Encyclopedia of Parasitology

2016 Edition
| Editors: Heinz Mehlhorn

Ixodes Species

Reference work entry
DOI: https://doi.org/10.1007/978-3-662-43978-4_1637

Name

Greek: ixos = clue, ixodes = clueing; Latin: ricinus = oil of a plant.

Synonyms

Hard ticks

Classification

Genus of  Ticks,  Acarina.

Important Species

See Table 1.
Ixodes Species, Table 1

Important Ixodes species found on humans

Species

Length (mm) of unfed adultsa

Hosts during development

Main hostsb

Disease (pathogens)c

Type of bite-transmitted pathogensc

Ixodes ricinus, Ixodes persulcatus

f 2.8–3.4 (7–8)

m 2.8–4

3

Dogs, cats, cattle,

Humans

Borreliosis, Ehrlichiosis,

Spring-summer encephalitis,

Redwater (Babesia divergens, B. microti)d

B

V

P

I. dammini d

 

3

Deer, cattle,

Borreliosis

B

I. pacificus

 

3

Humans

Encephalitis,

V

I. scapularis

 

3

Humans

Babesiosis

P

aSize of feed ticks in brackets

bHosts were selected according to important diseases; other hosts are possible

cThese pathogens do not occur in all hosts and may be transmitted by other tick species, too

dSome authors claim that I dammini is I scapularis, B bacteria, P protozoa, V virus, m male, f female

Life Cycle

See Figs. 1, 2, 3, 4, 5, 6, 7, and 8.
Ixodes Species, Fig. 1

Life cycle of Ixodes ricinus (as an example of a three-host tick, a-c). 1 Engorged females (4c) reaching a length of up to 1.5 cm drop down to the soil and over a period of 1 month they lay about 2,000 spherical to ovoid eggs which become attached to each other and thus appear as clusters on the soil. 2 6-legged larvae hatch from the eggs after 3–36 weeks (depending on the temperature) and creep onto the tops of grass blades, from where they attach to passing hosts (mostly small mammals, but also birds and humans; (a) 3 Fed larvae drop to the soil, and molt within 5–7 weeks (sometimes up to 5 months) to become 8-legged nymphs which at this point have no genital opening. Nymphs attack larger mammals and many other hosts (b), suck blood for 4–7 days and drop to the soil, where they molt within 2–8 months and become sexually mature adults (4a = male, 4b = unengorged female). Mostly in spring the adults attack larger mammals including humans (c), where especially females suck for 5–14 days. The whole development is temperature-dependent and requires about 2–3 years in Europe

Ixodes Species, Fig. 2

Unfed Ixodes ricinus female luring for hosts

Ixodes Species, Fig. 3

LM of a fully engorged female

Ixodes Species, Fig. 4

LM of female and male Ixodes ricinus in copula

Ixodes Species, Fig. 5

SEM of the anterior part of the capitulum of Ixodes ricinus showing the toothed sucking channel

Ixodes Species, Fig. 6

SEM of a larva of Ixodes ricinus from dorsal

Ixodes Species, Fig. 7

Two adult females of Ixodes laying eggs on plant leaves

Ixodes Species, Fig. 8

Micrographs of the different stages in the life cycle of Ixodes ricinus. (a) Larva, (b) nymph, (c) male, (d) female

Disease

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Institut für Zoomorphologie, Zellbiologie und Parasitologie, Heinrich-Heine-UniversitätDüsseldorfGermany