The Hemerotrecha banksi group is revised and the status of the genus Hemerotrecha is examined. The female of H. truncata Muma 1951 is described for the first time, and five new species are named: H. hanfordana, H. kaboomi, H. prenticei. H. pseudotruncata, and H. vetteri. Solifuges, new species, distribution, systematics
Keywords:
Abstract.
We attempt to demonstrate that physicians overdiagnose loxoscelism (colloquially known as ‘brown recluse spider bites’) by comparing the numbers of such diagnoses to the historically known numbers of Loxosceles spiders from the same areas in four western American states. The medical community from non-endemic Loxosceles areas often makes loxoscelism diagnoses solely on the basis of dermonecrotic lesions where Loxosceles spiders are rare or non-existent. If these diagnoses were correct then Loxosceles populations should be evident, specimens should readily be collected over the years and there should be a reasonable correlation between diagnoses and spider specimens. In 41 months of data collection, we were informed of 216 loxoscelism diagnoses from California, Oregon, Washington and Colorado. In contrast, from these four states, we can only find historical evidence of 35 brown recluse or Mediterranean recluse spiders. There is no consistency between localities of known Loxosceles populations and loxoscelism diagnoses. There are many conditions of diverse etiology that manifest in dermonecrosis. In the western United States, physician familiarity with these conditions will lead to more accurate diagnoses and subsequent proper remedy. q 2003 Elsevier Ltd. All rights reserved.
Five new species of Solifugae are described from North America: Eremobates chihuaensis, Eremobates gerbae, Hemerotrecha sevilleta, Hemerotrecha cornuta, Eremochelis oregonensis as well as the females of Eremocosta gigasella (Muma, 1970), and Eremobates polhemusi Muma & Brookhart, 1988.
Myrmecomorphs are arthropods that have evolved a morphological resemblance to ants. Myrmecophiles are arthropods that live in or near ant nests and are considered true symbionts. The literature and natural history information about spider myrmecomorphs and myrmecophiles are reviewed. Myrmecomorphy in spiders is generally considered a type of Batesian mimicry in which spiders are gaining protection from predators through their resemblance to aggressive or unpalatable ants. Selection pressure from spider predators and eggsac parasites may trigger greater integration into ant colonies among myrmecophilic spiders.
One species of the genus Masoncus (Araneae, Linyphiidae) is described and illustrated . Masoncus pogonophilus new species has been collected exclusively inside the nests of the Florida harvester ant, Pogonomyrmexbadius (Latreille) (Hymenoptera, Formicidae) and is, therefore, considered a myrmecophile, or obligate ant associate. Morphological characters separating this new species from two of the three described congeners(M. arienus and M. conspectus) are noted .
After constructing their vertical triangle-webs, Hyptiotes cavatus (Hentz) tense them by reeling in monitoring line thread and holding it between their second and third legs . When a prey strikes its web, a spider releases this slack silk, suddenly reducing web tension and causing the web to shake (Lubin 1986; Opell 1982) . This behavior may also change the properties of the web's cribellar capture threads that extend across its four diverging "radii ." Like the cribellar threads of other uloborids, those of H. cavatus are composed of torus shaped puffs of fine cribellar fibrils deposited around supporting axial fibers (Fig. 1 ; Opell 1989a) . The reduction of web tension that occurs when spiders respond to prey may increase the width of these cribellar puffs, thereby exposing more surface area per unit length of cribellar thread and increasing its ability to hold prey . To determine if this occurs, we measured the properties of taut and slack cribellar threads of H. cavatus .
When disturbed, Uloborus glomosus either remain in position at the hub of their orb-webs, jump from the web, move to the edge of the web, or shake the web . The time of day influences which of these behaviors is expressed . Spiders tend to jump in the afternoon and the evening but not in the morning . In the morning they tend to move to the edge of the web or remain in position . The tendency to shake the web is approximately the same throughout the day. Ambient temperature appears not to be the principal factor explaining the differences in jumping, moving to the edge, and remaining in position . Historical differences in the activity patterns of various spider predators may have influenced the time-related expression of disturbance behavioral patterns.
