Skip to main content

Henrik Madsen's earwig (Apachyus madseni), 55 million year old fossil from Ypresian Fur Formation in Denmark

Dlium Henrik Madsen's earwig (Apachyus madseni), 55 million year old fossil from Ypresian Fur Formation in Denmark

NEWS - Henrik Madsen's earwig (Apachyus madseni Simonsen & Rasmussen sp. nov.) is reported based on a nearly complete 55 million year old fossil from the Ypresian Fur Formation in northwestern Denmark. The new fossil is not only a new addition to the mo-clay fauna, but also an extension of its historical biogeographic range.

The last few decades have seen an increasing focus on the richness of the insect fossil record found in the Ypresian Fur Formation in northwestern Denmark. One insect order that has to some extent been spared from this surge in taxonomic knowledge from the site is the Dermaptera commonly known as earwigs.

Now, Thomas Simonsen from the Natural History Museum Aarhus and Jan Rasmussen from the Mors Museum and colleagues report a new species of Dermaptera in Apachyus Serville as the first fossil record in the Apachyidae which currently consists of two species-poor genera and is distributed across the Indian Subcontinent, Southeast Asia, Australia and Central Africa.

A. madseni has a total length (excluding cerci): 18.8 mm. Head subtriangular, prognathous with clearly preserved mandibles; antennae not preserved; eyes discernible; anterior cervical sclerite well preserved and small; posterior cervical sclerite poorly preserved but appearing larger than the anterior cervical sclerite. Pronotum well preserved, sub-circular with longitudinal groove, femur and tibia of foreleg poorly preserved.

Mesothorax preserved with femur and tibia of both midlegs poorly preserved, tegmen poorly preserved but discernible, subrectangular. Metathorax with femur of right hindleg poorly preserved. Hind wings preserved with squama clearly visible.

Abdomen well preserved with most segments discernible; segment 10 well preserved and broad, with broad, subrectangular and smooth terminal squamopygidium obscuring the pygidium; cerci well preserved, simple, arcuate/broad sickle-shaped, widely separated at base, strongly curved around the tip of the abdomen.

The eponymous name honors Henrik Madsen who has been collecting fossils in the Fur Formation of Denmark for more than three decades. A. madseni can be distinguished from all other Apachyus by its broad and short squamopygidium with a smooth and slightly convex distal margin.

A. madseni is the second species of Dermaptera described from the Fur Formation and the first fossil representative of Apachyidae to be described globally. The family currently consists of 15 current species in two genera (13 in Apachyus and 2 in Dendroiketes) and A. madseni.

The current species are distributed in Central Africa (3 species) and the remainder from India to the Philippines and Australia. The discovery of A. madseni represents an expansion of the range of Apachyidae, indicating that the distribution of a family does not necessarily reflect its past distribution or biogeographic origin.

Original research

Thomas J. Simonsen, René L. Sylvestersen, Kent Olsen & Jan A. Rasmussen (2024). Apachyus madseni (Dermaptera: Apachyidae) sp. nov. from the Ypresian Fur Formation of Denmark: the first fossil record of the enigmatic earwig family Apachyidae. Palaeoentomology 007 (5): 638–644, DOI:10.11646/palaeoentomology.7.5.7

Dlium theDlium
Labels:

Popular Posts

Humpback whales (Megaptera novaeangliae) manufacture bubble-nets as tools to increase prey intake

NEWS - Humpback whales ( Megaptera novaeangliae ) create bubble net tools while foraging, consisting of internal tangential rings, and actively control the number of rings, their size, depth and horizontal spacing between the surrounding bubbles. These structural elements of the net increase prey intake sevenfold. Researchers have known that humpback whales create “bubble nets” for hunting, but the new report shows that the animals also manipulate them in a variety of ways to maximize catches. The behavior places humpbacks among the rare animals that make and use their own tools. “Many animals use tools to help them find food, but very few actually make or modify these tools themselves,” said Lars Bejder, director of the Marine Mammal Research Program (MMRP), University of Hawaii at Manoa. “Humpback whales in southeast Alaska create elaborate bubble nets to catch krill. They skillfully blow bubbles in patterns that form a web with internal rings. They actively control details such ...
Read more

Temulawak (Curcuma zanthorrhiza)

Temulawak or Java ginger or Javanese ginger or Javanese turmeric or Curcuma xanthorrhiza ( Curcuma zanthorrhiza ) is a plant species in Zingiberaceae, grows well in loose soil in tropical forests in the lowlands to an altitude of 1500 meters above sea level and tubers are used for medicinal herbs and drinks. C. zanthorrhiza has pseudo stems up to 2 m tall. The stem is a midrib of upright, overlapping leaves, green or dark brown in color. Rhizomes are perfectly formed, large, branched and reddish brown, dark yellow or dark green. Each bud forms 2-9 leaves with a circular shape extending to lancet, green or light purple to dark brown, leaves 31-84 cm long and 10-18 cm wide, stems 43-80 cm long and each strand is connected with a midrib. Flowers are dark yellow, uniquely shaped and clustered with lateral inflorescences. The stems and scales are in the form of lines, 9-23cm long and 4-6cm wide, having protectors with comparable crowns. Petals are white, hairy and 8-13mm long. The...
Read more

Bright white flat-backed millipede (Trichopeltis jiyue) like moon emerging from behind dark rain clouds

NEWS - Bright white flat-backed millipede ( Trichopeltis jiyue sp. nov.) from Ailaoshan National Nature Reserve in Yunnan Province, is the second recorded epigean species of Trichopeltis Pocock 1894 in China. Jiyue (Chinese spelling) refers to the bright white appearance of the animal, like the moon emerging from behind dark rain clouds. Polydesmida is one of the most diverse orders of Diplopoda (millipedes) with about 5000 species in 30 families and is widely distributed worldwide. All Polydesmida are blind, eyeless and metaterga usually show small to prominent lateral paranota or paraterga. Cryptodesmidae Karsch 1880 is a family Polydesmida with about 40 genera and 130 species distributed in the Neotropics (Mexico to Argentina), Afrotropics (continental sub-Saharan Africa) and Asia-Australasia (Central Asia and the Himalayas to Japan and Papua New Guinea). In tropical or subtropical Asia and Australasia, 12 genera and 36 species have been documented in Cryptodesmidae. Trichopeltis P...
Read more