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Mites, Ticks, and Paleoparasitology

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ROCHA, G.C., and SERRA-FREIRE, N.M. Mites, Ticks, and Paleoparasitology. In: FERREIRA,
L.F., REINHARD, K.J., and ARAÚJO, A., ed. Foundations of Paleoparasitology [online]. Rio de
Janeiro: Editora FIOCRUZ, 2014, pp. 171-186. ISBN: 978-85-7541-598-6. Available from: doi:
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Part II - Parasite Remains Preserved in Various Materials and
Techniques in Microscopy and Molecular Diagnosis
11. Mites, Ticks, and Paleoparasitology
Gino Chaves da Rocha
Nicolau Maués da Serra-Freire
Mites, Ticks, and Paleoparasitology
171
Mites, Ticks, and Paleoparasitology
Gino Chaves da Rocha Nicolau Maués da Serra-Freire
11
The reconstitution of Earth’s evolutionary history, of living and extinct beings, fundamentally involves three fields
of study: geology, paleontology, and biology. In the late 20th century, biochemical and molecular techniques were
increasingly applied to studies in evolutionary genetics, phylogenetic analyses, and molecular systematics (Navajas &
Fenton, 2000). The study of geological layers, fossil records, and morphological and genetic characteristics to identify
relations between organisms produces valuable knowledge on the history and diversity of planetary life or planetary
biology, as suggested by Benner et al (2002).
Since the dawn of life on Earth, between 4.4 and 3.8 billion years ago (Chang, 1999), the various levels of
competition for ecotopes (spatial niches) and the struggle for the establishment of trophic niches (food resources) have
woven a complex web of biochemical relations among organisms (Forattini, 2004). The life and survival of species
result from constant adaptation to the challenges raised by favorable or unfavorable conditions in the environment.
In this long history of irradiation and evolutionary adaptation, microorganisms, plants, and animals have
developed mechanisms for absorbing and transferring energy (Chart 1) and “adopting” other organisms through
an association of interspecific energy and biochemical dependence. Conceptually, parasitism thus exists when an
organism finds its ecological niche in another life form. Parasitism is considered an ecological phenomenon (Zelmer,
1998; Rey, 2001; Ferreira, Reinhard & Araújo, 2008). Araújo et al. (2003) and Ferreira & Araújo (2005) present the
arguments and foundations for host-parasite-environment relations, stating that “parasitism is inherent to life”.
The use of available energy in the troposphere became a condition for the survival of living species, including
parasites and decomposers, with a key role in ecosystems.
Foundations of Paleoparasitology
172
Chart 1 – The energy cycle of living organisms on Earth: the energy pyramid in the modern age
Source and use of
energy
Energy released
(Kcal/m3)
Used for
respiration
(Kcal/m3)
Used for growth
(Kcal/m3)
% used for
growth/released
Unused
(Kcal/m3)
Transferred
(Kcal/m3)
% transferred/
total released
Produced by sun 1,700,000 100
Not absorbed by Earth 1,209,000 880,000
(68.22%) 410,00 24.118
Photosynthesis 410,000 389,190 20,810 5.08 12,977
(62.36%) 8,833 0.520
Plant respiration 20,810 11,997 8,833 42.45 5,463
(61.85%) 3,370 0.198
Herbivorous animals 3,370 1,890 1,480 43.92 1,500
(79.37%) 390 0.023
Carnivorous animals 390 316 74 18.97 53
(71.62%) 21 0/001
Omnivorous animals 21 13 8 38.10 7,999
(99.99%) 0.001 5 x 10-10
Decomposers 20,001 18,183 1,818 9.09 80
(4.40%) 1,738 0.102
This chapter discusses the ecological relations ruling the “parasitism phenomenon” and analyzes them according
to paleoparasitological interpretations of paleontological and archaeological finds. We specifically present a line of
research focusing on mites and ticks from the past. Didactically, but no less technically and scientifically, we describe
these animals and their biological and anatomical similarities and differences between them and insects.
We also take an epidemiological approach to debate the importance of these invertebrates, emphasizing the
complexity of ecological models for the transmission of infectious agents by Acari. In order to review and describe the
records and reconstruct what may have occurred in the past, we conduct a systematic classification to establish the
conditions for interpreting the importance of paleoacarological finds and their ecological context.
PARASITES OF ARTHROPODS
Of all parasites, fossil or living, those of phylum Arthropoda (the largest phylum in kingdom Animalia) definitely
include the widest variety of forms, occupy the most different ecotopes, and display the widest range of biological
and parasitic behavior (Giribet & Ribera, 2000; Hickman, Roberts & Larson, 2006; Serra-Freire & Mello, 2006).
The group is highly heterogeneous, but with the following basic morphological characteristics: a segmented or
metameric body, bilateral symmetry, jointed appendages (including for locomotion), and a chitinous or sclerotized
exoskeleton (chitin is a stiff, resilient, and water-insoluble nitrogenated polysaccharide, and sclerotin is another
nitrogenated polysaccharide, resilient yet pliable, but also water-insoluble). In geological time, the evolution of
Arthropoda began in the Paleozoic, in the Cambrian period or even earlier (Pre-Cambrian), more than 600 million
years ago (Weygoldt, 1998).
Mites, Ticks, and Paleoparasitology
173
An in-depth analysis of the debate on the phylogenetic origins of arthropods is beyond the scope of this chapter
(many authors defend a monophyletic origin, i.e., that all arthropods originated from a common ancestor on the
evolutionary scale) (Weygoldt, 1998). Briefly, however, two major groups (subphyla) are recognized as having emerged
from Arthropoda: the group of Mandibulata, which have mandibles as part of their mouthparts, and the group of
Chelicerata, which have six pairs of jointed appendages, with one pair of chelicerae, a pair of leg-like appendages or
pedipalps, and four pairs of walking legs (Hickman, Roberts & Larson, 2006).
The subphylum Mandibulata, which some authors classify as subphylum Uniramia, includes the following
respective subgroups: Crustacea (with a hard “crust”-type carapace and two pairs of antennae), Myriapoda (“a
thousand legs, feet”, or walking appendages), and Hexapoda (three pairs of legs). In subphylum Chelicerata, one of
the largest classes is Arachnida (head fused to the thorax – cephalothorax and abdomen, no antennae or mandibles),
which includes mites and ticks (Weygoldt, 1998; Wheeler & Hayashi, 1998; Giribet & Ribera, 2000; Hickman, Roberts
& Larson, 2006). Among the mandibulates and chelicerates, two groups have great parasitological importance for
both human and veterinary medicine: class Insecta (insects) and class Arachnida (which includes the mites and ticks).
EPIDEMIOLOGICAL IMPORTANCE, PRESENT AND PAST
Many of these arthropod species can serve as winged or wingless vectors in epidemiological transmission chains,
as mechanical and biological transmitters of infectious agents (e.g., viruses, rickettsiae, bacteria, protozoa, fungi, and
helminths). Through their bites and blood meals they inoculate and participate in the dissemination and dispersal of
pathogenic bioagents to susceptible organisms, thus leading to diseases. Different processes can occur, depending on
various other factors related to the time between emergence of cases and the characteristics of the geographic space
in which they take place. Such processes can be epidemic (e.g., exanthematic typhus, Brazilian spotted fever, scabies),
endemic (Lyme disease, babesiosis), or pandemic (rickettsiosis, ixodidiosis). Epidemiologically, they can also act as
reservoirs and intermediate hosts of these same potentially pathogenic agents for humans and species of domestic
and wild animals (Rey, 2001; Forattini, 2004; Coura, 2005).
Blood-feeding insects, mites, and ticks (adult ectoparasites and their larval and nymphal forms) are also responsible
for debilitation through infestations such as botfly lesions, myiases, and other dermatoses. Considering the serious
social and economic impacts of these diseases in modern times, especially in developing countries, one can imagine
their impact on human and animal populations in the past.
Importantly, the dynamics of infectious diseases involve complex ecoepidemiological chains, which combine with
socioeconomic and cultural determinants of infectious processes to directly or indirectly affect humans; humans also
help generate such processes (through anthropogenic actions). When these processes involve humans and other
animals (zoonoses) and arthropod vectors, the biological and parasitic relations become highly intricate (Coura, 2005).
THE PALEOSCENARIO AND PALEOPATHOCENOSIS
Vectors transmit parasites to their vertebrate hosts during feeding (blood meals or hematophagy). The biological
characteristics (anatomical, physiological, and behavioral) of Acari are different from those of Insecta. Distinct
biological attributes, including adaptive responses to biotic and abiotic factors in the environment, determine
differences between these groups in their epidemiological performance as vectors (Randolph, 1998). The latter
Foundations of Paleoparasitology
174
author thus proposes that systems of parasite transmission by vectors that are used for insects should not be
applied to mites (and especially not to ticks).
Parasitic strategies display similarities between distant phylogenetic groups – strategies considered in studies of
systematics and phylogenetics (Poulin, 1995). However, the spatial distribution (dispersal and diffusion), temporal
distribution (seasonality), and density of vectors and susceptible individuals (among other factors) determine the
survival and perpetuation of many vectors (during the non-parasitic phase) and thus their success in reaching a new
host. The risks of infection to animal and human hosts were and are directly related to their parasitic and vector
strategies. Importantly, the establishment of the parasite-host relationship depends on the entire complex ecological
dynamics of these hosts (Poulin, 1995; Randolph, 1998; Coura, 2005).
ACAROLOGY
Studies on mites and ticks were traditionally included within entomology (the field of biology/zoology that studies
insects). However, mites and ticks do not fly. At most, tick larvae perform aeronautism (moving on the wind, i.e., by
aeolian force), thus constituting a spatial strategy to guarantee their dissemination and long-distance dispersal. The
fact that they are wingless is only one of many differences in relation to insects.
Acarology is thus the field of zoology that studies invertebrate organisms belonging to subclass Acari. These are
chelicerates that have an undivided body (idiosoma) – the fusion of the cephalothorax and the abdomen – and the
mouthparts forming another set, the gnathosoma or capitel connected to the idiosoma. Signs of primary segmentation
are present in the embryonic phase during metamerization (Oliveira & Serra-Freire, 1994), and can be seen in the
post-embryonic phase in the sulci of the exoskeleton (Serra-Freire & Mello, 2006). Three major lineages are accepted:
Opilioacariforms, Parasiforms (the latter constituting the cohort of Parasitiforms Reuter, 1909), and Acaritiforms,
forming the cohort of the same name. The first is considered the most primitive lineage of mites. At present, the
members of the other two are important for human and veterinary medicine and are the most extensively studied.
The following are the main classical characteristics used and accepted by most acarologists for purposes of
taxonomic identification, and which we find practical and didactic (Flechtmann, 1975; Hickman, Roberts & Larson,
2006; Wooley, 1988; Oliver, 1987 apud Serra-Freire & Mello, 2006; Dunlop & Alberti, 2007; Krantz & Walter, 2007):
•Parasitiformcohort:formsthatpresentrespiratorystigmataontheposteriortagma(hysterosoma)andsensory
organs on the propodosoma. Ticks and mites are included. Another characteristic that served as the basis for
classifying them as superorder Anactinotrichida is the nature of the cuticle, optically inactive, since it does not
stain with iodine. This cohort includes the following orders: Opilioacarida Hammen, 1968, the most primitive
Acari, which colonize semiarid spaces; Holothyrida Thon, 1909, which are lethal to birds and highly toxic to
humans both by contact and when ingested; Ixodida Leach, 1815, which survive and reproduce on the blood
they obtain from hosts; and Gamasida Hammen, 1968, which includes parasitic, predatory, and free-living
decomposer species.
•Acariform cohort: forms that do not present respiratory stigmata on the hysterosoma, and in which the
propodosomal sensory organs either do not exist, or when present, take the form of trichobothria, or more
specialized structures such as rhabdomeres. This cohort constitutes the group of mites per se. Under the other
systematic classificatory proposal, the group belongs to superorder Actinotrichida, since the cuticle is optically
active – staining a yellowish color with iodine. This cohort includes the following orders: Astigmata Canestrini,
Mites, Ticks, and Paleoparasitology
175
1891, which includes the majority of bioagents for scabies in animals and humans; Oribatida Hammen, 1968,
including an extremely wide variety of decomposer mites that serve as intermediate hosts to helminth parasites
of vertebrates; Actinedida Hammen, 1968, with the widest biological diversity among the Acari, with predatory
species, parasites of vertebrates and invertebrates, and free-living species, including many decomposers.
Decomposers are important in the energy pyramid because they reinsert energy (that would otherwise have been
lost) to recirculate among living beings (Chart 1).
In the acarological literature, the most detailed textbook on Acari taxonomy is A Manual of Acarology (Krantz,
1978), which provides classification keys down to the family taxon, including information on their biology, behavior,
evolutionary relations, and economic importance. This work has now been replaced by the latest edition, presenting
the most recent concepts on the classification of mites (Krantz & Walter, 2009). According to this more recent
systematic proposal, for example, the Acariforms are only divided into the orders Prostigmata (= Trombidiforms)
and Sarcoptiforms.
Considering the geological time scale (Figure 1), the Acari are an ancient group belonging to the Upper Devonian
(390 million years BP). These primitive mites were also considered terrestrial forms and classified as the single species
Protacarus crani by Hirst in 1923 (Poinar & Poinar, 1998). Studies on the origin and formation of the current groups
of Acari show that they probably had Euripterides as their ancestors in the Ordovician period (Serra-Freire 2003),
and that ticks appeared on the evolutionary scale at a time that coincided with the evolution of primitive reptiles.
Mites and ticks form the largest diversified known group among the Arachnida, with slightly more than 48 thousand
species (Harvey, 2002 apud Dunlop & Alberti, 2007). Currently, a list of 889 valid names is proposed for tick genera
and species (Barker & Murrell, 2004), although there is no consensus on acarological systematics, and other proposals
exist for their taxonomic classification (Horak, Camicas & Keirans, 2002), especially when molecular, biochemical,
and numerical systematics are considered, often disconnected from the classical morphological and morphometric
taxonomy with biological considerations.
PALEOACAROLOGY
Parasitic infections and diseases that affected populations in the past can be diagnosed and studied by finding
parasites, their evolutionary forms and their signs, in human and animal vestiges or remains found in archaeological
and paleontological material, as well as in historical documents (Ferreira, Araújo & Confalonieri, 1988; Araújo &
Ferreira, 1992). Paleoparasitology, a term proposed by Ferreira, Araújo & Confalonieri (1979), has emerged as a branch
of paleopathology (biological and health sciences) and is defined as the study of the parasite finds and their meaning
in material from the past (Araújo & Ferreira, 1997).
The specific study of the presence of parasite mites and ticks in ancient material is known as the branch of
paleoacarology. By relating Acari finds in prehistoric or historical material to their parasitic biological characteristics
and to the ecology of diseases caused by them or with bioagents for which they serve as vectors, one can infer the
importance of these arthropods in the epidemiological scenario of the past. Such studies also make an important
contribution to reconstruction of the paleofauna, possible ecological models, and the dynamics of existing infections.
Foundations of Paleoparasitology
176
Figure 1 – Chronology of animal life with evolution of the Arachnidae, Acari, Ixodida, and Ixodidae related to the evolution of the higher vertebrates
Mites, Ticks, and Paleoparasitology
177
A BRIEF HISTORY
In the historical context, mites and ticks have been known (or at least suspected) since Antiquity. Aristotle (355
BC) coined the term akari. In the 16th century, the Latinized term acari began to be used, giving rise to the genus called
Acarus siro by Linnaeus, in 1758, in his Systema Naturae (Dunlop & Alberti, 2007).
According to the historical review by Krantz (1978), the existence of parasites with ticks as vectors is suggested
by records of a “tick fever” in Egyptian papyri (Ebers Papyrus), dated to 1550 BC (Krantz, 1978; Obenchain &
Galum,1982). This was most likely a rickettsiosis (an infection caused by microorganisms of genus Rickettsia),
although the pathogen was only observed in tissue smears from ticks several millennia later, when ixodids were
identified as the vector in the epidemiological transmission chain for that infectious agent.
One of the first references to ticks is attributed to Homer in 850 BC, when he cited the presence of these ectoparasites
on Ulysses’ dog, Argus. Some 500 years later, Aristotle wrote about a mite of locusts (probably Eutrombidium),
thrombiculid mite larvae, and mites colonizing old beehives in his treatise De Animalibus Historia Libri. He was also
familiar with ticks of dogs, goats, sheep, and other domestic animals. He further claimed that ticks are generated from
“couch grass”.
Other ancient references to Acari appeared in the writings of Hippocrates, Plutarch, Aristophanes, and Pliny. The
latter, in 77 AD, in his treatise Historia Naturalis, cites an animal that lives off the blood of cattle and dogs, but never
of asses. The tick attaches its head to those animals, then swells up and bursts, engorged with its blood meal.
This quote indicates the existence of ticks and characterizes both their feeding habits and possible hosts. Mites and
ticks were frequently referred to as “lice”, “beesties”, or “little insects” during the Age of Darkness and Renaissance.
The terms akari and “mite” appeared around 1650 AD. As mentioned above, Linnaeus used the generic name “Acarus”
in the first edition of Systema Naturae, using the type A. siro in 1758 (Krantz, 1978).
Historically, after the formation of Ixodida on Earth, the evolutionary process maintained its course, and during
the Triassic Period, in the Paleocene Age, a major differentiation must have occurred, giving rise to the diversity we
know today, as illustrated in Figure 2.
The hypothesis presented in Figure 1 considers the absence of fossil evidence (so far) allowing a phylogenetic
evaluation of Arachnida in general or particular. However, there are indications that arachnids were already well
represented on Earth since the Middle Paleozoic – during the Devonian or Silurian period (Krantz, 1978). Furthermore,
the oldest fossil record of mites, Protacarus crani Hirst, dates to this time (440–360 million years). The record further
indicates that the greatest adaptive leap in Acari occurred during the Late Mesozoic (146 million years) (evolutionary
synergism) and Recent Cenozoic (65 million).
Foundations of Paleoparasitology
178
Figure 2 – Evolution of Ixodida from the Paleocene to present, considering their primary origin in trilobites
FOSSIL MATERIAL
Fossil records of insects are found in large numbers, but there are few mite and tick finds in paleozoological
studies. Fossils are defined as material remains of ancient living organisms or remains of their activities (ichnofossils
or trace fossils, e.g., trails, tracks, coprolites, tubes, perforations). To be considered fossils, organic remains must date
to more than 13,000 BP, corresponding to the last glaciation.
Fossilization (chemical and physical modifications that occur over a period of time) is a rare and complex event
(less than 1% of situations) that allows the preservation of evidence (remains) of the remote existence of living
organisms. The process consists of the substitution of dead organic compounds with other more stable ones like
calcite, silica, pyrite, carbon, and others. Usually only the hard parts (trunks, shells, carapaces, bones, and teeth)
undergo fossilization.
There are various modes of fossil transformation: unaltered preservation (inclusion in amber), recrystallization
(growth of minerals or change in the crystalline structure), replacement or substitution (silicification), permineralization
Mites, Ticks, and Paleoparasitology
179
(filling of pores and cavities with mineral), carbonization, incrustation (covering with a mineral film), molds (casts),
or impressions (counter-molds and replicas) (De la Fuente, 2003; Oliveira & Serra-Freire, 2008). More specifically,
in relation to unaltered preservation, amber is a fossil resin produced by conifer trees that existed around the
Carboniferous Period (Paleozoic Age) – between 280 and 345 million years BP – with the increasing predominance
of these plants during the Upper Permian – 250 to 280 million years BP. This fossil resin underwent limited chemical
alterations in relation to the original plant resin, and those in the Americas with preserved arthropods vary in age
from 15 to 150x106 years. The process occurred over time as follows:
arthropod trapped inside plant resin resin was buried
with the arthropod inside partial polymerization occurred
in the resin (copal) terpenes evaporated amber was formed
The principal tree species that released resins was the group of legumes, especially locust tree (genus Hymenaea),
which preserved many specimens in amber.
Mites and ticks can also be found in ancient material inside natural cavities (nasal fossae and diverticula,
auditory canals), or even on the surface (skin, hairs) of naturally mummified bodies. They can also be found in
both the stomach content of mummified animals and in coprolites. Unlike fossils, specimens can be recovered in
these conditions in paleontological or archaeological material that dates more recently than the 13,000 years that
characterizes fossilization.
PALEOACAROLOGICAL RECORDS
Concerning fossil Acari finds, we present the records in the scientific literature based on the review by Guerra
(2002). To date, the latter is the first thesis on the subject in Brazil. The researcher’s doctoral dissertation featured an
ecological analysis of mites associated with coprolites recovered from an archaeological site in Northeast Brazil. We
will also cite other reviews, in addition to more current records, in order to provide an overview of paleoacarology and
the meaning of its findings. We opted to present them according to the systematic classification for Acari, i.e., first the
paleoacarological records on members of the Parasitiform cohort, followed by the Acariform cohort.
The greatest adaptive advance in Acari occurred during the Late Mesozoic (146 x 106 years) (evolutionary
synergism) and Recent Cenozoic (65 x 106 years) (Krantz, 1978). Among the Parasitiforms, various specimens from
the orders Holothyrida, Gamasida, and Ixodida were found from the Mesozoic to the Cenozoic, beginning at 245 x 106
years, according to a review article by Krivolutsky & Druk (1986), when dinosaurs, mammals, and modern groups of
reptiles and amphibians appeared.
From order Ixodida (ticks), the following finds were recorded, in the reviews by Lane & Poinar Jr. (1986), Guerra
(2002), and De la Fuente (2003), shown in Chart 2.
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180
Chart 2 – Fossil tick finds according to taxa, host, stage, origin, and bibliographic reference for the genus
Genus and/or species Current hosts for genus aStage/ Sex (Family) Origin b (x 106 years) References
Carios jerseyi Birds, mammals Larva (Argasidae) New Jersey amber
(Cretaceous, 90-94) Klompen & Grimaldi, 2001
Ixodes succineus Birds, mammals Female (Ixodidae) Baltic amber
(Tertiary, 35-50) Weidner, 1964
Ixodes spp. Birds, mammals Larva
(Ixodidae)
Baltic amber
(Tertiary, 35-50) De la Fuente, 2003
Hyalomma spp. Mammals, reptiles, birds Male
(Ixodidae)
Baltic amber
(Tertiary, 35-50) De la Fuente, 2003
Amblyomma
(A. testudinis)Reptiles, birds, mammals Male
(Ixodidae)
Dominican amber
(Tertiary, 35-50) Lane & Poinar, 1986
Amblyomma spp. Amphibians, reptiles, birds,
mammals
Larva
(Ixodidae)
Dominican amber
(Tertiary, 15-40) Poinar, 1992
Amblyomma spp. Amphibians, reptiles, birds,
mammals
Larva
(Ixodidae)
Dominican amber
(Tertiary, 15-40) Amberdepot Inc.
Unknown Unknown 28 1st instar larvae
(Ixodidae)
Dominican amber
(Tertiary, 15-40) Amberdepot Inc.
Amblyomma spp. Amphibians, reptiles, birds,
mammals
Adult
(Ixodidae)
Dominican amber
(Tertiary, 15-40) Amberdepot Inc.
Unknown Unknown Adult
(Argasidae)
Dominican amber
(Tertiary, 15-40) Amberdepot Inc.
Ornithodorus antiquus Amphibians, reptiles, birds Female
(Argasidae)
Dominican amber
(Tertiary, 15-40) Poinar, 1995
Ixodes terciarius Birds, mammals Not reported
(Ixodidae)
Not reported
(Tertiary, Oligocene, 30) De la Fuente, 2003
Dermacentor reticulatus Mammals Male
(Ixodidae)
Auditory canal of wooly rhinoceros
(Tertiary, Pliocene, 2-5) De la Fuente, 2003
Amblyomma spp. Amphibians, reptiles, birds,
mammals
Larva
(Ixodidae)
Felid coprolites
(Holocene, 11,000 yrs.)
Guerra et al., 2001;
Guerra, 2002
Ixodes spp. Birds, mammals Larva
(Ixodidae)
Felid coprolites
(Holocene, 11,000 yrs.)
Guerra et al., 2001;
Guerra, 2002
a List of hosts from Klompen et al. (1996).
b Age of amber deposits from Poinar (1992), except for New Jersey amber deposit (Klompen & Grimaldi, 2001).
Source: Adapted from De la Fuente (2003).
Evaluating the impact of the finds listed in Chart 2, we begin by analyzing the finding of Ornithodorus antiquus,
described by the author, who also found remains of feces and fibrous plant material included in amber (Poinar,
1995). Poinar (1995) emphasized that the material’s characteristics, in addition to knowledge of the tick’s life
cycle, allow suggesting that the host was a rodent. According to the author, these ticks may even have been vectors
of spirochetes, considering the current epidemiological models in which many species of genus Ornithodorus are
vectors of these microorganisms.
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181
The Carios jerseyi larva finding (Klomplen & Grimaldi, 2001) does not mention the larval instar of this argasid
tick. According to current knowledge on representatives of Argasidae, the larval stage is the only one that remains
attached to the host for several days, until engorging. Fasting larvae remain in hiding places in the nests of hosts,
mostly Chiroptera mammals, which allows finding various larvae due to the etology of the stage; engorged larvae or
those with feeding interrupted by any cause could be isolated and far from the host’s nest, even very far away, being
transported by the winged host. A more detailed description is needed of the material preserved in the amber together
with the tick for a better understanding of the scenario, as done by Poinar (1995).
Guerra et al (2001) and Guerra (2002) found specimens of genera Amblyomma and Ixodes in felid coprolites from the
same archaeological site (Furna do Estrago) in the county of Brejo da Madre de Deus, Pernambuco State, Brazil. They
attributed the presence of ixodid ticks in felid coprolites to the animal’s predation of tick-parasitized prey. Occupation
of the site dates from 11,000 to some 2,000 years BP, during which the archaeological records show the presence of
hunter-gatherer groups in the region. In this region, presence of the following wild felids has been described: jaguar
(Panthera onca), mountain lion (Puma concolor), jaguarundi or eyra cat (Herpailurus yagouaroundi), and oncilla or
little spotted cat (Leopardus tigrinus). Also described are animals from the following families: Myrmecophagidae
(anteater), Cervidae (deer), Caviidae (capybara, rock cavy, guinea pig), Taiassuidae (peccary), and Echimyidae (spiny
rat), all considered prey of those felids.
Most fossil ticks have been recorded in amber from the Baltic or the Dominican Republic, from deposits where the
largest number of fossilized specimens have been studied. According to De la Fuente (2003), many pieces of amber
containing tick specimens are mined and sold by amber traders, sometimes without allowing correct classification of
the inclusions. Numerous ticks may have gone undiscovered because the amber pieces are in the hands of merchants
and private collectors, unbeknownst to the scientific community.
The finding of Dermacentor reticulatus in the auditory canal of a woolly rhinoceros (Schille, 1916) from 2-5x106
BP is interesting in light of current knowledge on Ixodidae. In relation to the taxonomic position, there are persistent
scientific discussions on the validity of the genus. Some experts include it as a subgenus of genus Dermacentor.
From the morphological point of view, the strong taxonomic character to separate the two genera is the number of
aeropiles on the peritrematic plate (Serra-Freire & Mello, 2006). The number has been shown to vary from 6 to 15 in
Anocentor nitens (Gazeta & Serra-Freire, 1995, 1996; Gazeta et al., 2001), with bilateral asymmetry and the possibility
of regional variation and cline formation, while in Dermacentor spp. there are always more than two dozen aeropiles.
Another difference is the preference for the site of parasitism in the host, which for A. nitens is the auditory canal
both in equids and felids (Flechtmann, 1975; Amaro et al., 1999), while genus Dermacentor displays a preference for
non-cavitary areas on the host’s skin. Such differences, taxonomic and in parasite etology, can raise the following
question: could A. nitens descend from D. reticulates in terms of behavior? A possible attempt to answer this question
would be studying this fossil’s peritrematic plate. In the context of this paleoacarological finding, one intriguing doubt
remains: why was only the male tick found in the site?
The conditions in which ixodids (hard ticks) are found in ancient material potentially leads to some epidemiological
inferences. Based on the accumulated knowledge from the 19th century to the present, hard ticks do not display nesting
habits, i.e., they do not live in hosts’ nests, dens, or shelters. Rather, they live in open habitats such as savannahs,
forest vegetation, scrub forests, and in the peri- or intradomicile. One exception is genus Ixodides, in which some species
display nesting behavior, like the argasids (soft ticks), which show nesting behavior, colonizing the nests of hosts.
Finding these ectoparasites indicates the antiquity of parasitism by ticks and the potential for transmission
of pathogenic bioagents vectored by them to animals and even to humans. Their presence in modern times helps
Foundations of Paleoparasitology
182
understand how the conditions in remote times were favorable and highlights their adaptive capacity. It is thus
important to know details of the climatic alterations that took place and thus the characteristics of the modern-day
biomass, including vegetation, and their hosts in order reconstruct what happened (the paleoscenario) or still happens
for the perpetuation or extinction of species.
In the Acariform cohort, most of the known fossils belong to order Oribatida. Members of this order are not
usually associated with other organisms such as other arthropods or vertebrates and humans. The known oribatids
are free-living mites and are the most predominant representatives of the edaphic (soil-dwelling) fauna, thus
present in forest ecosystems, observed in lichens, humus (facilitating cultivation of the soil), fungi, plants, and
as secondary fauna of decomposers. This diversity of habitats and niches in different ecosystems makes them an
essential compoment in recycling energy for the biomass, even in environments in which sunlight contributes
less to the energy pyramid (Chart 1). This group’s biodiversity is high when compared to Gamasida, Actinedida,
and Astigmata mites. Considering their feeding habits, species belonging to Oribatida are different. They are thus
classified among the macrophytophagous, microphytophagous, panphytophagous, coprophagous, zoophagous,
and necrophagous organisms (Wallwork, 1983).
The review by Krivolutsky & Druk (1986) lists records of oribatids in the Mesozoic (Jurassic and Cretaceous periods),
from 208 to 66 million years ago, and in the Cenozoic, Tertiary Period, in the Paleocene, Miocene, and Pleistocene
ages, from 66 to 1x106 years ago. The review shows the wide diversity and temporal distribution of these mites. Some
species died out, while others survived to this day, indicating that this group can be a reference for evolutionary
studies of mites. Chart 3 shows the records of mite finds in fossil material.
Chart 3 – Fossil mite finds according to taxa, niche, stage, origin, and bibliographic reference
Mites Current niche(s) Stage Origin References
Family Anoetidae Free-living mites Hypopus Coprolites from pelvis of mummified
body (Nevada, USA) Radovsky, 1970
Family Acaridae Free-living mites;
parasites of mammals Tritonymph Coprolites from pelvis of mummified
body (Nevada, USA) Radovsky, 1970
Family Lardoglyphidae Free-living mites;
stored products Hypopus Coprolites from pelvis of mummified
body (Nevada, USA) Radovsky, 1970
Family Cheyletidae Parasites of carnivorous and herbivorous
mammals; predators of arthropods Adults Hair and tissues from mummified body
(Minas Gerais, Brazil) Araújo et al., 1986
Order Astigmata Parasites of vertebrates;
free-living mites Adults and eggs Desiccated tissues of Peruvian and
Aleutian mummies Kliks, 1988
Family
Lardoglyphidae Free-living mites; stored products Not mentioned Intestinal content of North American and
Chilean mummies Baker, 1990
Order Actinedida
Family Tarsonemidae
Free-living mites; parasites of vertebrates,
invertebrates, and humans Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Gamasida Free-living mites; parasites of vertebrates,
invertebrates, and humans Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Astigmata
Family Atopomelidae
Free-living mites;
related to diseases in felids Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Mites, Ticks, and Paleoparasitology
183
Chart 3 – Fossil mite finds according to taxa, niche, stage, origin, and bibliographic reference (continued)
Mites Current niche(s) Stage Origin References
Order Astigmata
Family Acaridae
Free-living mites; parasites of felids,
cavies, and humans Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Astigmata
Family Glycyphagidae
Free-living mites;
related to diseases in felids Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Astigmata
Family Pyroglyphidae
Free-living mites;
related to diseases in cavies Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Astigmata
Anoetidae
Free-living mites;
related to diseases in felids Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Actinedida
Family
Tarsonemidae
Free-living mites;
related to diseases in felids and deer Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Oribatida
Family Hypochthoniidae
Free-living mites;
related to diseases in felids Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Oribatida
Family Cosmochthoniidae
Free-living mites;
related to diseases in humans and felids Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Oribatida
Family Ctenacaridae
Free-living mites;
related to diseases in felids Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Oribatida
Family Perlohmannidae
Free-living mites;
related to diseases in felids Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Order Oribatida
Family Eutegaeidae
Free-living mites;
related to diseases in felids Not mentioned Coprolites from Furna do Estrago
(Pernambuco, Brazil) Guerra et al., 2001
Some of records (up to Guerra et al., 2001) are quoted from the review by Guerra (2002). 7
According to Radovsky (1970), mites in the coprolites were probably transported to the feces by coprophilic insects.
Anoetid and acarid mites (order Astigmata) display free-living habits and are associated with stored products such as
grain, bran, and flour (Serra Freire & Mello, 2006) and can also be swallowed with food and eliminated in the excreta.
As for lardoglyphids, based on what is now known of their biology, they reached the body during the advanced
stage of desiccation, but before mummification. The presence of these mites suggests that the pelvic region did not
remain intact, but it is also possible that they either were ingested or entered the corpse through the anus. Remains
of saprophytic arthropods (which feed on dead matter) are frequently found in the intestinal content of mummified
human bodies but are not properly recorded (Kliks, 1988). The author goes on to state that they are ancient or
recent invaders of dead organic tissues. In the case of lardoglyphid mites found in the intestinal content of the
mummies examined by Baker (1990), the researcher states categorically that they were ingested with food, since in
the desiccation of the bodies a protein concentrate was found called pemmican (a mixture of meat jerky, raisins, lard,
and sugar). Besides the fact that the bodies showed no signs of orifices caused by insects, pemmican is consistent with
the feeding preferences of these mites.
The descriptions of mite specimens found by Guerra (2002) and listed in Chart 3 are classified at the family
level. For readers interested in species-level descriptions, we suggest directly consulting the researcher’s dissertation,
since her finds include mites from the family Tarsonemidae (order Actinedida). Representatives of this family are
Foundations of Paleoparasitology
184
generally associated with other arthropods (beetles), where the species display phoretic activity, or use arthropods for
transportation, or are even parasitoids (parasitizing other parasites). Considering the biology of these mites, we can
conclude that finding them in coprolites indicates that they invaded the excreta after defecation.
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