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Breisach am Rhein, Germany

Hofmann A.,Verenenweg 4 | Tremewan W.G.,Natural History Museum in London
Entomologist's Gazette | Year: 2010

Based on the biospecies concept, a check-list of the 108 currently recognized species representing die monophyletic genus Zygaena Fabricius, 1775, is provided. Three subgenera are recognized: of these, Mesembrynus Hübner, [1819], is monophyletic, while Agrumenia Hübner, [1819], and Zygaena Fabricius, 1775, are paraphyletic. Three nominal taxa that were originally described as subspecies (two belonging to the Zygaena manlia-group, one belonging to the purpuralis-group, all within the subgenus Mesembrynus) are newly raised to species level, while two (one in the manlia-group, one in Agrumenia) are newly reinstated as valid species. Moreover, eight new combinations are established at subspecies level. Biological/ ecological data and comparisons with other taxa are provided in support of such taxonomie placements.

Two new taxa of the genus Zygaena are described from the Iranian Zagros range: Zygaena mirzayansi sp. n. from the central part of the Zagros and Z. fredi valii ssp. n. from the mountainous regions in the province Kerman. There are observations on the preimaginal biology of the two taxa. For Z. mirzayansi sp. n., the full grown larva is known. It was found on Eryngium billardieri. Zygaena fredi valii ssp. n. feeds on Bupleurum exaltatum (M. Bieb.) or a very close related Bupleurum. The larvae of Z. fredi syntopica, Z. fredi escaleraiana and Z. mirzayansii are figured for the first time. The type-localities of Z. fredi escaleraiana and Z. escalerai have been located more precisely. The types of Z. fredi, Z. fredi escaleraiana, Z. fredi syntopica and Z. mirzayansi are figured.

Hofmann A.,Verenenweg 4 | Kia-Hofmann T.,Verenenweg 4
Entomologist's Gazette | Year: 2010

In the present article, observations of mating strategies of burnet moths in the field and in captivity and the specificity of their natural pheromones and pairings are described and discussed. Moreover, new data on the duration of copulation and the transfer of spermatozoa for a number of species are provided as well as the number of times that an individual modi has been observed to copulate.

With the present article the authors continue their series about pheromone attraction, mating behaviour, ovipositing, egg-batch formation and embryonic development in burnet moths (Zygaena Fabricius, 1775), which began in 2010 (Hofmann & Kia-Hofmann, 2010;2011). The first observations in 2007 of newly hatched L1 larvae of Z. dorycnii araratica Staudinger, 1871.that were attacking and partly or completely eating their unhatched embryonic siblings were followed in 2008-2011 by further intensive and more systematic investigations. It was shown that the majority of investigated species exhibit oophagy and cannibalistic tendencies in the early L1 stage, behaviour that was previously unknown for burnet moths. In all positive experiments only unhatched siblings of the same egg-batch became victims of such attacks (sibling cannibalism, adelphophagy). Cannibalism in stages later than L1, or attacks on other egg-batches was never noticed. In a comparative study of two groups ('cannibs' and 'non-cannibs') we succeeded in quantifying the direct effects and probable benefits of siblicide in combination with cannibalism, behaviour that at first seems counterproductive from an evolutionary point of view. The 'cannibs' L1 larvae were measurably larger and showed some differences in their early behaviour. Moreover, a comparison of the moulting curves of these two groups clearly provided evidence that those larvae that exhibit cannibalism have a time advantage in their development, at least until the third moult. At the beginning of this paper a short introduction and general definitions of cannibalistic behaviour are provided together with specific examples of two Lepidoptera groups 'butterflies' (Rhopalocera) and 'noctuid moths' (Noctuidae), which are followed by our own investigations and a discussion on some evolutionary implications. The authors hypothesise that (1) egg-shell eating, (2) ingestion of infertile eggs and (3) killing and eating unhatched embryos are consecutive evolutionary stages.

Hofmann A.,Verenenweg 4 | Kia-Hofmann T.,Verenenweg 4
Entomologist's Gazette | Year: 2011

Observations on egg deposition by burnet moths have shown that there are principal differences in ovipositing. The formation of regular batches (parquet-like clusters) is described for the first time. New data are provided for 'large batches consisting of several layers' and for 'small batches consisting of a single layer', while the unique way of ovipositing by Z. brizae ('singly-laid eggs') is also described for the first time. With the exception of Z. rosinae, all investigated species place their eggs in a horizontal position, i.e. with the long axis parallel to the substrate. Moreover, there are reliable records of species within the olivieri-group, females of which were observed to place their eggs in a vertical position. The eggs of the remaining species are not only attached to the substrate but are deliberately pressed against it by the female's abdomen and, as a consequence, become deformed, thus producing a characteristic depression on the uppermost side of every egg. This pressure produces a deformation of the eggs that are at the moment of emergence still 'ovoid' but now become compounded together with other eggs into a hexagonal shape. The different shapes of egg batches are described and figured. All non-Palaearctic Zygaeninae deposit their eggs in mono-layered batches. This character is herein regarded as primitive within the genus Zygaena. The most complex order of egg clusters is found in regular batches of several layers with a pyramid-like upward projection, providing shapes that are only found in species of subgenus Mesembrynus. The trigonometric relationships of the basic layer in regular batches are shown. Eggs are deposited in rows, starting at the periphery and going toward the centre, egg by egg; every new egg is staggered by half an egg-length. Thus a fishbone-like structure is produced, when one combines the lines or arrows that result from the sequence of oviposition. As the shells of Zygaena eggs are translucent, the embryonic development from the moment of deposition to the moment of hatching can be observed and is described below. After deposition, the egg consists of two sections, one somewhat opaque, the other translucent. The location of these two phases is dependent on gravity, which is why the lighter section that is translucent moves to one pole in the majority of cases. The opaque part consists of the yolk sack in which the gametes from each parent meet and where the embryo develops. The yolk sack is usually proximate towards the mother and it is at this pole that the micropylar region is situated. After two-thirds of its development, usually after 6-7 days, the first pigmented structures become visible ('the two-dot stage'), the transparent section now being displaced. The entire space within the egg is occupied by the embryo. Hatching occurs at the upper side close to the micropylar region.

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