Amblyomma, also known as the Bont Ticks, are a genus of hard ticks. Some are disease vectors, such as of Rocky Mountain spotted fever in United States or ehrlichiosis in Brazil.

This genus is the third largest in the family Ixodidae, after Ixodes and Haemaphysalis, with its species primarily occupying the torrid zones of all the continents. The centre of species diversity is on the American continent, where half of all the species occur. On this continent, Amblyomma species reach far beyond the torrid zone, up to the 40th parallel in the Northern Hemisphere, to the 50th parallel in the Southern Hemisphere, and even reaches the alpine zone of the Andes. They also occur in Eurasia, Africa and Australia.

Evolutionary history and systematics Amblyomma is the largest genus in the Amblyocephalus lineage, and the only member of the Amblyomminae subfamily. Modelling suggests the most recent common ancestor (MRCA) of the Amblyocephalus originated approximately 48 million years ago, and the genus began to diversify approximately 37 ma. The Amblyomma MRCA likely evolved in a region between South America and Antarctica, lending credence to an out-of-Antarctica hypothesis for the genus' origin. A genetic divide in modern lineages between Australian Amblyomma and Amblyomma from the rest of the world supports the idea that the genus diverged in two directions out of Antarctica, with one lineage dispersing into Australian Gondwana, and another into South American Gondwana, at the end of the Eocene.

The genus has historically been large, and highly varied, morphologically, making circumscription criteria in accordance with genetic phylogenies difficult to define. Following the 2020 and 2024 excision of Africaniella and Cryptocroton species, respectively, Amblyomma is now monophyletic. Many species complexes remain unresolved, however. Additionally, most Amblyomma subgenera remain polyphyletic (Cernyomma, Anastosiella, Haemalastor, Xiphiastor, Adenopleura, Aponomma, and Dermiomma), with only Amblyomma (Amblyomma) and Amblyomma (Walkeriana) being monophyletic.Nava, S., Guglielmone, A.A., Mangold, A.J. An overview of systematics and evolution of ticks. Front Biosci. 2009;14:2857–77.

Description Amblyomma species are medium to large, often ornamented ticks. They are subcircular to elliptical, with subpentagonal basis capituli and elongate mouthparts. Most species have eyes, except for those of the subgenus Amblyomma (Aponomma). Lateral grooves and festoons are usually distinct. Amblyomma ticks parasitise a wide range of vertebrates, except for amphibians.

The internal anatomy of Amblyomma species has been described in detail in a few species, including Amblyomma maculatum and Amblyomma variegatum.

Species

Amblyomma albolimbatum Neumann, 1907 Amblyomma albopictum Neumann 1899 Amblyomma americanum Linnaeus, 1758 – lone star tick Amblyomma anicornuta Apanaskevich & Apanaskevich, 2018 Amblyomma antillorum Kohls 1969 Amblyomma arcanum Karsch, 1879 Amblyomma argentinae Neumann, 1905 Amblyomma astrion Dönitz, 1909 Amblyomma aureolatum Pallas, 1772 Amblyomma auricularium Conil, 1878 Amblyomma australiense Neumann, 1905 Amblyomma babirussae Schulze, 1933 Amblyomma beaurepairei Vogelsang & Santos Dias 1953 Amblyomma boeroi Nava et al., 2009 Amblyomma boulengeri Hirst & Hirst, 1910 Amblyomma brasiliense Aragão, 1908 Amblyomma breviscutatum Neumann, 1899 Amblyomma cajennense Fabricius, 1787 Amblyomma calabyi Roberts, 1963 Amblyomma calcaratum Neumann, 1899 Amblyomma chabaudi Rageau, 1964 Amblyomma clypeolatum Neumann, 1899 Amblyomma coelebs Neumann, 1899 Amblyomma cohaerens Dönitz, 1909 Amblyomma compressum Macalister, 1872 Amblyomma cordiferum Neumann, 1899 Amblyomma crassipes Neumann, 1901 Amblyomma crassum Robinson, 1926 Amblyomma crenatum Neumann 1899 Amblyomma cruciferum Neumann, 1901 Amblyomma darwini Hirst & Hirst, 1910 Amblyomma dissimile Koch 1844 Amblyomma dubitatum Neumann 1899 Amblyomma eburneum Gerstäcker, 1873 Amblyomma echidnae Roberts 1953 Amblyomma exornatum Koch, 1844 Amblyomma extraoculatum Neumann 1899 Amblyomma falsomarmoreum Tonelli-Rondelli, 1935 Amblyomma fimbriatum Koch, 1844 Amblyomma flavomaculatum Lucas, 1846 Amblyomma fulvum Neumann, 1899 Amblyomma fuscolineatum Lucas, 1847 Amblyomma fuscum Neumann, 1907 Amblyomma geayi Neumann, 1899 Amblyomma gemma Dönitz, 1909 Amblyomma geochelone Durden, Keirans & Smith, 2002 Amblyomma geoemydae Cantor, 1847 Amblyomma gervaisi Lucas, 1847 Amblyomma glauerti Keirans, King & Sharrad, 1994 Amblyomma goeldii Neumann 1899 Amblyomma hadanii Nava et al., 2014 Amblyomma hainanense Teng, 1981 Amblyomma hebraeum Koch, 1844 Amblyomma helvolum Koch, 1844 Amblyomma hirtum Neumann, 1906 Amblyomma humerale Koch, 1844 Amblyomma incisum Neumann, 1906 Amblyomma inopinatum Santos Dias, 1989 Amblyomma inornatum Banks, 1909 Amblyomma integrum Karsch, 1879 Amblyomma interandinum Nava et al., 2014 Amblyomma javanense Supino, 1897 Amblyomma kappa Kwak, 2024 Amblyomma komodoense Oudemans, 1928 Amblyomma kraneveldi Anastos, 1956 Amblyomma latepunctatum Tonelli Rondelli, 1939 Amblyomma latum Koch, 1844 Amblyomma lepidum Dönitz, 1909 Amblyomma limbatum Neumann, 1899 Amblyomma loculosum Neumann, 1907 Amblyomma longirostre Koch, 1844 Amblyomma macfarlandi Keirans, Hoogstraal & Clifford, 1973 Amblyomma macropi Roberts, 1953 Amblyomma maculatum Koch, 1844 Amblyomma marmoreum Koch, 1844 Amblyomma mixtum Koch, 1844 Amblyomma moreliae Koch, 1867 Amblyomma moyi Roberts, 1953 Amblyomma multipunctum Neumann, 1899 Amblyomma naponense Packard, 1869 Amblyomma neumanni Ribaga 1902 Amblyomma nitidum Hirst & Hirst, 1910 Amblyomma nodosum Neumann, 1899 Amblyomma nuttalli Dönitz, 1909 Amblyomma oblongoguttatum Koch, 1844 Amblyomma ovale Koch, 1844 Amblyomma pacae Aragão, 1911 Amblyomma parkeri Fonseca & Aragao, 1952 Amblyomma parvitarsum Neumann, 1901 Amblyomma parvum Aragão, 1908 Amblyomma patinoi Nava, et al., 2014 Amblyomma pattoni Neumann, 1910 Amblyomma paulopunctatum Neumann 1899 Amblyomma pecarium Dunn, 1933 Amblyomma personatum Neumann, 1901 Amblyomma pictum Neumann, 1906 Amblyomma pilosum Neumann, 1899 Amblyomma pomposum Dönitz, 1909 Amblyomma postoculatum Neumann, 1899 Amblyomma pseudoconcolor Aragão, 1908 Amblyomma pseudoparvum Guglielmone, Mangold & Keirans, 1990 Amblyomma quadricavum Schulze, 1941 Amblyomma rhinocerotis de Geer, 1778 Amblyomma robinsoni Warburton 1927 Amblyomma romarioi Martins, Luz and Labruna, 2019 Amblyomma romitii Tonelli Rondelli, 1939 Amblyomma rotundatum Koch 1844 Amblyomma sabanerae Stoll, 1894 Amblyomma scalpturatum Neumann, 1906 Amblyomma sculptum Berlese, 1888 Amblyomma scutatum Neumann, 1899 Amblyomma soembawense Anastos, 1956 Amblyomma sparsum Neumann, 1899 Amblyomma splendidum Giebel, 1877 Amblyomma squamosum Kohls, 1953 Amblyomma supinoi Neumann, 1905 Amblyomma sylvaticum de Geer, 1778 Amblyomma tapirellum Dunn, 1933 Amblyomma tenellum Koch, 1844 Amblyomma testudinarium Koch, 1844 Amblyomma tholloni Neumann, 1899 Amblyomma tigrinum Koch 1844 Amblyomma tonelliae Nava et al., 2014 Amblyomma torrei Pérez Vigueras, 1934 Amblyomma triguttatum Koch 1844 Amblyomma trimaculatum Lucas, 1878 Amblyomma triste Koch 1844 Amblyomma tuberculatum Marx, 1894 Amblyomma usingeri Keirans, Hoogstraal & Clifford, 1973 Amblyomma varanense Supino, 1897 Amblyomma variegatum Fabricius 1798 Amblyomma varium Koch, 1844 Amblyomma vikirri Keirans, Bull & Duffield, 1996 Amblyomma williamsi Banks, 1924 Amblyomma yucumense Krawczak, Martins & Labruna, 2015

Fossil species

†Amblyomma birmitum Chitimia-Dobler et al., 2017 Burmese amber, Myanmar, Cenomanian. †Amblyomma near testudinis Lane & Poinar, 1986 Dominican amber, Dominican Republic, Miocene.

References