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Monday, 7 March 2016

DEATHWATCH BEETLE

The deathwatch beetle, Xestobium rufovillosum, is a woodboring beetle. The adult beetle is 7 millimetres (0.28 in) long, while the xylophagous  larvae are up to 11 mm (0.43 in) long.
To attract mates, these woodborers create a tapping or ticking sound that can be heard in the rafters of old buildings on quiet summer nights. They are therefore associated with quiet, sleepless nights and are named for the vigil (watch) kept beside the dying or dead, and by extension the superstitious have seen the death watch as an omen of impending death.
Xestobium.rufovillosum.jpg
Scientific classification
Kingdom:Animalia
Phylum:Arthropoda
Class:Insecta
Order:Coleoptera
Family:Anobiidae
Genus:Xestobium
Species:X. rufovillosum
The term "death watch" has been applied to a variety of other ticking insects, including Anobium striatum, some of the so-called booklice of the family Psocidae, and the appropriately named Atropos divinatoria and Clothilla pulsatoria.
The larva is very soft, yet can bore its way through wood, which it is able to digest using a number of enzymes in its alimentary canal, provided that the wood has experienced prior fungal decay. 
In Culture
Its nature as an ill omen is alluded to in the fourth book of John Keats', "Endymion", : "...within ye hear / No sound so loud as when on curtain'd bier / The death-watch tick is stifled." ("Stifled" because the death it was portending has taken place.)
The deathwatch beetle is mentioned in the film Practical Magic, and its characteristic ticking sound serves as the harbinger of death.
The beetle is also mentioned in the History Channel series Life After People (season one, episode six), wherein it is shown "eating" the Mona Lisa.
Ray Bradbury mentioned them in his work Something Wicked This Way Comes,wherein the antagonist carnival's speciality is claimed to be "to examine, oil, and repair Death-Watch Beetles."
German progressive rock band Hoelderlin has a 17-and-a-half-minute-long track, titled "Deathwatchbeetle", on their eponymous album from 1975.
"Tick-tock go the deathwatch beetles" is the opening line of the 1982 song The Jet Set Junta by English new wave band The Monochrome Set.
In 1838 Henry David Thoreau published an essay mentioning the deathwatch beetle. It is possible that this essay influenced Edgar Allan Poe's 1843 short story "The Tell-Tale Heart" and that the sound the protagonist was hearing at the end of that story was that of a beetle tapping inside the wall, not the beating of the (dead) victim's heart.
They were mentioned in the BBC series Sherlock, in which Sherlock is giving a toast at Watson's wedding and makes a comparison of John and Mary’s wedding to “the death-watch beetle that is the doom of our society and, in time, one feels certain, our entire species.”
In Rogue Male based on a Geoffrey Household novel, Major Quive-Smith (John Standin) is staying at Drake's countryside boardinghouse while manhunting Sir Robert (Peter O'Toole). One night Sir Robert tries to steal food from Drake's dairy and falls through the rafters. Quive-Smith and Drake come out to investigate the commotion, and Quive-Smith says the cause of the cave-in was a deathwatch beetle and that he had seen the prior results of the beetle's work while staying in East Riding.
References

  1. ^ E. A. Parkin (1940). "The digestive enzymes of some wood-boring beetle larvae". (PDF). Journal of Experimental Biology 17 (4): 364–377.
  2. ^ http://www.bartleby.com/126/35.html.
  3. ^ http://www.eapoe.org/pstudies/ps1970/p1971105.html.
External Links


- Wikipedia 

ANOBIIDAE

Anobiidae is a family of beetles. The larvae of a number of species tend to bore into wood, earning them the name "woodworm" or "wood borer". A few species are pests, causing damage to wooden furniture and house structures, notably the deathwatch beetle, Xestobium rufovillosum, and the common furniture beetle, Anobium punctatum.

Hedobia imperialis III.jpg
fan-bearing wood-borer, Hedobia imperialis
Scientific classification
Kingdom:Animalia
Phylum:Arthropoda
Class:Insecta
Order:Coleoptera
Infraorder:Bostrichiformia
Superfamily:Bostrichoidea
Family:Anobiidae
Fleming, 1821
It includes the subgroups:
  • Anobiinae Kirby, 1837
    • Anobium Fabricius, 1775 (furniture beetles)
    • Gastrallus Jacquelin du Val, 1860
    • Hadrobregmus Thomson, 1859
    • Microbregma Seidlitz, 1889
    • Oligomerus Redtenbacher, 1849
    • Priobium Motschulsky, 1845
    • Stegobium Motschulsky, 1860 (drugstore beetle)
  • Dorcatominae Thomson, 1859
    • Anitys Thomson, 1863
    • Caenocara Thomson, 1859
    • Dorcatoma Herbst, 1792
    • Stagetus Wollaston, 1861
  • Dryophilinae LeConte, 1861
    • Dryophilus Chevrolat, 1832
    • Grynobius Thomson, 1859
  • Ernobiinae Pic, 1912
    • Episernus Thomson, 1863
    • Ernobius Thomson, 1859
    • Ochina Sturm, 1826 (ivy-boring beetles)
    • Xestobium Motschulsky, 1845 (deathwatch beetles)
  • Eucradinae Le Conte, 1861
    • Hedobia Dejean, 1821
  • Ptilininae Shuckard, 1840
    • Pseudoptilinus Leiler, 1963
    • Ptilinus Müller, 1764
  • Ptininae Latreille, 1802 (spider beetles)
    • Eupauloecus Mulsant & Rey, 1868
    • Gibbium Scopoli, 1777
    • Mezium Curtis, 1828
    • Niptus Boieldieu, 1856
    • Pseudeurostus Heyden, 1906
    • Ptinus Linnaeus, 1767
    • Sphaericus Wollaston, 1854
    • Trigonogenius Solier, 1849
  • Xyletininae Gistel, 1856
    • Lasioderma Stephens, 1835 (cigarette beetles)
    • Xyletinus Latreille, 1809

- Wikipedia 

PROTHORAX

The prothorax is the foremost of the three segments in the thorax of an insect and bears the first pair of legs. Its principal sclerites, exoskeletal plates) are the pronotum(dorsal),  the prosternum (ventral),  and the propleuron(lateral) on each side. The prothorax never bears wings in extant insects, though some fossil groups possessed wing-like projections. All adult insects possess legs on the prothorax, though in a few groups (e.g., the butterfly family Nymphalidae) the forelegs are greatly reduced. In many groups of insects, the pronotum is reduced in size, but in a few it is hypertrophied, such as in all beetles (Coleoptera), in which the pronotum is expanded to form the entire dorsal surface of the thorax, and most treehoppers (family Membracidae, order Hemiptera), in which the pronotum is expanded into often fantastic shapes that enhance their camouflage or mimicry.Similarly, in the Tetrigidae, the pronotum is extended backward to cover the flight wings, supplanting the function of the tegmina.


Prothorax of a coleopteran

- Wikipedia 

LARVA

larva (plural larvae /ˈlɑːrv/) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians or cnidarians typically have a larval phase of their life cycle.
Larva of Papilio xuthus, butterfly
The larva's appearance is generally very different from the adult form (e.g. caterpillars and butterflies.  A larva often has unique structures and organs that do not occur in the adult form, while their diet might be considerably different.
Larvae are frequently adapted to environments separate from adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population.
Animals in the larval stage will consume food to fuel their transition into the adult form. In some species like barnacles, adults are immobile but their larvae are mobile, and use their mobile larval form to distribute themselves.
Some larvae are dependent on adults to feed them. In many eusocial Hymenoptera species, the larvae are fed by female workers. In Ropalidia marginata (a paper wasp) the males are also capable of feeding larvae but they are much less efficient, spending more time and getting less food to the larvae. 
Eurosta solidaginis Goldenrod Gall Fly larva
The larvae of some species (for example, some newts) can become pubescent and do not develop further into the adult form. This is a type of neoteny.
It is a misunderstanding that the larval form always reflects the group's evolutionary history. This could be the case, but often the larval stage has evolved secondarily, as in insects. In these cases the larval form may differ more than the adult form from the group's common origin.

Selected Types of Larvae
AnimalName of larva
Porifera (sponges)coeloblastula larvae (= blastula larvae), parenchymula (= parenchymella), amphiblastula
HeterocyemidaWagener's larva
Dicyemidainfusoriform larva
Cnidariansplanula, actinula
Ctenophoracydippid larvae
PlatyhelminthesGötte’s larva, Müller's larvamiracidium, oncomiracidium, coracidium, redia, cercaria
Annelidanectochaeta, polytroch
NematodaDauer larva
Sipunculapelagosphera larva
Ectoproctacyphonautes, vesiculariform larvae
Nematomorphanematomorphan larva
Phoronidsactinotroch
Cycliophorapandora, chordoid larva
Nemerteapilidium, Iwata larva, Desor larva
Acanthocephalaacanthor
LociferaHiggins larva
Brachiopodalobate larva
Priapulaloricate larva
Certain molluscs, annelids, nemerteans and sipunculidstrochophore
Certain molluscs veliger
Mollusca : freshwater Bivalvia (mussels)glochidium
Arthropoda : †Trilobitaprotaspis (unjointed), meraspis (increasing number of joints, but 1 less than the holaspis), holaspis (=adult) 
Arthropoda: Xiphosurnaeuproöps larva ("trilobite larva")
Arthropoda : Pycnogonidaprotonymphon
Crustaceansnauplius, metanauplius, protozoea, antizoea, pseudozoea, zoea, postlarva, cypris, primary larva, mysis
Crustacea : Decapodazoea
Insecta :  Lepidoptera (butterflies and moths)caterpillar
Insecta : Beetlesgrub
Insecta : Flies, Bees, Waspsmaggot
Insecta : Mosquitoeswriggler
Deuterostomesdipleurula (hypothetical larva)
Echinodermatabipinnaria, vitellaria, brachiollaria, pluteus, ophiopluteus, echinopluteus, auricularia
Hemichordatatornaria
Urochordatatadpole (does not feed, technically a "swimming embryo")
Fish (generally)larva
Fish : Petromyzontiformes (lamprey)ammocoete
Fish : Anguilliformes (eels)leptocephalus
Amphibianstadpole, polliwog
References

  1. ^ Sen, R; Gadagkar, R (2006). "Males of the social wasp Ropalidia marginata can feed larvae, given an opportunity". Animal Behavior 71: 345–350. doi:10.1016/j.anbehav.2005.04.022.
  2. ^ Moore, R.C. (1959). Arthropoda I - Arthropoda General Features, Proarthropoda, Euarthropoda General Features, Trilobitomorpha. Treatise on Invertebrate Paleontology. Part O. Boulder, Colorado/Lawrence, Kansas: Geological Society of America/University of Kansas Press. pp. O121, O122, O125. ISBN 0-8137-3015-5. 

External Links


Bibliography

  • Brusca, R. C. & Brusca, G. J. (2003). Invertebrates (2nd ed.). Sunderland, Mass. : Sinauer Associates.
  • Hall, B. K. & Wake, M. H. (1999, eds.). The Origin and Evolution of Larval Forms. San Diego: Academic Press.

- Wikipedia 

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