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One generic synonym and one new species of Phlaeothripidae from India (Thysanoptera)
expand article infoKaomud Tyagi, Devkant Singha§, Goutam Kumar Saha§, Vikas Kumar
‡ Centre for DNA Taxonomy, Calcutta, India
§ University of Calcutta, Calcutta, India
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Abstract

Haplothrips shivendraii Tyagi & Kumar, sp. n. is described from Rajasthan state of India. The monobasic Austro-oriental genus Dyothrips Kudô is formally synonymised with Haplothrips.

Keywords

Dyothrips, Haplothrips, India, new species, synonym.

Introduction

The genera Haplothrips, Dyothrips, and Plicothrips belong to tribe Haplothripini in the subfamily Phlaeothripinae, family Phlaeothripidae (Mound and Minaei 2007, Minaei and Mound 2008). Haplothrips was erected by Amyot and Serville (1843) for the single species, Phloeothrips albipennis Burmeister, 1836. It is the second largest genus in the family Phlaeothripidae and comprises the two subgenera Haplothrips and Trybomiella. These are distinguished by the presence or absence of fore wing duplicated cilia, present in Haplothrips and absent in Trybomiella. The genus currently includes 242 extant species, of which 219 are in Haplothrips and 23 in Trybomiella (ThripsWiki 2018). From India, 22 Haplothrips species are recorded, 16 in the subgenus Haplothrips and six in Trybomiella (Tyagi and Kumar 2016).

Dyothrips was first described as a subgenus by Kudô (1974) to include the single species Haplothrips (Trybomiella) cingulatus Pelikan, 1963 from China, and he simultaneously recorded this species from Taiwan (Kudô 1974). However, two further species described from Australia, Zygothrips pallescens Hood, 1919 and Watsoniella helena Girault, 1928 were later synonymized with cingulatus (Pitkin 1973). Bhatti (1995) elevated the status of Dyothrips from subgenus to genus to include the single species Dyothrips pallescens (Hood, 1919). This was based on two morphological characters: incomplete notopleural sutures, and complete mesopresternum. The genus Plicothrips Bhatti, 1979 included two species, Hindsiana apicalis Bagnall, 1915 from India and Hindsiana cameroni Priesner, 1934 from Sudan.

The genus Dyothrips is closely related to Plicothrips by the presence of one sense cone on antennal segment III and incomplete notopleural sutures. However, it can be separated by the presence of two pairs of wing retaining setae in Dyothrips and one pair in Plicothrips. Furthermore, according to the key to Australian genera of the Haplothrips lineage group (Mound and Minaei 2007) Dyothrips is distinguished from Haplothrips based solely on incomplete notopleural sutures. Those authors pointed out that Dyothrips and Haplothrips do not differ in the mesopresternum because this structure is completely sclerotised in the type species of Haplothrips. Recently, we collected a Haplothripini species from Rajasthan state of India and found the notopleural sutures were incomplete in eight specimens, but complete in four specimens, and in a further specimen this suture was incomplete on the left side but complete on the right side. These ten specimens were all collected from the same locality on the same plant, and this variation suggests that the complete or incomplete condition of these sutures is not robust enough to separate the genus Dyothrips from Haplothrips. As a result, the genus Dyothrips is formally synonymized under the subgenus Trybomiella of the genus Haplothrips.

The objective of the present study is to describe a new species of Haplothrips from Rajasthan state of India and to synonymise the genus Dyothrips under the subgenus Trybomiella of genus Haplothrips.

Materials and methods

Holotype and paratypes are deposited in the National Zoological Collections (NZC) at Zoological Survey of India, Kolkata. The specimens were collected by beating vegetation over a white tray, and picked by using a camel-hair brush wet in 70% alcohol and stored in -20 °C. The specimens were then mounted onto the glass slides in Canada balsam for identification. Morphological terminology for adult structures mainly follows Mound and Minaei (2007). Photographs and illustrations were taken with a Leica Trinocular Microscope (Leica DM-1000) using Leica software application suite (LAS EZ 2.1.0). The identification was done using available keys (Pitkin 1976; Ananthakrishnan and Sen 1980; Mound and Minaei 2007; Minaei and Mound 2008).

Taxonomy

Haplothrips Amyot & Serville, 1843

Haplothrips Amyot & Serville, 1843: 640.

Dyothrips Kudô, 1974: 114. Syn. n.

Remarks

The Austro-oriental genus Dyothrips is known by the single species D. pallescens Hood, 1919 from China, Taiwan, Thailand, Japan, Australia, Fiji, and India. Because of variation in the notopleural sutures in the new species described below, Dyothrips can no longer be distinguished from Haplothrips, and they are here formally synonymised. The new combination, Haplothrips pallescens (Hood, 1919), is established here.

Haplothrips shivendraii Tyagi & Kumar, sp. n.

Figures 1, 2, 3, 4, 5, 6, 7, 8, 9

Diagnosis

Both sexes macropterous. Body dark brown, fore wing transparent. Antennae 8-segmented, III with two and IV with four sense cones. Head longer than broad, maxillary stylets widely separated, maxillary bridge complete; with one pair of postocular setae, capitate. Pronotal epimeral setae (ep) well developed, capitate, notopleural sutures incomplete or incomplete. Mesopresternum divided into two lateral triangles. Fore wing without duplicated cilia. Fore tarsal tooth small in female and developed in male. Pelta triangular.

Description

Female macroptera. Body dark brown, all femora, mid and hind tibiae, mid and hind tarsi brown; fore tibiae light brown, fore tarsi yellow with unguitractor dark, fore wing transparent, shaded with brown basally (Figure 1). Antennae brown except light brown segment III. Head longer than broad, dorsal surface with few transverse striae (Figure 3). Maxillary stylets retracted to postocular setae and one third of width apart, maxillary bridge present; one pair of postocular setae well developed, capitate; eyes enlarged dorsally than ventrally; ocelli present. Antennae 8-segmented; segment II with campaniform sensilla situated apically; segment III with two sense cones, IV with four sense cones, V with three-one-one sense cones situated outer and inner margin of apex, and one small sense cone on apex, VI with two, VII with one sense cone; segment VIII not constricted at base (Figure 4). Mouth cone rounded. Pronotum rectangular, 1.7 times as broad as long, and 0.6 times as long as head; dorsal surface with few striae laterally and posteriorly and many small setae; anteroangular setae (aa) small and blunt apically, anteromarginal (am) and midlateral (ml) setae small, pointed or reduced, posteroangular setae (pa) capitate, little longer than aa and shorter than ep, epimeral setae (ep) well developed, capitate, and longer than posteroangular (pa); notopleural sutures incomplete or complete. Mesonotum dorsal surface with faint transversely reticulate sculpture, median and submedian setae little far from posterior margin; lateral setae expanded at apex. Metanotum weakly sculptured with reticulation, with well-developed median pointed setae. Mesopresternum divided into two lateral triangles (Figure 5). Fore wing with median constriction, without duplicated cilia; sub-basal wing setae arranged in one row, well developed and capitate, and S3 the longest (Figure 6). Fore tarsal tooth small (Figure 3). Pelta triangular in shape, surface with reticulation (Figure 7). Tergites III–VII with 2 pairs of wing retaining setae (Figure 8); tergite IX setae S1 bluntly pointed, S2 and S3 finely acute (Figure 9). Sternites II–VIII with accessory setae. Tube shorter than head, anal setae shorter than tube.

Figures 1. 

Haplothrips shivendraii sp. n.: Female

Figures 2. 

Haplothrips shivendraii sp. n.: Male

Figures 3. 

Haplothrips shivendraii sp. n.: Head and Prothorax with fore leg

Figures 4. 

Haplothrips shivendraii sp. n.: Antenna, female

Figures 5. 

Haplothrips shivendraii sp. n.: Prothroax, ventral view, female

Figures 6. 

Haplothrips shivendraii sp. n.: part of fore wing, female

Figures 7. 

Haplothrips shivendraii sp. n.: Pelta, female

Figures 8. 

Haplothrips shivendraii sp. n.: Tergites IV–V, female

Figures 9. 

Haplothrips shivendraii sp. n.: Tergites IX–X, female

Measurements

(holotype female in microns). Body length 2020; head length 225, width across eyes 170, across cheeks 176, across cheeks just before basal collar 159; eye length 98–100, width 50–55; postocular setae lengths 25–28; pronotum median length 133, width 238, lengths of major setae: pa 10, epim 36–42; pelta length 96, width at base 120; antenna length 318, L(W) of antennal segments I 27–29(29), II 39–42 (29), III 43(28), IV 46–49(32), V 41–43(28), VI 40(23), VII 37(20), VIII 27–29(11); fore wing basal setae length S1 39–40, S2 52–54, S3 62–63; tergite IX length 70; setae S1 102–104, setae S2 87–88; tube length 153, width at base 34, at apex 62; anal setae length 99–117.

Male

Macropterous. Colour and structure similar to female (Figure 2). Fore tarsus with distinct and well developed tooth. Male sternite VII without pore areas.

Material studied

Holotype female, INDIA: Rajasthan, Jodhpur, Desert Regional Centre, ZSI, collected from grass, 1.i.2015, (Reg. No.9542/H17), Coll. Shivendra Kumar Singh, in National Zoological Collections (NZC). Paratypes: 8 females 4 males, taken with holotype (Reg. No. 9543/H17 to 9554/H17).

Etymology

This species is credited to Shivendra Kumar Singh for his keen interest and untiring effort for thrips collection dating back to his childhood.

Distribution

India (Rajasthan).

Remarks

This new species is similar to Haplothrips pallescens in having incomplete notopleural sutures in ten specimens. It can be distinguished by the body colour, which is brown in the new species but bicoloured in pallescens; the pronotal anteroangular and anteromarginal setae are not developed in shivendraii, but well developed and capitate in pallescens. There are two sense cones on antennal segment III and four on IV in shivendraii but one sense cone on III and three on IV in pallescens.

According to Indian key to the order Thysanoptera (Ananthakrishnan and Sen 1980), the new species is similar to Haplothrips nigricornis (Bagnall) by the length of the pronotal midlateral setae and anteroangular setae. It can be distinguished by the yellow fore tarsus (yellowish brown in nigricornis), light brown fore tibia (fore tibia brown with slightly paler apex), presence of four sense cones on segment IV (4+1 in nigricornis); pronotum with posteroangular setae developed (reduced in nigricornis); and maxillary stylets are more widely separated in shivendraii than nigricornis.

Acknowledgements

KT, VK, and DS are grateful to the Director, Zoological Survey of India, for his encouragement and moral support, and for providing necessary facilities. We are thankful to Dr L A Mound (CSIRO, Australia) for helping KT with identification of this species. The study is financially supported by AICOPTAX project “Taxonomic Studies of Tubulifera (Thysanoptera) from India” to VK and core funding of Zoological Survey of India, Kolkata through its research programme to the corresponding author. The present study forms part of the thesis work of the second author.

References

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  • Bhatti JS (1979) Studies in some haplothripine forms. Nouvelle Revue Entomologique 9: 305–311.
  • Bhatti JS (1995) Studies on some Phlaeothripidae (Insecta: Tubulifera). Zoology (Journal of Pure and Applied Zoology) 5: 97–110.
  • Pitkin BR (1976) A revision of the Indian species of Haplothrips and related genera (Thysanoptera: Phlaeothripidae). Bulletin of the British Museum (Natural History), Entomology 34: 221–280.
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  • ThripsWiki (2018) Thrips Wiki – providing information on the World’s thrips. http://thrips.info/wiki [accessed 1 June 2018]
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