Clark W. Beasley

Altitudinal Distribution of Tardigrada of New Mexico with the Description of a New Species

-Nineteen species of Tardigrada are reported from New Mexico, including the description of Hypsibius macrocalcaratus n. sp. Only one species had been previously reported from this state. Altitudinal distribution of the reported species is considered.

Doryphoribius mexicanus, a new species of Tardigrada (Eutardigrada: Hypsibiidae) from Mexico (North America)

ABSTRACT A new eutardigrade, Doryphoribius mexicanus, new species, is described from a moss sample collected in Mexico. The new species is most similar to D. bertolanii Beasley & Pilato, 1987 but differs from it by different configuration and lengths of the macroplacoids, longer secondary branches of claws in the respect to the primary branches and some other morphometric characters.

Photokinesis of Macrobiotus hufelandi (Tardigrada, Eutardigrada)

Abstract Macrobiotus hufelandi Schultze, 1834 was tested for response to light. Size groups of less than 120 m and of 120 m or more were used. It was found that the smaller, younger size group exhibited a statistically significant negative response to light. This is hypothesized to function in conservation of body moisture and be more important to the smaller individuals because of the greater surface area-to-volume ratio. An experiment on response to gravity was done in an effort to determine if the negative photokinesis was the total result of a more complex type of behavior but this experiment did not detect any significant response to gravity in either of the size groups. Observation of the bacterial trails left by the tardigrades indicates that this behavior is not negative phototaxis, but rather negative photokinesis which is a non-directed, random movement in which the animal either increases its speed or changes its direction when exposed to light.

The first record of the genus Haplohexapodibius Pilato & Beasley, 1987 in Africa, with notes on synonymy of Hexapodibius beasleyi Maucci, 1988, with Haplohexapodibius seductor Pilato & Beasley, 1987

ABSTRACT Notes on the synonymy of Hexapodibius beasleyi Maucci, 1988, with Haplohexapodibius seductor Pilato & Beasley 1987, are given. Ha. seductor Pilato & Beasley, 1987, is a new record for the African tardigrade fauna.

Redescription of Doryphoribius zyxiglobus (Horning, Schuster & Grigarick 1978) (Eutardigrada: Hypsibiidae) and extension of its geographic range

Abstract A rare species, Doryphoribius zyxiglobus, was found in mosses in New Zealand. So far, it has been cited only three times; from Australia, New Zealand and central China. The original description is very brief and is insufficient by todays taxonomic standards and seems not to be based on the holotype. A photograph of the slide mounted holotype (obtained from The Museum of New Zealand) showed it to be so poorly preserved and oriented that it was deemed probable that little would be gained by its further examination. Consequently, the redescription was based on a few limited measurements from the photograph of the holotype with a complete set of measurements of a paratype and supported by morphometric analysis of a set of topotypes—all borrowed from The Museum of New Zealand. A comparison between sets of specimens from three countries (New Zealand, Australia and China) and a single specimen from South Africa permitted an evaluation of the geographic variation of this species. This paper thus redescribes D. zyxiglobus, reports on populations from widely separated locales and extends its geographical range.

A new freshwater Tardigrada Dactylobiotus kansae sp. n. (Eutardigrada: Parachela: Murrayidae) from Kansas, U.S.A

Abstract A new eutardigrade, Dactylobiotus kansae, new species, is described from a freshwater algal sample from Kansas, U.S.A. The new species differs from other species of this genus by having a smooth cuticle, shorter stylet support insertion point distance, and smooth eggs deposited in the exuvium.