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Species Armadillidium nasatum

Woodlouse - Armadillidium nasatum Orange woodlouse - Armadillidium nasatum WI061014 - 007 - Armadillidium nasatum Isopoda, Oniscus ocellus? - Armadillidium nasatum Armadillidium - Armadillidium nasatum insect underneath plant container outside - Armadillidium nasatum Youngsters - Armadillidium nasatum Pillbug - Armadillidium nasatum
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Crustacea (Crustaceans)
Class Malacostraca (Malacostracans)
Superorder Peracarida (Peracarida (Amphipods and Isopods))
Order Isopoda (Isopods)
Suborder Oniscidea (Woodlice)
Infraorder Holoverticata
No Taxon (Orthogonopoda)
No Taxon (Crinocheta)
Family Armadillidiidae (Pillbugs)
Genus Armadillidium
Species nasatum (Armadillidium nasatum)
Synonyms and other taxonomic changes
=mehelyi, nasutum, quadrifrons, sorrentinum, speyeri
Explanation of Names
Author of species is Budde-Lund 1885
To 21 mm
Body ovate, contractile into a ball; nearly twice as long as wide.
Head nearly three times as wide as long, with small, median V-shaped notch. Epistome triangular; broad basal part being anterior and projecting in front of head, giving head the appearance of having broad, quadrate median lobe. Eyes small, composite, situated in antero-lateral angles. A groove separates antero-lateral margin of head from antennal lobe, which is large, conspicuous, well-rounded. In this groove the antennae lie. First pair of antennae small and inconspicuous; second pair have first article short; second is twice as long as first; third is little shorter than second; fourth is equal in length to second; fifth is twice as long as fourth. Flagellum composed of two long, subequal articles. Second antennae extend to posterior margin of first thoracic segment.
First segment of thorax is little longer than any following segments, and has antero-lateral angles produced forward to surround the head, and post-lateral angles produced backward. Epimera not distinct in any of the segments.
First two segments of abdomen have lateral parts covered by seventh thoracic segment. The three following segments continue the oval outline of the body. Sixth (terminal) segment subtriangular, with sides a little concave and apex rounded. Basal segment or peduncle of uropoda not visible in dorsal view. It is large and somewhat quadrate. Outer branch occupies all space between lateral part of fifth abdominal segment and terminal abdominal segment. Outer branch is broad posteriorly and well rounded. Inner branch extends to extremity of outer branch and to extremity of abdomen.
(above text condensed from Discover Life site)
native to sw. Europe, adventive in the New World(1); in our area, e. NA (QC-MN-NE to NC-AR) and w. NA (ID-BC-CA)
Grasslands, quarries, gardens, greenhouses.
Life Cycle
They molt one half at a time
Internet References
Works Cited
1.Checklist of the terrestrial isopods of the New World (Crustacea, Isopoda, Oniscidea)
Leistikow A., Wägele J.W. 1999. Rev. Bras. Zool. 16: 1-72.