Body uniformly brown; including legs and antennal segments; head somewhat darker; fore wing strongly shaded. Head with one pair of long ocellar setae, also one pair of postocular setae well developed. Antennae long and 8-segmented, III & IV each with transverse sensorium at apex. Pronotum widest at posterior, usually with two pairs of long posteroangular setae. Meso & metathoracic spinula present. Mesonotum with a long setae arising laterally; metanotum with weak sculpture medially; paired campaniform sensilla present; median pair of setae arising close to posterior margin. Fore wing with both rows of setae complete. Tarsi 2-segmented. Abdominal tergites without microtrichia and X with a pair of stout trichobothria. Sternites III–VII with 2 to 4 pairs of discal setae; ovipositor weakly developed. Female macroptera.
Male with a dorsal glandular area on head.
Intraspecific variation
Wingless specimens collected deposited at USNM were considered belonging to this species by D.J. Hood. However, this form shows only one pair of long posteroangular setae on pronotum, minute mesonotal lateral setae and lacks trichobothria on abdominal tergite X (Mound & O’Neill, 1974). Moreover, the sensoria on antennal segments III & IV are minute.
Genus and similar species information
Merothrips includes 13 extant species, many of them described from the Neotropics. They all have antennae 8-segmented and the transverse sensoria on segments III & IV are and sometimes slightly inflated. Many species are known only from apterous forms. Merothrips mirus is unique in having two pairs of pronotal posteroangular setae. The identity of several apterous females identified by D.J. Hood as this species remains doubtful. A key to Merothrips species is given by Mound & O’Neill (1974).
Lives on leaf litter and on dead branches, and possibly feeds on fungal hyphae.
Economic importance
Not recorded.
References suggested
Mound LA & O'Neill K (1974) Taxonomy of the Merothripidae, with ecological and phylogenetic considerations (Thysanoptera). Journal of Natural History, 8: 481–509.
Mound LA & Marullo R. (1996). The Thrips of Central and South America: An Introduction. Memoirs on Entomology, International, 6: 1–488.
Published in: 23/12/2016 Posted by: Mariana Lindner
