Parasitiform

This photograph depicts a dorsal view of an engorged female "lone star tick", Amblyomma americanum. Note a number of round, amber-colored eggs showing from beneath the head region, which were just laid by this female. An engorged female of this species can lay approximately 2000-2500 eggs. To view additional images related to this tick specie, see PHIL 4407, 8676, 8677, 8678, and 8680 through 8685.Created: 2006

This photograph depicts a dorsal view of an engorged female lone star tick, Amblyomma americanum. An ixodid or hard tick, A. americanum is found through the eastern and south-central states and can transmit disease agents that affect humans, dogs, goats, and white-tailed deer. Representatives from all three of its life stages aggressively bite people in the southern U.S. Lone star ticks transmit Ehrlichia chaffeensis and Ehrlichia ewingii, both of which cause disease. Borrelia lonestari, a pathogen associated with Southern tick-associated associated rash illness (STARI), also infects lone star ticks. Research suggests that up to 10% of the lone star ticks in an endemic area can be infected with any one of these pathogens. These ticks also are infected with a spotted-fever group Rickettsia, Rickettsia amblyommii but it is unknown at this time if this bacterium causes disease.Created: 2006

This photograph depicts a dorsal view of a female lone star tick, Amblyomma americanum. An ixodid or hard tick, A. americanum is found through the eastern and south-central states and can transmit disease agents that affect humans, dogs, goats, and white-tailed deer. Representatives from all three of its life stages aggressively bite people in the southern U.S. Lone star ticks transmit Ehrlichia chaffeensis and Ehrlichia ewingii, both of which cause disease. Borrelia lonestari, a pathogen associated with Southern tick-associated associated rash illness (STARI), also infects lone star ticks. Research suggests that up to 10% of the lone star ticks in an endemic area can be infected with any one of these pathogens. These ticks also are infected with a spotted-fever group Rickettsia, Rickettsia amblyommii but it is unknown at this time if this bacterium causes disease.Created: 2006

This illustration depicts two Argasidae soft ticks from a lateral view; one with, and one without a definite suture line.Created: 1976

This illustration depicts the location of a tick’s breathing orifices, each contained in a hard chitinous spiracular plate.Created: 1976

This drawing shows the morphologic differences between soft ticks, Argasidae, and hard ticks, Ixodidae.Created: 1976

This drawing depicts some of the anatomic characteristics displayed by ticks that are members of the genus Amblyomma.Created: 1976

This illustration shows the growth stages of the American dog tick, Dermacentor variabilis, from eggs to adult insects.Created: 1975

This photograph depicts a dorsal view of a male Rocky Mountain wood tick, Dermacentor andersoni. This tick specie is a known North American vector of Rickettsia rickettsii, which is the etiologic agent of Rocky Mountain spotted fever.Rocky Mountain spotted fever, like all rickettsial infections, is classified as a zoonosis. Zoonoses are diseases of animals that can be transmitted to humans. Many zoonotic diseases require a biological vector (e.g., a mosquito, tick, flea, or mite) in order to be transmitted from the animal host to the human host. In the case of Rocky Mountain spotted fever, ticks are the natural hosts, serving as both reservoirs and vectors of R. rickettsii. Ticks transmit the organism to vertebrates primarily by their bite. Less commonly, infections may occur following exposure to crushed tick tissues, fluids, or tick feces.See PHIL 10869, for a side-by-side comparative view of both a male and female D. andersoni tick.Created: 2008

This 2005 image depicted a male brown dog tick, Rhipicephalus sanguineus from a superior, or dorsal view looking down on this hard tick’s scutum, or keratinized shield which entirely covers its back, identifying it as a male. In the female, the dorsal abdomen is only partially covered, thereby, offering room for abdominal expansion when she becomes engorged with blood while ingesting her blood meal obtained from her host.Though not the primary vector for Rocky Mountain spotted fever (RMSF) like the American dog tick, Dermacentor variabilis, and the Rocky Mountain wood tick D. andersoni, R. sanguineus has been found to be a less-common vector as well. This tick is distributed throughout the world. It also is known to transmit diseases to animals including canine babesiosis, bovine anaplasmosis, East Coast fever and Texas cattle fever. It can also spread tularemia, and tick-borne typhus to human beings.Created: 2005

This photograph depicted a dorsal view of a monitor lizard tick, Amblyomma exornatum, formerly known as Aponomma exornatum. Native to Africa, this is a reptilian tick, and as the name suggests, is mainly a parasite of monitor lizards. The four pairs of jointed legs, places these ticks in the Phylum Arthropoda, and the Class Arachnida.Created: 2006

This photograph depicted a dorsal view of a monitor lizard tick, Amblyomma exornatum, formerly known as Aponomma exornatum. Native to Africa, this is a reptilian tick, and as the name suggests, is mainly a parasite of monitor lizards. The four pairs of jointed legs, places these ticks in the Phylum Arthropoda, and the Class Arachnida.Created: 2006

This photograph depicted a dorsal view of a monitor lizard tick, Amblyomma exornatum, formerly known as Aponomma exornatum. Native to Africa, this is a reptilian tick, and as the name suggests, is mainly a parasite of monitor lizards. The four pairs of jointed legs, places these ticks in the Phylum Arthropoda, and the Class Arachnida.Created: 2006

This photograph depicted a dorsal view of a monitor lizard tick, Amblyomma exornatum, formerly known as Aponomma exornatum. Native to Africa, this is a reptilian tick, and as the name suggests, is mainly a parasite of monitor lizards. The four pairs of jointed legs, places these ticks in the Phylum Arthropoda, and the Class Arachnida.Created: 2006