Sikhotealinia zhiltzovae
| Sikhotealinia zhiltzovae | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Sikhotealinia | ||||||||||||
| Lafer , 1996 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Sikhotealinia zhiltzovae | ||||||||||||
| Lafer , 1996 |
Sikhotealinia zhiltzovae is so far the only described recent type of beetle family of jurodidae . The family belongs to the archostemata group, which is very original compared to the other suborders of the beetles. So far only the holotype is known as the only proven specimen. It was discovered in the Sichote-Alin Mountains in the Primorye region in eastern Russia and initially placed in its own family, Sikhotealiniidae. Kirejtshuk however recognized similarities with the fossil proven way Jurodes ignoramus and placed the species in the family jurodidae today in which it is the only extant is Art. The larvae of the species are unknown.
features
The beetles have a body length of 6.3 millimeters and a width of 2.65 millimeters. Their body is slightly flattened, the surface is covered with a fine, medium-length fluff and is not scaly. The head is wider than it is long and tapers to a neck at the back. The head is also of medium length, but thickly covered with down. The slightly protruding compound eyes are almost round and hairless. Their diameter is about two thirds of the height of the head. The distance between the antennae is three to three and a half times as much as the diameter of the scapus . The antennae are irregularly like a string of pearls (moniliform) and have eleven links, all of which are covered with fine fuzz. The antenna elements enlarge only slightly towards the tip of the antenna. The scapus is about one and a half times longer than the pedicellus ; the third segment is the same length as the scapus , the fourth is the same length as the pedicellus. The fifth to tenth antennae segment is only half as long as the scapus, the last segment is bulbous and slightly longer than the scapus. The front plate ( clypeus ) and the labrum are exposed and approximately rectangular with rounded front corners. The mandibles are strong and have an even cutting surface without teeth. The maxillary palps are four-membered, the last segment is cylindrical. The prementum , a sclerite on the labium, is large and covers the maxillary and labial appendages. The top of the head has two flat, wide elevations behind the feeler points. The end ( frons ) carries three-point eyes ( Ocelli ), a centrally pairs between the compound eyes and two behind it.
The pronotum (fore chest) is almost the same width, like the head but clearly narrower than the wing . There is no extension on the sternum of the prothorax . One can guess the notopleural and sternopleural sutures.
The upper wings carry fine, dense rows of dots along the length. The wing panels are widest in the rear third. The second, membranous pair of wings ( alae ) is well developed. The abdomen has six ventrites (visible abdominal sclerites ). The first ventrit is fully developed and has a central keel, the last has parasagittal notches.
Systematics
Sikhotealinia zhiltzovae largely agrees with the fossil representatives of the Jurodidae from Kazakhstan and China in all verifiable features. It is also biogeographically striking that the recent species still lives in the same area from which all fossil taxa were described. The species differs from the other Archostemata in the veins of the hind wings, which, however, does not, as initially assumed, closely resemble some representatives of the Polyphaga , among other things, the wing has a rudimentary pterostigma . More recent phylogenetic investigations based on morphological characteristics place the Jurodidae family, and thus the species, safely within the Archostemata, possibly as the most primitive still living beetle species with the most plesiomorphic characteristics.
supporting documents
Individual evidence
- ↑ a b c d Rolf G. Beutel, Richard AB Leschen: Handbuch der Zoologie - Coleoptera, Beetles, Volume 1: Morphology and Systematics (Archostemata, Adephaga, Myxophaga, Polyphaga partim) . 1st edition. de Gruyter , 2005, ISBN 3-11-017130-9 (English).
- ^ Rolf G. Beutel, Si-qin Ge, Thomas Hörnschemeyer (2008): On the head morphology of Tetraphalerus, the phylogeny of Archostemata and the basal branching events in Coleoptera. Cladistics 24: 270-298. doi : 10.1111 / j.1096-0031.2007.00186.x
- ↑ Evgeny V. Yan, Bo Wang, Alexander G. Ponomarenko, Haichun Zhang (2014): The most mysterious beetles: Jurassic Jurodidae (Insecta: Coleoptera) from China. Gondwana Research 25: 214-225. doi : 10.1016 / j.gr.2013.04.002
literature
- Rolf G. Beutel, Richard AB Leschen: Handbuch der Zoologie - Coleoptera, Beetles, Volume 1: Morphology and Systematics (Archostemata, Adephaga, Myxophaga, Polyphaga partim) . 1st edition. de Gruyter , 2005, ISBN 3-11-017130-9 (English).