Pyrrhocoris apterus

Another developmental hormone is the juvenile hormone, which predominates early in larval life later ecdysone predominates. It is a methyl ester of the epoxide of a fatty acid derivative, and there is some evidence that its structure differs in different groups of insects. By a series of coincidences, it was discovered that certain paper toweling prevented the European bug, Pyrrhocoris apterus, from developing into sexually mature adults. Instead, an extra one or two larval molts ensued, and all eventually died without being able to complete metamorphosis. The juvenility factor was traced to particular conifers used in American paper pulp, mainly Abies balsamea, Tsuga canadensis, Taxus brevifolia, and Larix laricina. The active principle was isolated and characterized. It... 

However, the pyrrhocorid story certainly fails to justify such a hypothesis. Pyrrhocoris apterus is a native of Europe, and the only plants which produce the (very specific) juvabione are natives of North America. The two simply don t occur together. Further, the bug and all members of its family feed by sucking the juices of weak herbs they are not known feeders of any tree species. What ecological significance is there in the pyrrhocorid story ... 

From the balsam fir tree Abies balsamea, a sesquiterpenoid, juvabione (Figure 9), was isolated as a compound that has a JH activity that causes the last instar larvae of European linden bug, Pyrrhocoris apterus, to molt into nymphal-adultoid forms.58,59 Since then, a number of phytojuvenile hormones have been detected56 such as juvocimene I and II from the sweet basil Ocimum basilicum60,61... 

Experimenting with the insect Pyrrhocoris apterus, Williams and Slama (1966) observed that the insects failed to metamorphose normally in Petri dishes lined with paper of American origin. In elucidating the reason for this chance discovery, they established that Pinaceae used in America as raw material for paper manufacture contain paper factor , a substance of morphogenetic action. This compound, which they called (-I-)-juvabione (11), was isolated by Bowers et al. (1966) and, independently, by Cemy et al. (1967). The members of this latter research group isolated a still more effective derivative, dehydrojuvabione (12) from pinewood. 

Effective doses of these derivatives against Pyrrhocoris apterus and Dysdercus cingulatus are 51 0.5,52 0.01,53 0.000 04,54 0.000 01 and 55 0,000 002 pg/insect. The latter derivative is the most potent juvenile hormone analogue known so far. Only the isomers of S-configuration of this type are active, while those containing... 

Derivative (80) showed medium activity for inhibition of post-ecdysial cuticle sclerotization in Pyrrhocoris apterus. ... 

Wigglesworth [4] confirmed that farnesol and its related compounds showed the juvenoid activity against the bloodsucking bug, Rhodnius prolixus. Slama and Williams [5] found that paper products made from balsam fir, Abies halsamea, showed juvenoid activity against hemipteran bug, Pyrrhocoris apterus, and called the compound the paper factor. The chemical structure of the paper factor was identified as a methyl ester of todomatuic acid, and named juvabione (3) [6]. 

Slama, K. and C. M. Williams, Juvenile hormone activity for the bug Pyrrhocoris apterus, Proc. Natl. Acad. Sci. USA, 54, 411-414(1965). 

Juvebione, paper factor a monocyclic sesquiterpene ester from the wood of the North American balsam fir (Abies balsamea). (-h)-J. is an oil, M, 266, [a] +79.5° (c = 3.5, CHCI3). J. was the first juvenile hormone isolated from a plant, and its structure was the first elucidated. It is specific for Pyrrhocoris apterus and only the dextrorotatory form is biologically active. The search for J. began when it was observed that filter paper made from the wood of the balsam fir contained a factor which produced developmental anomalies in the larvae of Pyrrhocoris. In addition to... 

At the same time, however, the juvenile hormone activity exhibited specifically in the hemipteran bug Pyrrhocoris apterus L. [749] by two constituents of the balsam fir [Ahies halsamea (L) Miller), namely, juvabione (syn. methyl todomatuate), CII, [750] and its dehydroderivative [751], shows that this type of activity, in some insects at least, can reside in sesquiterpenoids arising [137] via the usual biogenetic pathway involving departure of the pyrophosphate function of famesyl pyrophosphate. Actually the isolation from the pulp of... 

Slama K, Williams C M 1966 Paper factor as an inhibitor of the embryonic development of the european bug Pyrrhocoris apterus. Nature 210 329-330... 

Shapes of attachment devices in nature and their hypotheticai evoiutionary pathways (shown as arrows), (a) Bug Pyrrhocoris apterus, smooth puiviiius. (b) Grasshopper Tettigonia viridissima, surface of the attachment pad. (c) Fiy Myathropa florea, unspeciaiized hairs on the ieg. 

The black and orange warning colour of the milkweed bug Oncopeltus fasciatus (Plate 17) is due to part opaque black melanin and part transparent cuticle that allows the underlying pterins to show through. Five different pterins were identified in the red heteropteran fire bug Pyrrhocoris apterus (Plate 9), with erythropterin the most abundant. 

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