|
abdomen |
(see
opisthosoma) |
|
aculeus |
the
curved stinger arising distally from the telson
vesicle. The aculeus is hollow and bears a small
distal opening to allow venom from the internal
venom glands of the vesicle to be injected for
predation or defense. |
|
basal pectinal piece |
a
rectangular plate on the underside of mesosomal
segment II to which the pectines attach. |
|
basitarsus |
the
proximal portion of the tarsus, located between the
tibia and telotarsus. |
|
book lungs |
the
internal respiratory structures of scorpions.
|
|
carapace |
the
dorsal plate of the cephalothorax, bearing the
lateral and median eyes. |
|
carinae |
cuticular ridges on body surfaces, often associated
with attachment of internal musculature. The
strength and granulation of carinae are of
considerable taxonomic importance. |
|
cephalothorax |
(see
prosoma) |
|
chela |
the
pincer of the pedipalp, comprising the chela palm
and the fixed and movable fingers. |
|
chelicerae |
the
anteriormost set of appendages in the scorpion,
comprising the mouthparts. The chelicerae of
scorpions are chelate and |
|
chitin |
a
structural polysaccharide that makes up the bulk of
the scorpion cuticle. Added to chitin are a variety
of other substances, such as proteins (sclerotized
and unsclerotized) and waxes which give special
properties to the cuticle. |
|
coxa |
the
proximal segment of the appendage (chelicera,
pedipalp, leg) which joins the appendage to the
body. The coxae in modern scorpions, together with
the sternum, make up the coxosternal region on the
underside of the cephalothorax. |
|
cuticle |
the
nonliving portion of the scorpion's integument,
secreted by the underlying epidermis. The cuticle
is a distinctly layered structure made of chitin,
waxes, sclerotized and unsclerotized proteins, and
other materials. |
|
dactyl |
the
median claw at the ventrodistal tip of the
telotarsus of the leg. The dactyl is smaller than
the ungues (tarsal claws). |
|
dentate margin |
(see
primary denticle row). |
|
enlarged primary row denticle |
a
larger denticle found at the proximal end of a
primary denticle subrow; the enlarged primary row
denticles are situated within the denticle row and
serve to divide the denticle row into distinct
subrows. |
|
femur |
the
third leg or pedipalpal segment from the base. The
femur is the first long segment. On the pedipalp,
the femur bears trichobothria, setae, and carinae of
taxonomic importance. |
|
fixed finger |
the
immovable digit of the chelicera or pedipalp chela.
The cheliceral fixed finger bears a basal bicusp, a
subdistal tooth, and a distal tooth; on its
underside is a weak to moderate longitudinal carina
which may bear denticles or crenulations. The fixed
finger of the pedipalp chela bears trichobothria and
a variety of setae; in addition it bears the primary
denticle row, which forms its cutting edge (or
dentate margin) with the movable finger. |
|
genital opercula |
a
pair of small flaps that cover the genital pore, the
two together forming an oval structure. |
|
genital papillae |
small fingerlike projections that are associated
with the membrane of the genital pore of the male
scorpion and protrude from beneath the distal
margins of the genital opercula. |
|
genital pore |
the
genital opening concealed by the genital opercula. |
|
hemispermatophore |
one
of a pair of formative internal male reproductive
structures, secreted by the paraxial organ. During
courtship, the two hemispermatophores are cemented
together to form the spermatophore, which carries a
sperm packet and is deposited on the substrate. |
|
inner accessory denticles |
denticles flanking the primary denticle row of the
chela fingers, usually more or less paired with an
enlarged primary row denticle. |
|
interocular triangle |
the
area on the carapacial surface lying between the
median and lateral eyes. |
|
intersegmental membrane |
soft
cuticle between adjacent tergites or sternites on
the mesosoma. |
|
keels |
(see
carinae). |
|
lateral eyes |
the
paired cluster of small eyes at the anterolateral
corners of the carapace. In vaejovids, there are
typically three pairs of lateral eyes, although
aberrations and exceptions exist (for example, the
troglophilic Uroctonites sequoia often bears
two pair of lateral eyes instead of three). |
|
manus |
the
palm of the chelicera or of the pedipalp chela. Attached
distally to the palm are the fixed and movable
fingers of these two chelate appendages. |
|
median claw |
(see
dactyl). |
|
median eyes |
the
pair of larger eyes situated middorsally on the
carapace. |
|
mesosoma |
the
"body" of the scorpion, comprising the first seven
of the opisthosomal (abdominal) segments. A given
mesosomal segment is provided dorsally with a
tergite and ventrally with the genital opercula (1st
mesosomal segment), pectines (2nd
mesosomal segment), or sternite (segments III-VII).
The tergites and sternites are joined together by
softer cuticle called intersegmental membranes; the
tergites and sternites are connected by similar soft
cuticle referred to as the pleural membrane. |
|
metasoma |
the
"tail" of athe scorpion, consisting of five tubular
segments. The metasoma is actually part of the
opisthosoma (abdomen), rather than an actual tail.
The metasomal segments bear longitudinal carinae,
whose strength and granulation provide useful
taxonomic characters. Ventrodistally, in a
membranous area, on the fifth metasomal segment is
the anus. |
|
movable finger |
the
movable digit of the chelicera or of the pedipalp chela.
On the chelicera, the movable finger bears a dorsal
series of teeth and a ventral carina (the ventral
carina may bear crenulations or denticles);
ventrodistally on the movable finger may be a
serrated comb-like structure called the serrula. On
the pedipalp, the movable finger (considered to be
the tarsus of the pedipalp) bears a series of
denticles along its cutting margin, as for the fixed
finger. The movable fingers attach to their
respective appendages by an articular membrane. |
|
opisthosoma |
the
abdomen of the scorpion, consisting of seven
mesosomal and five metasomal segments. The
opisthosoma also bears the genital pore and opercula
(1st segment), the pectines (2nd
segment), and four pairs of book lung openings on
the sternites. |
|
ovariuterus |
a
reticulate internal network of reproductive tubules
in the female scorpion. In vaejovids, the oocytes
develop in association with the ovariuterus and move
to the interior for fertilization and embryonic
development. |
|
palm |
the
thickened basal portion of the pedipalp chela from
which the fixed finger arises and the movable finger
articulates. The palm bears a number of carinae
(keels), whose strength and granulation provide good
taxonomic characters. |
|
patella |
on
the pedipalp, the second long segment from the base. |
|
pectines |
large, comblike sensory structures found ventrally
on the second mesosomal segment. The pecten is a
soft, flexible structure made of the following
components: an anterior series of marginal lamella,
a series of median lamella, a series of small
circular fulcra, and a series of elongated pectinal
teeth oriented at right angles to the marginal and
median lamellae. The pectinal teeth bear sensorial
areas whose senilla provide for both
mechanoreception (evaluation substrates) and
chemoreception (pheromone detection). The pectinal
tooth count is of taxonomic importance. |
|
pedal spurs |
two
small spur-like structures situated in the
ventrodistal articular membrane of the leg between
the basitarsus and telotarsus. |
|
pedipalps |
the
second pair of appendages on the scorpions prosoma,
consisting of the coxa, trochanter, femur, patella,
chela manus, fixed finger, and movable finger (the
chela manus and fixed finger are considered the
tibia, and the movable finger the tarsus). |
|
pleural membrane |
soft
cuticle on the lateral aspects of the mesosoma
between the tergites and sternites. |
|
pre-oral chamber |
a
small chamber anterior to the mouth surrounded
ventrally by the coxal endites (of legs I and II),
laterally by the pedipalpal coxae, and dorsally by
the chelicerae. As a prey item is masticated by the
chelicerae, digestive enzymes are regurgitated into
the chamber to begin digestion of the food. The
walls of the pre-oral chamber are supplied with a
dense array of fine setae that serve as a filter to
keep larger particles from entering the mouth. |
|
primary denticle row |
the
row of denticles found on the cutting margins of the
pedipalp |
|
prosoma |
the
anterior of the two main body regions of a scorpion,
serving as a combined head and thorax. The prosoma
bears the carapace dorsally and the coxosternal
region ventrally; the chelicerae, pedipalps, and
four pairs of legs are associated with the prosoma. |
|
scalloping |
in reference to
the lateral aspect of the pedipalp chela fingers,
when the margins of one or more of the denticle rows
are concave (rather than straight). Scalloping of
the basal denticle row of the fixed finger often
corresponds to the development of a lobe on the
movable finger. |
|
serrula |
a
cuticular comb-like structure found ventrodistally
on the cheliceral movable finger of many vaejovids. |
|
seta |
a
socketed, chitinous hair or bristle found on the
body and appendages of scorpions. Setae vary
considerably in thickness, shape, and length. Most
are innervated and serve as tactile receptors or
chemoreceptors. |
|
setal comb |
a
linear array of bristles associated with the
basitarsus (and sometimes the telotarsus) of the
legs, in particular legs I-III. Setal combs are
characteristic of psammophilic (sand dwelling)
scorpions; among the vaejovids, setal combs are well
developed in Paruroctonus (most species),
Paravaejovis, Smeringurus, and
Vejovoidus. A few species of Vaejovis
have setal combs, but development is not as great as
in the paruroctines. |
|
spermatophore |
the
male reproductive structure, formed during courtship
from two internal hemispermatophores (see
hemispermatophore for more information). |
|
spinules |
smaller, spine-like projections of the cuticle (not
socketed setae) which are located on the basitarsi
and tarsi of the legs. |
|
spiracles |
the
external openings, located on the ventrolateral
corners of sternites III-VI, into the book lungs of
the scorpion. |
|
sternites |
ventral plates associated with the mesosoma. |
|
sternum |
a
small median plate on the underside of the prosoma
lying between the coxae of the legs. In vaejovids,
the sternum is always pentagonally shaped. |
|
subaculear tubercle (or tooth) |
a
cuticular prominence located on the ventrodistal
portion of the vesicle, where the aculeus joins. |
|
tarsal claws |
(see
ungues). |
|
tarsus |
the
distalmost segment of the leg, including the
basitarsus and telotarsus. Also, the movable finger
of the pedipalp. |
|
telotarsus |
the
distal portion of the tarsus, to which are attached
the ungues (tarsal claws) and dactyl. |
|
telson |
the
stinger apparatus of the scorpion, consisting of a
bulb-shaped vesicle and curved aculeus. |
|
tergite |
dorsal plates associated with the mesosoma. |
|
tibia |
the
fourth segment of the leg from the base. Also, the
chela manus + fixed finger of the pedipalp. |
|
trichobothrium |
a
thin, willowy sensory seta arising from a (usually)
large, circular socket on the surface of the
pedipalpal cuticle. The trichobothrium is a highly
sensitive hair that is easily moved by air-borne
vibrations, allowing it to be used to detect aerial
prey, such as moths. Trichobothria are located only
on the pedipalpal femur, patella, and tibia (chela
palm + fixed finger). |
|
trochanter |
the
second segment of the pedipalp or leg. On the leg,
the trochanter is a short cylindrical segment. |
|
ungues |
the
curved, paired claws located at the distal end of
the telotarsus. Ventrally, between the two claws is
the smaller, triangular dactyl. |
|
vesicle |
the
bulb-shaped portion of the telson which gives rise
distally to the aculeus. Internally, the vesicle
contains the paired venom glands that are surrounded
my musculature to squeeze the venom into the aculear
duct. |