Paralysis tick
Ixodes holocyclus
Family: Ixodidae
Order: Ixodida
Superorder: Parisitiformes
Class Arachnida
The Australian paralysis tick is one of 75 species of tick in Australia. The Paralysis Tick can be confused with other species such as the Brown Dog Tick.
This photo shows the hypostome, the barbed mouthparts of the tick. At the end of the hypostome are the chelicerae or cutting parts for penetrating the skin of the host. The palps are sensory organs that assist in guiding the hypostome into position. They are shown spayed out in the picture but are normally held close to the hypostome when not feeding.
In this photo, we can see the front pair of legs and the rear pair are darker than the others. This is a distinguishing feature of Ixodes holocyclus as is the shape of the palps and the lack of festoons (around the rear margin of the back half of the tick’s body). The hypostome is barbed which is also a feature found in I. holocyclus. The anal groove forming a line anterior to the anus is a characteristic of Ixodes spp.
This species is the most medically significant of the Australian Ticks and can inject toxins into its host. According to the NSW Health authority, early symptoms in humans include “rashes, headache, fever, flu like symptoms, tenderness of lymph nodes, unsteady gait, intolerance to bright light, increased weakness of the limbs and partial facial paralysis”. Symptoms can increase as the tick feeds.
The species is known as a vector of several pathogens including Tick Typhus and potentially bacteria which may be responsible for symptoms that resemble Lyme's disease. The Australian government does not support a diagnosis of Lymes disease originating in Australia, as the causing Bacterium species, Borrelia burgdorferi , is not present in Australia. However, it is without doubt that Lymes-like symptoms are known in Australia and it is likely that ticks in Australia are vectors for a bacterial species related to Borrelia burgdorferi .
Tick expert Ken Kwok had this to say in response to a query about the role of 'festoons' in identification:
"See the first couplet in a visual key to the Aussie paralysis ticks I published some years back (Kwak 2017). The festoons are a feature of the non-Ixodes hard ticks (Metastriata). They are a series of grooves along the posterior edge of the idiosoma which can be very obvious in unfed adults but become far more challenging to see in fed adults and in immature stages."
Ken's key will be incorporated in the comment below if he gives permission for me to do so.
DSC08741_DSC08803 tight crop of proboscis
Paralysis tick
Ixodes holocyclus
Family: Ixodidae
Order: Ixodida
Superorder: Parisitiformes
Class Arachnida
The Australian paralysis tick is one of 75 species of tick in Australia. The Paralysis Tick can be confused with other species such as the Brown Dog Tick.
This photo shows the hypostome, the barbed mouthparts of the tick. At the end of the hypostome are the chelicerae or cutting parts for penetrating the skin of the host. The palps are sensory organs that assist in guiding the hypostome into position. They are shown spayed out in the picture but are normally held close to the hypostome when not feeding.
In this photo, we can see the front pair of legs and the rear pair are darker than the others. This is a distinguishing feature of Ixodes holocyclus as is the shape of the palps and the lack of festoons (around the rear margin of the back half of the tick’s body). The hypostome is barbed which is also a feature found in I. holocyclus. The anal groove forming a line anterior to the anus is a characteristic of Ixodes spp.
This species is the most medically significant of the Australian Ticks and can inject toxins into its host. According to the NSW Health authority, early symptoms in humans include “rashes, headache, fever, flu like symptoms, tenderness of lymph nodes, unsteady gait, intolerance to bright light, increased weakness of the limbs and partial facial paralysis”. Symptoms can increase as the tick feeds.
The species is known as a vector of several pathogens including Tick Typhus and potentially bacteria which may be responsible for symptoms that resemble Lyme's disease. The Australian government does not support a diagnosis of Lymes disease originating in Australia, as the causing Bacterium species, Borrelia burgdorferi , is not present in Australia. However, it is without doubt that Lymes-like symptoms are known in Australia and it is likely that ticks in Australia are vectors for a bacterial species related to Borrelia burgdorferi .
Tick expert Ken Kwok had this to say in response to a query about the role of 'festoons' in identification:
"See the first couplet in a visual key to the Aussie paralysis ticks I published some years back (Kwak 2017). The festoons are a feature of the non-Ixodes hard ticks (Metastriata). They are a series of grooves along the posterior edge of the idiosoma which can be very obvious in unfed adults but become far more challenging to see in fed adults and in immature stages."
Ken's key will be incorporated in the comment below if he gives permission for me to do so.
DSC08741_DSC08803 tight crop of proboscis