Philoscia Bonita, a New Species of Isopod Crustacean from Florida

Abstract

Philoscia bonita, new species, was collected from leaf litter around a dwelling in West Hollywood, Florida, on July 5, 1960, and again on February 27, 1961. The species is described and some aspects of its general biology, male-female ratio, length and number of young, are discussed. A new species of the genus Philoscia was found in abundance in leaf litter around dwellings in West Hollywood, Florida. It was active and difficult to catch, and was collected in association with Cubaris murina, Porcellionides pruinosus and Trichorhina donaldsoni Schultz (1963). The new species was found near the soil in leaf litter, not among the twigs and leaves with P. pruinosus. P. pruinosus and C. murina were the most abundant isopods in the leaf litter, and the new species was third in abundance; Trichorhina donaldsoni was relatively rare. In matted, high grass vegetation near the leaf litter, no other isopod was found with the new taxon. The genus Philoscia is placed in the subfamily Philoscinae of the family Oniscidae by Vandel (1955). Philoscia bonita, n. sp. Description. Oblong-oval, about one-third as wide as long; long setae cover very prominent second antennae; very large uropods; abdomen abruptly narrower than thorax. Legs and eyes prominent; whole body covered with long setae. Second antennae about onethird to one-half length of animal; proximal segments about equal in length, together slightly longer than fourth segment. Fifth segment longest, being about length of second and third segments combined. Triarticulate flagellum slightly longer than fifth peduncular segment; first article slightly longer than either article two or three which are equal in length. Article three tipped by several sensorv setae. Head moderately large; eye compound, with 16 to 17 ocelli. Eyes stand out distinctly against dark background. Head smooth, without lateral lobes; slight indentation just above supra-antennal line. Triarticulate first antennae very small, hardly noticeable. Lateral borders of first thoracic tergite extended forward to partially enclose head. Posterior borders of second tergite slightly curved forward; posterior borders of third tergite at approximate right angles to anterior-posterior axis (see lateral view, Fig. 27). Lateral borders of tergite five to seven progressively more pointed; seven most pointed. Posterior lateral extensions of last tergite enclose first two abdominal segments. Lateral borders of all abdominal segments pointed; and visible in dorsal view. Uropods very prominent with large basal segments, with slight 1 Present address: Department of Zoology and Entomology, Montana State College, Bozeman, Montana.