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

Sojiwan Temple

Sojiwan Temple or Candi Sojiwan or Candi Sajiwan is a Buddhist monument in the Kewu Plain , village of Kebon Dalem Kidul, Prambanan District, Klaten Regency, Central Java Province, Indonesia. This temple has a characteristic that is 20 reliefs at the foot of the temple associated with the stories of Pancatantra or Jataka. Sojiwan temple was completely restored in 2011. Some inscriptions say that was built between 842 and 850 AD. The Rukam inscription in 829 Saka (907 AD) mentions the ceremony of the inauguration of the improvement of Rukam Village by Nini Haji Rakryan Sanjiwana which was destroyed by a volcanic eruption. The residents of Rukam Village were given the obligation to maintain a sacred building located in Limwung. The sacred building was later attributed to the Sojiwan Temple, while Nini Haji Rakryan Sanjiwana was associated as Queen Pramodhawardhani. Sojiwan Temple was first reported in 1813 by Colonel Colin Mackenzie, a messenger of Raffles, who was collecting arch...
Read more

Chameleon forest dragon (Gonocephalus chamaeleontinus)

Bunglon hutan or chameleon anglehead lizard or chameleon forest dragon ( Gonocephalus chamaeleontinus ) is an animal species in Agamidae, having a larger size than other species, the most unique head shape and has the ability to change color by changing mood rather than for camouflage. Morphology G. chamaeleontinus has a total length of 40 cm, the muzzle to the buttocks is 16 cm, the base color is green with orange, yellow to brownish spots and sexual dimorphism. The eyes are protected by a movable eyelid surrounded by a slightly darker color, while males have a bright blue color around the eyes. Short head with a triangle and thorns above the eyes. Medium-sized head scales, vary, smooth and have a little tubercle that extends above the ear. Heterodont teeth with acrodont type and dorsal tongue are covered by reticular papillae. The upper labial scale consists of 10-12 units and the lower labial scale consists of 11-14 units. Dorsal body scales are composed of small and fine ...
Read more