less defined on further tergites. Tergites II–VII with three pairs of wing retaining setae. Tergite IX setae S1 with blunt to slightly capitate apex, S2 blunt and S3 finely acute. Tube about 0.85 of head length and about 2.3 times as long as greatest width near base, apical width about 0.5 of basal width. Spermatheca ( Fig. 20 ) S-shaped, not thickened or swollen medially.

Measurements (female holotype in microns): Length about 2390; head length 232, width behind eyes 202, po length 52, eye dorsal length 84; median length of pronotum 150, width across ep 315, am 17, aa 20, ml 50, ep 100, pa 65; width of mesonotum 340; fore wing length 900; tergite IX setae S1 170, S2 187, S3 145; tergite X length 217, basal width 97, apical width 45; length(width) of antennal segments III–VIII 75 (35), 65(35), 62(30), 57(27), 55(25), 30(12), respectively.

Macropterous male: Similar to female in both colouration and structure, but slightly smaller. Pore plate ( Fig. 21 ) with punctuate texture present on sternite VIII, a small transverse pore plate posterior to discal setae.

Measurements (male paratype in microns): Length about 2212; head length 235, width behind eyes 185, po length 69, eye dorsal length 82; median length of pronotum 122, width across ep 287, am 12, aa 21, ml 50, ep 92, pa 50; width of mesonotum 302; fore wing length 830; tergite IX setae S1 165, S2 172, S3 130; tergite X length 187, basal width 85, apical width 42; length(width) of antennal segments III–VIII 64 (32), 60(32), 60(30), 50(25), 45(22), 30(12), respectively.

Larvae: body pale with rings of red internal pigmentation on prothorax, metathorax and abdominal segments III–IV and VII; abdominal segments IX–X light brown.

Material studied. Holotype female, Brazil, Rio Grande do Sul, Santana da Boa Vista, in Myrcia selloi gall, 23.ii.2013 (Cavalleri, A.), at UFRGS. Slide code UFRGS 3216 .

Paratypes: 12 males, 24 females and 1 larva collected with holotype, at UFRGS . 1 male, 1 female collected with Holotype, at ANIC .

Non-type specimens: 21 males and 30 females, Brazil, Rio Grande do Sul, Santo Antônio das Missões, in Myrcia selloi gall, 03.ii.2013 (Cavalleri, A.), at UFRGS.

Etymology. Junction of acri (acute) and oris (mouth), indicating the pointed mouth cone.

Comments. This species is very similar to H. conducans , being distinguished only by the lack of elongate reticles with internal markings on the pelta, and having the sculpture on abdominal tergite II almost striate, in contrast to the irregular reticulation in H. conducans . Some other minute variations between both species were observed in coxal setae length, appearance of metanotal sculpture and width of male pore plates. It is also very similar to H. infestans sp. n., but H. acrioris has two pairs of epimeral setae ( Fig. 17 ), third pair of WR on abdominal tergites II–VII, and pelta differently shaped ( Fig. 18 ). Holopothrips acrioris has been collected inducing terminal rosette galls in Myrcia selloi ( Myrtaceae ) ( Fig. 8 ) in Southern Brazil.

Figures

FIGURES 16–21. Holopothrips acrioris sp. nov. holotype and paratypes. (16) body. abd—abdomen, ant—antenna; hd—head; ms—mesothorax; fw—fore wing; mt—metathorax; pel—pelta (first abdominal tergite); pro—prothorax; spe—female spermatheca; tu—tube (tenth abdominal segment); II–X—second to tenth abdominal segments. (17) head and pronotum. aapronotal anteroangular seta; am—pronotal anteromarginal seta; ep—pronotal epimeral setae; mes—mesonotum; metmetanotum (part); ml—pronotal midlateral seta; mx—maxillary stylet; oc—ocellus; pa—pronotal posteroangular seta; popostocular setae. (18) pelta and abdominal tergite II. WR—wing-retaining setae. (19) metanotal sculpture. mds—metanotal discal setae; mms—metanotal major setae; (20) spermatheca (spe). (21) male pore plate on abdominal sternite VIII (mpp).

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).