Harvestmen

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The abdomen consists of 10 segments but they can only be distinguished in the most primitive suborder Cyphophthalmes. In other harvestmen, only 9 are visible. Harvestmen have only two eyes, which in most species are located on an elevation—the eye tubercle—on top of the cephalothorax. The two eyes are positioned on either side of the eye tubercle. The upper jaws, the chelicerae, have three segments. The two outermost form a pincer claw. The lower jaws, the pedipalps, resemble small legs and lack pincer claws.

The very long legs are originally seven-segmented. However, the outermost segment has become subdivided into many small segments. The outermost of these is furnished with a claw. Of the legs, the second pair is usually the longest. They also function as sensory organs. In contrast to true spiders, harvestmen lack book lungs. Their oxygen supply therefore occurs solely via tracheae. These open with two spiracles at the front of the underside of the abdomen. Long-legged species furthermore have one spiracle on the upper and lower side of the tibia segment.

For defense against predators, harvestmen have scent glands whose ducts open above the base of the second pair of legs. Females have a long extrudable ovipositor. Males have a very long penis. Hairs and spines vary greatly. Their number, form, and localization are important systematic characteristics.

Harvestmen occur in just over 3000 species distributed throughout the world. Most live in warm climates. In Sweden, only about 20 species occur. They feed mainly on animal foodstuffs such as insects, spiders, mites, pseudoscorpions, snails and the like. But they can also eat vegetable food such as seeds, fruits, and fungi. The enemies of harvestmen consist of larger insects, spiders, frogs, toads, birds, lizards, dragonflies, and shrews. If a leg becomes caught, it can very easily be shed—so-called autotomy. However, no new leg grows back. The aforementioned secretion from the scent glands also serves as a defense, which has a disgusting vinegar-like odor.

Unlike true spiders, sperm transfer in harvestmen occurs directly from the male to the female genital opening. No kind of courtship seems to occur either. Copulation itself happens in the peculiar manner that male and female meet forehead to forehead. And here it is clearly size that matters. To stand in this position, the male extends his long penis between the female's chelicerae and all the way into the female's genital opening. Copulation is over in a few seconds.

Females have a very long ovipositor with which they lay their eggs in some crevice such as cracks, under stones, or in wood. 2–3 clutches can be laid with a total of a few to several hundred eggs during a season. When the eggs hatch in spring, the millimeter-sized young make their way out by using the sturdy egg tooth located just in front of the eye tubercle. The young become fully developed in late summer or autumn after 6–7 molts. Some harvestmen live on the ground, others on vegetation, on tree trunks, house walls, and the like. They hunt food mostly at night or in twilight.

Gunnar Bakken

This Year's Butterfly Finds from Gästrikland 1995 (Lepidoptera)

Clas Källander
Husbygård, Husbyborg, 75592 Uppsala.

It is time for the fourth annual compilation of butterfly finds from Gästrikland. To my dismay, I have now noted for two years in a row that my reports have been published only after the next year's butterfly season is over. Most unsatisfactory! I shall therefore try to improve myself! This year's contribution is for this reason being written already by Christmas. A likely result of this is that I have not yet managed to receive all lists from other butterfly enthusiasts. This year's report therefore risks being more incomplete than previous years', and the collection of reporters becomes more monotonous than usual. For next year, I therefore wish that you try to send your find data to me or Göran no later than December! I report finds of all butterfly groups except butterflies, which as usual will be treated by Johan Höjer.

Since 1993, there has been a national list of threatened or vulnerable insects, "Red-listed invertebrates in Sweden" (Ehnström et al 1993). This list has been compiled by the Database for Threatened Species, which is a joint unit of the Swedish Environmental Protection Agency and the Swedish University of Agricultural Sciences. One of the intentions of Agenda 21 is that each region shall moreover establish its own red lists. The responsibility for this lies with the provincial governments. A regional list of butterflies has been established for the ABC region, and we ought soon to take the initiative to try at least to compile a proposal for a red list for the X region. One of the motives for the work of collecting information about butterfly finds is to obtain material for this type of list. It is important to find out which species exist, where they exist, and whether they are increasing or decreasing. I therefore report all observations that provide new information about species that are included on any of the red lists, and furthermore for all species that I suspect are decreasing or disappearing in our areas. The systematics, nomenclature, and numbering of the species in this report follow Catalogus Lepidoptorum Suecia (Svensson et al 1994), and Swedish names are given according to Svensson and Palmqvist (1990).

The butterfly summer of 1995 was somewhat unusual both for Gästrikland and the rest of northern Europe. The season began quite normally with snowmelt at the end of March. On 23 March, I made the season's first butterfly find, a female of Depressaria pimpinellae (parsnip webworm), which fluttered restlessly at Rås kitchen window in Mårtsbo. The first half of April followed the calendar fairly well. On 12 April, a number of spring species such as Apocheima pilosaria (hairy geometer), Biston strataria (brownish winter moth), Brachionycha nubeculosa (spring gothic), Orthosia populeti (poplar lutestring), Orthosia incerta (uncertain lutestring), Orthosia gothica (hebrew character), and Cerastis rubricosa (rosy marsh moth) were already on the wing. Then came the setback; below-freezing temperatures and regular recurring snow squalls right up to 15 May. With the exception of a brief warm spell during Whitsun week, the weeks continued with temperatures below normal. By that point the season was considerably delayed. Selenia dentaria (lunar thorn), Odontopera bidentata (scalloped hazel), Phragmtobia fuliginosa (ruby tiger), and Nycteola revayana (oak tree lichen) were still flying, for example, at the beginning of July in Grinduga, which is hereby designated as this year's

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