Female macropterous; body color mostly dark brown, with trochanters, legs’ knees and tarsi lighter; antennae almost black, with base of segments III–V and apex of VI yellowish, VII and base of VIII almost white; wings light brown, with darker base, and median vein almost black. Antennae 8-segmented, antennomere III with 2 and IV with 4 sense cones; antennomeres I–V with multiple thick and elongated setae, with rounded to expanded apexes. Head longer than wide, with a projection in front of eyes and lateral margins nearly parallel; with three pairs of long setae dorsally and multiple short but stout setae dorso-laterally; maxillary stylets about 1/4 to 1/3 of head width apart, extending for less than half of head length. Pronotum reticulated, with 5 pairs of short but well-developed setae, the epimeral pair longest; prosternal basantra absent. Metanotum irregularly reticulated, one pair of well-developed median setae and a smaller pair on anterior angles. Metathoracic sternopleural sutures absent. Pelta triangular and wide, reticulated, with two pairs of thick and long setae on posterior angles; abdomen reticulated, tergites II–VII with 2 pairs of wing-retaining setae and two pairs of posteromarginal setae arising from large tubercles. Tube cylinder-shaped, about 12x as long as basal width, with lateral setae. All legs similar in appearance, femora with setae arising from tubercles, fore tarsi without a tooth. Fore wings without duplicated cilia.
Male macropterous. Similar to female, with a tarsal tooth on fore legs. Pore plates absent.
Intraspecific variation
Unknown.
Genus and similar species information
The only species in Saurothrips has several similarities to members of Actinothrips, Zactinothrips and Zeugmatothrips, such as the lack of basantra or metathoracic sternopleural sutures, and the elongated tube with lateral setae. Saurothrips assai is distinguished from the first two genera for lacking duplicated cilia on forewings, and abdominal segment VIII is not constricted medially; and from Zeugmatothrips by the long post-ocellar setae and males with a well-developed fore tarsal tooth. Another distinctive trait of Saurothrips assai is the presence of two pairs of wing-retaining setae on abdominal tergites, whereas the most common state in Idolothripinae is a single pair of such setae.
