A review of described Metacyrba, the status of Parkella, and notes on Platycryptus and Balmaceda : with a comparison of the genera (Araneae: Salticidae: Marpissinae)

Parkella Chickering 1946 = Metacyrba F. O. P.-Cambridge 1901, n. syn.; Parkella venusta Chickering 1946 = Metacyrba venusta (Chickering 1946), n. comb.; Parkella fusca Chickering 1946 and Dendryphantes franganilloi Caporiacco 1955 = Metacyrba venusta (Chickering 1946), n. syn. The six valid described species of Metacyrba are diagnosed and re-illustrated to show previously unrecognized genitalic differences. Metacyrba similis Banks 1904 is resurrected as a subspecies, becoming Metacyrba taeniola similis Banks 1904, n. status. The female of Metacyrba pictipes Banks 1903 is described for the first time. Metacyrba arizonensis Barnes 1958 = Platycryptus arizonensis (Barnes 1958), n. comb., and Marpissa magna (Peckham & Peckham 1894) = Platycryptus magnus (Peckham & Peckham 1894), n. comb. Platycryptus broadwayi (Peckham & Peckham 1894) = Platycryptus magnus (Peckham & Peckham 1894), n. syn. [lectotypes and paralectotypes are designated for both names]. Metacyrba nigrosecta (Mello-Leitão 1945) = Balmaceda nigrosecta Mello-Leitão 1945, comb. restored. The genera Balmaceda Peckham & Peckham 1894, Metacyrba, and Platycryptus Hill 1979 are compared morphologically among themselves and to Breda Peckham & Peckham 1894 and Fuentes Peckham & Peckham 1894. The distributions of Balmaceda picta Peckham & Peckham 1894 and Metacyrba species are updated. Marpissa melanura F.O.P.-Cambridge 1901 is resurrected; it is not a synonym of Marpissa minor F.O.P.-Cambridge 1901 nor Platycryptus californicus (Peckham & Peckham 1888)

A review of the Nearctic jumping spiders (Araneae: Salticidae) of the subfamily Euophryinae north of Mexico

The generic and specific composition ofthe Nearctic jumping spiders ofthe subfamily Euophryinae north of Mexico is reviewed, and the biogeographic affinities of the constituent groups are diagnosed. The five North American species of HabrocestUln are removed from that non-euophryine genus; four are placed in the New Genus Naphrys, type species Habrocestum acerbum Peckham & Peckham 1909, creating the following New Combinations: Naphrys acerba (Peckham & Peckham), Naphrys bufoides (Chamberlin & Ivie 1944), Naphrys pulex (Hentz 1846), and Naphrys xerophila (Richman 1981). The fifth species is not an euophryine, and becomes Chinattus parvulus (Banks 1895), New Combination. Four species placed in the genus Tylogonus, another non-euophryine genus, are removed to the New Genus Mexigonus, type species Sidusa minuta F.O.P.-Cambridge 1901, creating the following New Combinations: Mexigonus arizonensis (Banks 1904), Mexigonus dentichelis (F.O.P.-Cambridge 1901),Mexigonus minutus (F.O.P.-Cambridge), and Mexigonus morosus (Peckham & Peckham 1888). One of the two species of Nearctic Euophrys has been misplaced, and becomes Chalcoscirtus diminutus (Banks 1896), New Combination. New state records are reported for Chalcoscirtus diminutus [Kansas, Michigan, Minnesota, Missouri, Nebraska, New Mexico], Mexigonus minutus [California], Naphrys acerba [New Mexico], and Pseudeuophrys erratica (Walckenaer 1826) [New York]. Of the eight known euophryine genera with Nearctic representatives, Anasaitis (one species) and Cory thalia (two species) are considered Neotropical in origin, whereas Chalcoscirtus (three species), Ezwphrys (one species), and Talavera (one species) are considered Holarctic. The Palaearctic Pseudeuophrys erratica is introduced. The affinities of the apparently endemic Nearctic Naphrys (four species) and Mexigonus (four species) are uncertain at this time. Although not an euophryine, the presence of a species of Chinattus in eastern North America is biogeographically interesting, as the other species in the genus are Asian; it joins a diversity of taxa with this distribution

A synonym in the genus Fluda (Araneae: Salticidae)

A synonym in the genus Fluda (Araneae: Salticidae

Cory thalia canosa (Araneae: Salticidae) reassigned to Anasaitis

Four species of Cory thalia C.L.Koch 1851 were reported by Richman & Cutler (1978) to occur in North America north of Mexico. Subsequently, one of these four species, C. delicatula Gertsch & Mulaik 1936, was synonymized with Euophrys dim in uta (Banks 1896) (Edwards 1980). Of the three remaining species, only two species can validly be placed in the genus. These are C. conspecta (Peckham & Peckham 1896) and C. opima (Peckham & Peckham 1885), the northernmost species in the genus, both with reported distributions ranging from Central America to Arizona

A new species of Neonella (Araneae: Salticidae) from southeast Florida

A new species of Neonella is described that has a distribution apparently restricted to the southeast coast of Florida. So far, it has only been found in Brevard and Monroe counties. It is closely related to N. mayaguez Galiano from Puerto Rico

Baryon Spectroscopy on the Lattice

Recent lattice QCD calculations of the baryon spectrum are outlined.Comment: Plenary contribution to Baryons 2002, Jefferson Lab, March 2002, 9 pages, 7 figure

Topology and chiral symmetry in finite temperature QCD

We investigate the realization of chiral symmetry in the vicinity of the deconfinement transition in quenched QCD using overlap fermions. Via the index theorem obeyed by the overlap fermions, we gain insight into the behavior of topology at finite temperature. We find small eigenvalues, clearly separated from the bulk of the eigenvalues, and study the properties of their distribution. We compare the distribution with a model of a dilute gas of instantons and anti-instantons and find good agreement.Comment: 3 pages with 3 ps figures; to appear in the proceedings of Lattice '99, Pisa, Italy, June 29 -- July 3, 1999. LATTICE99(topology

Use of reaction wheels and nonlinear control for a satellite scanning a small celestial area

Reaction wheel control torque for satellite system scanning of small celestial are

Determination of pilot and vehicle describing functions from the Gemini 10 mission

Three types of manual control maneuvers conducted during the Gemini-10 mission have been analyzed in order to measure and document the describing function of the pilot, the vehicle and the pilot-vehicle combination during an actual space mission. Measurements made from the data records of the reentry maneuver (a single axis control task) indicate that the pilot's control behavior changes during critical portions of the reentry. Measurements made of the deorbit maneuver and of a terminal phase initiation maneuver (three axis tasks) show that the pilot assigns priorities to the separate axes and controls them differently. His control technique is also influenced by the magnitude of the thrust disturbance present during the maneuvers. The results for all three types of maneuvers show that the pilot adapts to the nonlinear spacecraft control system in such a way that the combined pilot-vehicle dynamics take the form of the linear crossover model