New Notiodes semiaquatic weevil (Curculionidae) from sporocarps of Marsilea mollis (Marsileaceae) in southern Arizona, USA

A new species from the semiaquatic weevil genus, Notiodes sporocarpicus, which develops and pupates in the sporocarps of the water fern Marsilea mollis B.L. Rob. & Fernald, is described from cattle tanks in southeastern Arizona. This new species can be separated readily from the majority of the known species by its nearly straight rostrum, with its distinctive dorsally swollen base and attenuated apex. Its elongate and slender body will separate N. sporocarpicus from most species in the genus except N. aeratus, which lacks the characters above. The Texas species N. celatus resembles the new species but has strongly developed suberect curved setae that are not present in N. sporocarpicus. Included are habitus photos and line drawings of the male and female genitalia of the new species.     

Herbivorous and parasitic insect guilds associated with Great Basin wildrye ( Elymus cinereus ) in southern Idaho

Insects inhabiting Great Basin wildrye ( Elymus cinereus Scribn. & Merr.) were surveyed at two sites on the Snake River Plain in southern Idaho during 1982 and 1983. Forty-six species of phytophagous insects were observed. In addition, eight parasitoid species were reared from insect hosts in the plant culms and identified. Lifestage, abundance, plant part utilized, and study site were recorded for each insect species collected. Insect guilds at the two sites were compared based on species presence utilizing Sorensen's similarity index. Overall, 26 insect species were common to both sites, yielding a moderate similarity index of 0.62. The majority of the species that constitute the wildrye herbivore guilds were oligophagous (restricted to grasses). Many of these insects feed on grain crops as well as other native and introduced grasses. The relatively high diversity of phytophages on wildrye may be due to its tall, bunchgrass growth form, its abundance within its habitat, its broad geographic range, and the large number of related species of grasses in the region.     

Ants from northern Arizona and southern Utah

Ants of 22 species were collected in can pit-traps from 16 different vegetative associations to determine distribution, seasonal and annual occurrence, and population as bases for monitoring environmental impact. Thirteen species were sufficiently abundant and distributed to qualify as indicator species. Myrmecocystus mexicanus was the most widespread ecologically. Pogonomyrmex occidentalis was the most abundant species, but second in ecological distribution. The greatest number of species was found in the juniper- Ephedra -grass association, and the fewest species in Ephredra-Coleogyne-Grayia.        

Factors associated with wetwood intensity of Populus fremontii (Fremont cottonwood) in Arizona

Wetwood is a condition of Populus fremontii and other tree species characterized by staining and water soaking in the heartwood, bleeding from wounds and stem junctions, and leaf and branch dieback. A field survey indicated that wetwood symptoms were present in populations of Populus fremontii at all 17 riparian sites survived in Arizona. However, incidence and severity of bleeding systems varied within and among sites. Within sites, incidence and severity increased with tree size. In the smallest size class of trees (1-32 cm dbh), incidence (% of trees with wetwood bleeding symptoms) ranged among sites from 14% to 83%, and mean severity ranged from 1.1 to 2.6 (on a 5-point scale). Closer host spacing (i.e., greater density), more homogenous stand composition, finer substrate texture, and channel instability all were significantly correlated with increased expression of wetwood symptoms. Bleeding symptoms also were significantly correlated with canopy effects. As the severity of bleeding symptoms increased, so did canopy decline independent of changes in host density.     

Genetic analysis of the rare species Salix arizonica (Salicacea) and associated willows in Arizona and Utah

Management decisions affecting the rare plant Arizona willow ( Salix arizonica ) will be aided by understanding genetic similarities among populations of this species. Random Amplified Polymorphic DNA (RAPD) analysis was conducted on 20 populations of S. arizonica , 12 populations of 5 congeners, and 2 samples of outgroup, Populus tremuloides . A phenogram based on DNA markers shows clear separation of populations of S. arizonica from those of co-occurring willow species, but similarity is low (～ 37%) between Utah and Arizona populations of S. arizonica . Evaluation of the relationship of habitat characteristics and geographic distance to genetic similarity reveals that environment and genetic similarity are poorly correlated. Considering Arizona versus Utah populations, we found a significant negative relationship between geographic distance and genetic similarity ( r = 0.936), but no significant relationship between interpopulation distance and genetic similarity within Arizona or Utah. The wide geographic disjunction of S. arizonica populations in Utah and Arizona appears to have existed for a long period during which genetic drift, random mutations, and selection for somewhat different habitats have pushed the 2 regional complexes along separate evolutionary trajectories. Preservation of genetic variation within S. arizonica will require protection of multiple populations in Arizona and Utah.     

Beetles from the environs of Lake Powell in southern Utah and northern Arizona

Sixty-eight species of beetles of 14 families were collected in pit traps in 12 major vegetative communities during environmental monitoring studies in the summers of 1971 to 1973 in southern Utah and northern Arizona. Seasonal and plant community differences and correlations in population and composition were noted for the 16 sites studied. Highest populations and the most species were found in a grass community, but occurred in different months in each of the three years. Lowest populations were found in a Coleogyne community, and fewest species in an Artemisia- grass community.     

Caddisfly (Trichoptera) assemblages along major river drainages in Arizona

Seventy-two caddisfly species in 36 genera and 15 families were collected along the Little Colorado, Verde, Gila, and Colorado rivers in Arizona. Brachycentrids, hydropsychids, limnephilids, and uenoids made up nearly 50% of the assemblage in forested sites above 2200 m. Hydropsychids, hydroptilids, and leptocerids made up 75% of the assemblage in grassland watersheds between 2200 and 1000 m, and 80% at sites below 1000 m in desert watersheds. Species richness averaged 16 at sites above 2200 m elevation, 7 between 2200 and 1000 m, and 3 below 1000 m. H' diversity was typically >3 at sites above 2200 m and <2.5 below 2200 m. Each river had distinct faunas likely due to isolation of drainages across semiarid landscapes. Low S&oslash;rensen similarity values were measured for caddisfly assemblages in the highly regulated Colorado River and the other 3 rivers. Only 17 species were collected at 14 sites along 700 km of the Colorado River. Indicator caddisfly species are provided for altered and less disturbed drainages. We added 7 species not previously reported in Arizona for a total of 154 caddisfly species in the state. We provide a baseline of caddisfly indicators for monitoring changes in ecosystem health during the predicted long-term drought and population expansion in southwestern USA.     

Range extension of Helianthus spp. (Asteraceae) in Arizona and Utah

Two populations of Helianthus niveus (Benth.) Brandegee ssp. canescens (A. Gray) Heiser were discovered in northern Arizona extending the range 300 miles north for this species. Helianthus deserticola Heiser range was extended 100 miles east in both Arizona and Utah.     

Observations on the dwarf shrew ( Sorex nanus ) in northern Arizona

Observations of 23 dwarf shrews ( Sorex nanus ) at Fracas Lake in Arizona extend the range of this uncommon shrew northward on the Kaibab Plateau and provide further information regarding the ecology and habitat requirements of this species. Shrews were captured in a previously unreported habitat type (Rocky Mountain montane conifer forest; Brown 1982). This study illustrates the usefulness of intensive, long-term studies and faunal surveys using pitfall traps.     

Flood flows and population dynamics of Arizona sycamore ( Platanus wrightii )

Platanus wrightii is a pioneer tree species of warm-temperate riparian deciduous forests in southwestern United States and northern Mexico. Dendrochronological analysis of populations in central and southern Arizona indicated that P. wrightii seedlings establish episodically. Long intervals (10-40 years) elapsed with no apparent establishment. Seedling establishment years were positively associated with winter flood size and annual flow rate, and weakly negatively associated with summer flood size. Large floods sometimes preceded multi-year establishment waves. During the past 2 decades an abundance of winter floods and very wet springs has allowed frequent establishment of P. wrightii . For example, plants established at many sites during the winter flood years of 1993 and 1995, particularly along channels scoured and widened by flood waters. Platanus wrightii also reproduces asexually. Ramets were more abundant than genets in all populations, and ramets established more frequently than seedlings. Ramet density (mean number per genet) varied widely between populations, from 2 (Huachuca Canyon) to 9 (Haunted Canyon), and increased with tree size within 4 of 9 populations. Population size structure varied across a gradient of watershed area. Populations along streams draining the largest watersheds had an abundance of small trees (mean trunk diameter of P. wrightii is influenced by temporal as well as spatial differences in stream flow regimes.     

Agropyron arizonicum (Gramineae: Triticeae) and a natural hybrid from Arizona

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The new hybrid X Agrositanion pinalenoensis (Gramineae: Tribe Triticeae) is found in disturbed, forested areas of higher elevations in southern Arizona. In the Pinaleno Mountains where logging has been heavy, numerous disturbed habitats have permitted frequent hybrid populations to persist. Intermediate phenotype, chromosome behavior, lack of seed set, and pollen sterility were used to interpret the status of this hybrid derivative. Introgression and/or segregation are not apparent. &nbsp;     

Virginia opossum ( Didelphis virginiana virginiana ) from Yavapai County, Arizona

The Virginia opossum ( Didelphis virginiana ) is the only marsupial native to the United States. In recent times, D. virginiana has expanded its range through natural movements and anthropogenic introductions. Didelphis virginiana has been present in southern Arizona owing to range expansion by the Mexican subspecies ( D. v. californica ) and anthropogenic introductions of the eastern subspecies ( D. v. virginiana ). Here, we document the recent collection of an opossum in central Arizona. We also discuss how it possibly moved there and report on its stomach contents at the time of collection. El tlacuache norte&ntilde;o ( Didelphis virginiana ) es el &uacute;nico marsupial nativo de Estados Unidos. En tiempos recientes, D. virginiana ha expandido su &aacute;rea de distribuci&oacute;n tanto por movimientos naturales como por introducciones antropog&eacute;nicas. Didelphis virginiana se ha encontrado en el sur de Arizona debido a la expansi&oacute;n de la subespecie mexicana ( D. v. californica ) y a introducciones antropog&eacute;nicas de la subespecie oriental ( D. v. virginiana ). Aqu&iacute; documentamos la colecta reciente de un tlacuache en el centro de Arizona. Tambi&eacute;n discutimos c&oacute;mo podr&iacute;a haber llegado hasta all&iacute; e informamos sobre los contenidos de su est&oacute;mago al tiempo de la colecta.     

Observations on mermithid parasitism (Nematoda: Mermithidae) in two species of Lasius ants (Hymenoptera: Formicidae)

The morphological effects of nematode parasitism by Pheromermis myrmecophila were investigated in two species of ants, Lasius flavus and Lasius niger, collected on Clare Island, Ireland. Infected males and queens were found for L. flavus but only infected queens in L. niger. The numbers of nematodes present in each infected specimen were counted and their lengths were measured. Head width, femur length and wing measurements were made for infected and non-infected individuals of both species. In queens, the length of the nematodes decreased as the number per ant increased. When single nematodes were present their mean lengths were significantly greater in L. flavus than in L. niger. In addition to the reduction in wing size for all parasitized specimens, head widths and femur lengths of the queens were significantly different in both species. A log–log graph of radial cell length versus width suggested a linear reduction of wing size.     

Recurrence of Mexican long-tongued bats ( Choeronycteris mexicana ) at historical sites in Arizona and New Mexico

The Mexican long-tongued bat ( Choeronycteris mexicana ) is a nectar-eating species that seasonally inhabits the southwestern United States. Since 1906, fewer than 1500 individuals of C. mexicana have been documented throughout the range of the species. We conducted a field survey in Arizona and New Mexico during summer 1999 to check historically occupied areas for recurrence of C. mexicana . We observed C. mexicana occupying a majority (75%, n = 18) of visited sites. Multiple individuals were observed at many sites, including young-of-year. Choeronycteris mexicana roosted in lighted areas close to entrances within mine adits, abandoned buildings, wide rock crevices, and caves. All occupied sites in Madrean evergreen woodlands or semidesert grasslands where species of Agave were present. Most sites were located near a water source and, with the exception of a single site, near areas of riparian vegetation. Sites at which we did not encounter C. mexicana were frequently disturbed, difficult to search, or historically occupied by single individuals. Based on the relatively high rate of bat recurrence, we do not believe that populations of C. mexicana in the region have declined dramatically over the past several decades.     

Fate and characteristics of Picea damaged by Elatobium abietinum (Walker) (Homoptera: Aphididae) in the White Mountains of Arizona

Spruce aphid, Elatobium abietinum (Walker), is a new invasive pest in high-elevation forests of southwestern USA. Plots in the White Mountains of Arizona were evaluated over several years to assess the extent and severity of damage in high-elevation forests and to identify tree and site characteristics associated with defoliation and mortality. Large areas were defoliated in each of 4 recent outbreaks. Impact from a single defoliation episode included an overall mortality of 10.3% to Picea engelmannii Parry, 24%-41% in severely defoliated trees. Defoliation severity was much greater on P. engelmannii than on P. pungens Engelm. and was more severe in the lower canopy layers. Retention of foliage in the upper-crown third of individual trees was a critical factor in tree survivorship. Mortality was associated with defoliation severity and severe infection by Arceuthobium microcarpum (Engelmann) Hawksworth & Wiens. Picea pungens was much more susceptible to A. microcarpum more than was P. engelmannii . The combined effects of high levels of defoliation and mistletoe infection were lethal, resulting in almost 70% mortality. Mortality continued to occur at 3 years after defoliation. This aphid will affect natural disturbance regimes and tree population dynamics in mixed-conifer and spruce-fir forests of the American Southwest.     

A seed chalcid ( Eurytoma squamosa Bugbee) parasitizes buckbrush ( Ceanothus fendleri Gray) seeds in a ponderosa pine forest of Arizona

Predispersal seed parasitism rates were quantified for buckbrush ( Ceanothus fendleri Gray) in 3 Arizona ponderosa pine ( Pinus ponderosa Laws.) forest units that had been thinned for ecological restoration objectives. The chalcidoid wasp Eurytoma squamosa Bugbee (Eurytomidae) was responsible for 35% of total seed loss in a single year. These findings represent an expansion of the known range and host list for E. squamosa and increase our understanding of factors that may constrain regeneration of C. fendleri in Southwest ponderosa pine forests.     

Seed production and seedling establishment of a Southwest riparian tree, Arizona walnut ( Juglans major )

A four-year study of five populations has revealed influences on seed production and seedling establishment of the Southwest riparian tree Juglans major . Germination is abundant after production of large seed crops (masts), but masts are produced infrequently. Within years, germination is stimulated by summer rains, enabling seedlings to establish on riparian terraces as well as streambanks. Traits such as capacity for dormancy during summer drought allow some seedlings to survive on terraces, but abundant rainfall is essential for high rates of seedling success. Ranges of moisture tolerance vary among seeds collected from different populations, suggesting that ecotypes may exist between riparian sites with dissimilar moisture regimes. Population-based differences are associated, in part, with differences in seed size.     

Selection of dwarf mistletoe-infected ponderosa pines by Ips species (Coleoptera, Scolytidae) in northern Arizona

Following an Ips bark beetle outbreak in 2002, mortality of ponderosa pine ( Pinus ponderosa Douglas ex C. Lawson) was evaluated in 2 study areas infested with southwestern dwarf mistletoe ( Arceuthobium vaginatum [Willd.] Presl subsp. cryptopodum [Engelm.] Hawksw. & Wiens) in the Coconino and Tonto National Forests, Arizona. A pairwise comparison of dwarf mistletoe ratings for live and dead ponderosa pines was conducted to determine whether dead ponderosa pines had higher dwarf mistletoe ratings than pines that were not attacked. In both study areas, dead ponderosa pines had significantly higher dwarf mistletoe ratings, indicating an association between the severity of dwarf mistletoe infection and susceptibility to attack by Ips spp. We suggest that the probability of ponderosa pine mortality is greater in stands severely infested with southwestern dwarf mistletoe in northern Arizona.     

Evidence of a parasite protist in Eurhomalea lenticularis (Sowerby, 1835) (Mollusca: Bivalvia): A case of intraoocytarian parasitism

In the present paper a microsporidian parasitic protist is described and characterized; it was observed in oocytes of Eurhomalea lenticularis Sowerby. The clams were obtained in Algarrobo, Chile (33°20′S, 71°40′W). The observations were made on 5?µm sections of female clam gonads, processed by routine histological techniques with ARTETA trichromic stain. According to the parasite's characteristics, it is established that the microsporidian protist is related to the genus Steinhausia (Chytridiopsidae). Microsporidian prevalence reached 20.6% (n?=?34) in summer months, but there was no evidences of cell damage in the oocyte of the host; in a total of 66 female clams, a 10.6% of infection was detected between December 1995 and August 1996. The infection intensity showed that 77.4% of the infested acini had single parasitized oocytes, and 88.0% of total oocytes parasitized contained only one cyst in the cytoplasm.