One generic synonym and one new species of Phlaeothripidae from India (Thysanoptera)

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


Introduction
The genera Haplothrips, Dyothrips, and Plicothrips belong to tribe Haplothripini in the subfamily Phlaeothripinae, family Phlaeothripidae Minaei 2007, Minaei andMound 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).
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 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  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.
Male. Macropterous. Colour and structure similar to female (Figure 2). Fore tarsus with distinct and well developed tooth. Male sternite VII without pore areas.
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.