Introduction - Pests of Ornamental Trees, Shrubs and Flowers - page 8

elongate, worm-like mites with a pair of setae on
the prodorsal shield; hysterosoma subdivided into
numerous tergites and sternites, typically subequal
anteriorly: genera Acalitus, Aceria, Artacris,
Eriophyes . Subfamily Phyllocoptinae - cigar-
shaped to pear-shaped mites with a pair of setae
on the prodorsal shield; hysterosoma subdivided
by relatively few, broad tergites and several narrow
sternites: genera Acaricalus, Aculus, Epitrimerus,
Phyllocoptes, Tegonotus, Vasates .

Superfamily Tetranychoidea: spider-like mites with
long, needle-like chelicerae: family Tetranychidae
(p. 426); family Tenuipalpidae (p. 432).

Superfamily Eupodoidea: includes tarsonemid-like
species with claws on each pair of tarsi: family
Siteroptidae (p. 432).

Astigmata: soft-bodied, semitransparent mites;
chelicerae forceps-like.

Superfamily Tarsonemoidea: mites with short,
needle-like mouthparts: family Tarsonemidae
(p. 423).

Superfamily Acaroidea: features as for order:
family Acaridae (p. 433).

Woodlice

Woodlice (phylum Arthropoda: class Crustacea) are
terrestrial, 14-legged crustaceans, forming a distinct
order, the Isopoda. They feed on decaying vegetation,
but also sometimes attack the roots, stems and leaves of

healthy plants; animal matter is also included in the diet,
individuals commonly feeding on dried-blood fertilizer:
family

Armadillidiidae (p. 434); family Oniscidae

(p. 435); family Porcellionidae (p. 435).

Millepedes

Millepedes (phylum Arthropoda: class Diploda) usually
have elongate bodies composed of a variable number of
double abdominal segments, most of which bear two
pairs of legs. The head is armed with biting mouthparts,
and bears simple eyes and a pair of short, clubbed
antennae. Millepedes are secretive, light-shy creatures,

and usually inhabit moist, sheltered situations. Although
some species are scavengers, and a few are
phytophagous or predacious, most feed on decaying
vegetation. Millepedes sometimes damage germinating
seeds and seedlings, but are of little or no importance on
older plants.

Symphylids

Symphylids (phylum Arthropoda: class Symphyla) are
small, soft-bodied creatures with three pairs of
mouthparts, 12 pairs of legs and a posterior pair of cerci.

Most species inhabit the soil and feed on decaying
vegetation; a few attack the underground parts of
plants.

Nematodes

Nematodes (phylum Nematoda) are unsegmented
worm-like invertebrates that lack circulatory and
respiratory systems, and are devoid of cilia (both
external and internal); also, they possess a stiff yet
flexible external cuticle which, unlike that of insects,

lacks chitin. Nematodes are often abundant in soils,
feeding on various micro-organisms, but many species
are parasitic. Those attacking vertebrates (including
man) are commonly known as 'roundworms', whereas
those associated with plants are often known as