Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 51. (Budapest 1959)
Kovács, L. ; Gozmány, L.: Data to the quantitative relations of the Lepidoptera of the Alderwood Marshes in Ócsa, Hungary
1. E. bistortata on 1 July, with a rather low dominancy value. This species has also a spring generation, observed by us during our informational 1953 surveys two times in April, with a high d value on both occasions yet with rather low individual numbers ; 2. Ae. punctulata on 8 July, also with a similarly low d value. It also has another, springtime generation, observed by us in 1953 ; its d value was low at that time ; 3. S. dimidiata on 18 September, of a medium d value and individual numbers. Both generations of this species flew during the period of the surveys. It is now time to raise the question whether the picture received on the basis of 14 surveys of dominancy relations would not basically alter, had the surveys been continued uninterruptedly and with an unchanged intensity during the whole season. In this connection, we have to state, in the possession of informational and control surveys made in the first part of 1953 but also of other data gathered at other places and times, that, in essentials, it would not. — P. muscerda would maintain its dominancy even so, indeed, E. griseola would also probably be in the first place among the subdominants. P. muscerda, namely, has an eminent place not only at the time of the second generation, — it is on the wing for four weeks also in the spring, at a time when there were no surveys. Of the subdominant species, E. bistortata and Ae. punctulata, indeed, also D. pusaria would indisputably come to the fore by their high individual numbers in the spring ; they would probably precede, as far as d values are concerned, H. ruralis, but hardly E. griseola. Of the late autumnal species, 0. burmata occurs in higher numbers in the alderwood marshes of Ocsa, yet its d value would probably be low as related to the annual mean. The time of aspect changes could well be established during the period of the surveys, by the data of our collectings. In this regard, the summer months can be divided into three phases. In the first phase, the dominant is the first generation of P. muscerda, in the second, the sole generation of E. griseola, in the third, the second generation of P. muscerda, — or these species attain at least a high d value. The first phase, which begins, on the basis of the data of our surveys in 1953, already at the end of May, lasts till the end of June. Of this period, including also the year 1953, we have at our disposal the results of three surveys and various other collectings. In two of the surveys, P. muscerda was the dominant, in the third, H. ruralis. P. muscerda, however, has always an eminent role, so that we may regard the whole period as a single aspect. This is a transitional period between the spring and summer aspects and lasts for wellnigh two months. Due to the leading role of the above lepidoptera species, we may call it the muscerda —ruralis —metaxella aspect, which is enough to distinguish it from the second muscerda aspect. It is E. griseola which leaves its mark on the following aspect, whilst the former three species will partly be thrust into the background, and partly have a subordinate role. This phase lasts from the turning of June —July till the beginning of August. In its duration, E. griseola is a dominant on four occasions and a subdominant on two further ones, when E. bistortata, that is, Ae. punctulata, dominate. This is the real summer aspect, the richest in species, which, owing to the leading species, we may call the griseola aspect, or, more completely, the griseola —bistortata —punctulata aspect.
