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

Señorita banana (Musa acuminata AA Group 'Señorita')

Cavendish banana (Musa acuminata) Red banana (Musa acuminata AAA Group 'Red Dacca' Saba banana (Musa acuminata ABB Group 'Saba') Pisang mas or señorita banana ( Musa acuminata AA Group 'Señorita') is a cultivar in Musaceae, a banana with a cylindrical shape and bright yellow skin when ripe, one of the banana cultivars with the shortest fruit and has small seeds or no seeds. M. acuminata (AA Group) 'Señorita' emerged from a completely buried tuber. Stem formed as a pseudostem with heaps of leaf sheaths and succulent, soft, up to 2.5 m high, 42 cm girth at 1 m high. The pseudo stem is green and shiny with a pink-purple base color. The leaf blade is elongated, waxy with a stalk that is sometimes bordered from pink-purple to red, 120 cm long, 45 cm wide and impermeable. The inflorescences hang vertically with red-purple bracts which are yellow or green on the inner surface. Yellow male flowers. The plants start to flower about 231 days after planting....
Read more

Awar awar (Ficus septica)

Awar-awar or lagnob or hauli tree or barabar or sirih popar or tobo tobo ( Ficus septica ) is species of plants in Moraceae, trees grow in bushes or in neglected places and sap contained in roots, twigs, leaves and fruit is used to treat poisoning and digestive problems. F. septica is usually 1-5 m high, although in the forest it can be up to 25 m. Round, hollow and bare branches. Roots, twigs, leaves and fruit will emit a yellow sap and sticky if injured. The base of the leaves is large and spiky, arranged alternately or face to face with a stem length of 2.5-5 cm. Large leaf blade, round egg, 9-30x9-16 cm, rounded base and blunt narrow tip, flat-edged, upper side dark green with 6-12 secondary bones pale white. Fruit paired, single or clustered up to 4 items, short-stemmed, at the base has 3 protective leaves, light green or gray green and 1.5 cm in diameter. F. septica is food for 22 animal species including wasps, bats, birds, monkeys and mice as well as seed dispersing vecto...
Read more

Screw tree (Helicteres isora)

Screw tree ( Helicteres isora ) is a species of plant in the Malvaceae family. It is a shrub or small tree, up to 8 meters tall. It has gray bark and alternate leaves, up to 22 cm long and 17 cm wide, oval in shape, with serrated edges and hairs. The flowers are red or white and reach a total length of 5.5 cm. The fruit is green when unripe, brown or gray when dry, twisted, spiral-shaped, and pointed at the tip. The seeds are black or brown, shiny, and diagonal, triangular, or rectangular. TAXON Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Magnoliopsida Order: Malvales Family: Malvaceae Subfamily: Helicteroideae Tribe: Helictereae Genus: Helicteres Pluk. ex L. in Sp. Pl.: 963 (1753) Species: Helicteres isora L. in Sp. Pl.: 963 (1753) HETEROTYPIC SYNONYMS Helicteres baruensis var. ovata DC. in Prodr. 1: 476 (1824) Helicteres chrysocalyx Miq. ex Mast. in J.D.Hooker, Fl. Brit. India 1: 365 (1874) Helicteres corylifolia Buch.-Ham. ex Dillwyn in Rev. Hortus Malab....
Read more