Ticks of Domestic Animals in Africa - Alan R Walker - Science Writer

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Mesial to Palp
Mesial area of enamel on conscutum: in male Amblyomma the pattern
of enamel on the conscutum usually includes a mesial patch in the
central anterior region. This may be short, or elongate.
Mesial areas of enamel on scutum: in female Amblyomma an area of
enamel colour in the lower centre of the scutum varies from small and
rounded, to large and elongate.
Mesial area: the central anterior part of the scutum or conscutum of
Amblyomma species. In other genera this area may be called the central
field.
Monotropic: where the immature stages of a tick feed only on the
same type of host, such as ruminants, as the adult ticks.
Mouthparts: consist of the paired palps, the blade shaped hypostome
and the paired chelicerae within a sheath. In argasid ticks the mouthparts
are situated on the ventral surface of the adults. In ixodid ticks the
mouthparts project from the anterior margin of the adult tick.
Myiasis: a disease caused by the infestation of flesh of mammals by
larvae of flies; the infestation may start at wounds caused by ticks.
Nidicolous: living in the nest of the host, see Endophilic.
Orbit: a circular groove surrounding the eye of some ticks, very typical
of Hyalomma species.
Ornamentation: having a pattern of coloured pigment in the integument
of the scutum; this colouration is known as enamel. The term
enamel is used in this guide but the terms ornamentation or ornate in
other guides and keys mean the same.
Palaearctic zoogeographical region: an area characterised by groups
of related animals which includes all of Europe and central Asia and
extends into Africa north of the central Sahara. Africa south of the
Sahara is in the Afrotropical region. Central and South America are in
the Neotropical region.
Palps: paired structures of the mouthparts. They are moveable and
spread away from the penetrating hypostome and chelicerae to remain
outside the skin when the tick is feeding. They consist of four parts like
segments, known as articles. Article 4 is very small and has a sensory
function used in feeding. The illustration shows the position of palpal
articles 1 to 4 on the ventral surface of Rhipicephalus (Boophilus).
4
2
Palpal article 1 internal margin: in Rhipicephalus (Boophilus) females
and males the first article of the palps has a characteristic structure
of the internal margin, facing the hypostome. There is either no
protuberance, long and slightly concave profile. Or there is no protuberance,
short and distinctly concave profile. Or there is a protuberance
with pectinate setae (one or two setae on each protuberance,
pectinate means split like a comb).
Palp articles 2 dorsal spur: in female and male Haemaphysalis there
may be a backward pointing spur in the form of an angular projection
from the posterior margin of the dorsal surface of the second article of
the palps. This is either absent, or present.
3
1