Temporal range: Middle Jurassic–Recent
|Mordella aculeata ; note the "pintail"|
|Family:|| Mordellidae |
The Mordellidae are a family of beetles commonly known as tumbling flower beetles for the typical irregular movements they make when escaping predators, or as pintail beetles due to their abdominal tip which aids them in performing these tumbling movements. Worldwide, there are about 1500 species.
The apparently tumbling movements are composed of a series of very rapid separate jumps (each jump of a duration of approximately 80 ms). They result from the beetle's efforts to get itself back into take-off position for flight when it has been in either lateral or dorsal position. Each individual jump should be considered as an extended rotation, performed by one leg of the third leg pair (metapodium). Depending on whether the left or the right metapodium is used as the leg that provides the leverage for take-off, change occurs in the direction of the jump. The energy for propulsion varies with the beetle's immediate muscle work, so that jump lengths and heights vary, with rotation frequencies recorded up to 48 per second (Mordellochroa abdominalis) around the gravitation centre of the body's longitudinal axis. Additional revolving around the transverse axis (at lower frequency) effects spiralling somersaults that are perceived as tumbling. The pintail (pygidium) is of no significance for the jump. While the pintail is no significance for the jump, meta-trochanter-femur (thighs and surrounding rings of the third leg pair)has a great capacity of free rotation (up to 270 degrees, at one level only). This capacity is due to a screw joint that connects the base of metacoxa to the head of trochanter. The nut gradient is 21 degrees (as seen under a scanning electron microscopy SEM, 1985). Technically similar jumps, though less powerful, can be observed in family Melandryidae (=Serropalpidae) (genus Orchesia) and family Scraptiidae (genus Anaspis). Their coxa-trochanter-joints are of similar structure. It can be assumed that the capacity of a tumbling form of locomotion is rooted in a common phylogeny and can therefore not be ascribed specifically to Mordellidae.Meanwhile, other authors have also pointed out the speciality of the real screw joint in nature. (2011) The weevil of the genus Trigonopterus , Curculionidae in the Asian tropical rainforest, for example, has an even tighter connective construction in the Coxa -Trochanter joint than is found in Mordellidae. This construction, however, does not facilitate an equally high angular velocity of the torque. The joint here serves to provide a better grip on plants and easier climbing.
This family has two living subfamilies – Mordellinae and Ctenidiinae – and a prehistoric one known only from fossils (Praemordellinae). Another fossil genus, Liaoximordella , was previously treated as distinct monotypic family Liaoximordellidae, but is now regarded as very primitive and probably basal member of the Mordellidae.
FAMILY Mordellidae Latreille, 1802
The bean weevils or seed beetles are a subfamily (Bruchinae) of beetles, now placed in the family Chrysomelidae, though they have historically been treated as a separate family. They are granivores, and typically infest various kinds of seeds or beans, living most of their lives inside a single seed. The family includes about 4,350 species and are found worldwide.
The Dytiscidae – based on the Greek dytikos (δυτικός), "able to dive" – are the predaceous diving beetles, a family of water beetles. They occur in virtually any freshwater habitat around the world, but a few species live among leaf litter. The adults of most are between 1 and 2.5 cm (0.4–1.0 in) long, though much variation is seen between species. The European Dytiscus latissimus and Brazilian Megadytes ducalis are the largest, reaching up to 4.5 cm (1.8 in) and 4.75 cm (1.9 in) respectively. In contrast, the smallest is likely the Australian Limbodessus atypicali of subterranean waters, which only is about 0.9 mm (0.035 in) long. Most are dark brown, blackish, or dark olive in color with golden highlights in some subfamilies. The larvae are commonly known as water tigers due to their voracious appetite. They have short, but sharp mandibles and immediately upon biting, they deliver digestive enzymes into prey to suck their liquefied remains. The family includes more than 4,000 described species in numerous genera.
Mordella is the type genus of the tumbling flower beetle family (Mordellidae), its subfamily Mordellinae and the tribe Mordellini. It is widely distributed in the Holarctic and adjacent regions. The larvae are primarily dead wood borers.
Glipa is a genus of beetles in the family Mordellidae, containing the following species:
Glipidiomorpha is a genus of beetles in the family Mordellidae, containing the following species:
Hoshihananomia is a genus of tumbling flower beetles in the family Mordellidae. There are at least 40 described species in Hoshihananomia.
Mordellaria is a genus of tumbling flower beetles in the family Mordellidae. There are more than 10 described species in Mordellaria.
Ermischiella is a genus of beetles in the family Mordellidae, containing the following species:
Falsomordellistena is a genus of tumbling flower beetles in the family Mordellidae, containing the following species:
Glipostena is a genus of beetles in the family Mordellidae, containing the following species:
Glipostenoda is a genus of beetles in the family Mordellidae, containing the following species:
Mordellina is a genus of tumbling flower beetles in the family Mordellidae.
Mordellistena is a genus of beetles in the family Mordellidae, containing the following species:
Neomordellistena is a genus of beetles in the family Mordellidae, containing the following species:
Stenalia is a genus of beetles in the family Mordellidae, containing the following species:
Mordellinae is a subfamily of beetles commonly known as tumbling flower beetles for the typical irregular movements they make when escaping predators, or as pintail beetles due to their abdominal tip which aids them in performing these tumbling movements.
The Stenaliini are a tribe of beetles in the family Mordellidae.
The Conaliini are a tribe of beetles in the family Mordellidae.
Neomordellistena is a subgenus of the beetlegenus Neomordellistena in the family Mordellidae, containing the following species:
Saperdini is a tribe of longhorn beetles of the subfamily Lamiinae.
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