Mecoptera: Meropeidae: Merope tuber Newman, 1838
Merope tuber is the only representative of the family Meropeidae in North America. The Australian earwigfly, Austromerope poultoni Killington and the extinct species Boreomerope antiqua Novokschonov, known from the Middle Jurassic in Siberia, are the only other known species in the family (1). The first specimen of Merope tuber was collected in 1837 by Edward Doubleday in Trenton Falls, New York. In 1838, a contemporary of Charles Darwin, Edward Newman, described the species. The holotype is currently held in the Natural History Museum in London (1).
«Meropia» is a Latin modification of the Greek combination «meros» and «opia» essentially meaning «part» of the «eye». Somma and Dunford (2007) have concluded that Newman named the genus Merope after the dullest of the Pleiades sisters. Its common name, the «earwigfly» is derived from the male genital claspers which resemble the pinching cerci of dermapterans (earwigs). It’s currently unknown how these claspers are involved in the mating process. Females look very similar to males but lack the forceps-like claspers.
Merope tuber is native to the eastern deciduous forests in North America and occurs from southeastern Canada (Ontario) south to Florida, west to Iowa and Kansas (1, 3). The Florida Natural Areas Inventory lists the species as very rare and vulnerable to extinction. Very little is known of its life history and the larvae have not yet been recognized. The larvae of the earwigfly could provide important information about the evolutionary relationships in holometabolous insects (4). The undergraduate Entomology club at Cornell has established the species as their mascot and have made it their goal to find and describe the larval stage! The disjunct ranges of Merope tuber and Austromerope poultoni might have once overlapped in South America and Antarctica but this tie was likely severed over 60 million years ago (5).
The jugum, located posteriorly at the base of the fore wing, is serrated and rubs against the serrated thorax producing sound. The stridulating sounds may be used for defense or to communicate with the opposite sex in mating. Earwigflies are weak fliers, and their flattened bodies may suggest that they live under rocks and in cracks and crevices (4). Adults are active at night (1).
The NCSU Insect Museum has 10 specimens of Merope tuber from North Carolina: 2 specimens from Orange County in 1999, 1 from Henderson Co. and 1 from Duplin Co. in 1984, 1 from Wake Co. in 1987, 1 from Macon Co. in 2007, 1 from Avery Co. in 1936, and 2 specimens from Swain Co. in 1998 and 2001. There are also 2 specimens with label data from «Davenport, WVa» (likely Davenport, Virginia) collected in 1920. Our records extend the range of the species into the Piedmont of North Carolina (the middle 35% of the state)! Since collecting techniques have been greatly improved in the recent past (though Merope is often collected simply by turning over rocks!) the apparent range of the species has been expanded quite a bit.
Collection methods and preservation:
The specimens in the NCSU Insect Museum were collected either in Malaise traps, yellow pan traps, or at light traps. The specimens should be preserved in 95% ethanol or pointed. Spring and summer are around the corner, so start flipping logs and searching through leaf litter around streams for the larvae!!