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hedgehogs, was due to larvae remaining entangled among the spines. This is, however, probably the typical life cycle in nature.

Nuttall summarized his findings as follows:

PERIOD DAYS

Preoviposition 6

Oviposition to hatching 35 (eggs at 18°C.)
Larval prefeeding period

7
Larva feeds 6
Premolting period 16 (larvae at 1990.)
Nymphal prefeeding period 7
Nymph feeds 6
20
7
6

Premolting period (nymphs at 18°C.)
Adult prefeeding period

Adult (female) on host
Total 116

This period Nuttall believed to be the shortest time required for completion of the life cycle. From 4300 to 15500 eggs were laid by single females; the higher number probably approximates the more common figure in nature. Females may remain alive as long as 26 days after oviposition; males live nmch longer. The longevity of the various stages, presumably unfed, in these ex. perients was 345 days for larvae, 89 days for nymphs, and over 421 days for some adults. Hosts were hedgehogs, guinea pigs, and rams. "

Subsequently, Nuttall (1915) noted that some adults were still alive 759 days after emerging. Females that had fasted for 817 days were fed on a ram, mated with males that had fasted over 210 days, and were ovipositing when the report was written. Three times as many females (253) as males (83) were counted in the pogeny of a single female.

Four years later, Nuttall (1919) observed that males may remain attached to one spot of the host for as long as 122 days. More comonly, however, after preliminary feeding for periods ranging from five to 29 days, they start wandering about in search of females. After mating, when females leave the host, males do

little if any wandering. If a female is placed near a male, con. siderable excitation is caused. A male may copulate with several females, but females apparently accept only a single male. Copu_ lation may be very swift or may apparently extend over several days. Females do not move from their feeding site until they drop from the host.

Ecology
See also section on HOSTS above.

In Algeria, adults are rarely seen in winter but begin to appear in March and continue till October, maximum densities being reached in April, May, and June (Algerian seasons are comparable to those of southern United States). Nymphs are found mostly during the summer. With slight variation, this seasonal picture is typical for H. marginatum wherever it oc_ curs.

In the Crimean forest Qlelnikova 1953) adults are found during the summer, March to September, but rare individuals (?most1y males) may be seen at any time of the year. Larvae and nymphs infest hares from the end of June to the first half of September. Nymphs are most common on hares in the latter part of August; for example, a hare on 2 August yielded 100 nymphs while another on 17 Augpst yielded 390 nymphs. In this forest reserve H. mar inatum = H. . lumbeum) occurs in all ecological zones_and in EII types-o forest. In pure stands of conifers, it is, however, comparatively rare. The nest

favorable habitats appear to be valleys with small open fields between the mountains.

In Transcaucasia, this species occurs equally in both high. land and forest zones and in desert and steppe formations and is found in every type of landscape in that area (Pomerantzev, Matikashvily, and Lototsky 1940). In Armenia, it occurs in the Artemesia semidesert of the Arax valley (Pomerantzev 1934) and at altitudes of 6500 feet and over (Lototsky and Popov 1934).

On the Crimean steppes, adults are most common in July Gfiay and June according to Kbrchatov l94QA). There, the greatest

density of this tick is around haystacks and in fallow fields where their immature stage host, the European hare, hides and feeds. Engorged nymphs drop from hares in autumn and overwinter in that stage. They molt in the spring, and adults attack cattle, sheep, horses, and man. The devastation of the Crimea during the war, followed by a great increase in hares and their ticks, was significant epidemiologically in the outbreak of highly virulent, often fatal hemorrhagic fever at that time.

REMARKS

Gynandromorphs of H. mar inatum have been described and il. lustrated by Pervomaisky . e same author (1949) was un.

able to secure a complete F1 generation from parthenogenetic fe. males of this species.

Schulze (l932C) illustrated certain of the cuticular sense organs of two of his "subspecies" of this species, also "gynetropes“, males with more dense punctations on the scutum con. forming to those of the female scutum in location and distribu.

tion. This species has been utilized in a study of sensory phy_ siology (Totze 1933).

when large numbers of ticks (as H. lumbeum) feed on a res.

tricted area of the host, the females-an some imes also males fail to engorge completely and may die; their development is far from normal. When different species are competing for the same feeding area, this additional competitive factor often hinders their normal development (Pavlovsky, Pervomaisky, and Chagin 1954) .

DISEASE RELATIONS

MAN: H. marginatum is considered to be the chief vector of the virus of Crimean emorrhagic fever. The extensive geographic

range of this tick and its large population in many areas where it occurs - factors that suggest a high potential as a medically important species - appear to be generally unappreciated outside of Crimea. This species is not involved in the transmission of Omsk hemorrhagic fever, since it does not occur in that area,

so far as is presently known.

Specimens naturally infected with Q fever (Coxiella burnetii) have been found; this species is a vector of the organism 553 transmits it through all stages including the egg.

Brucellosis or undulent fever organisms, Brucella melitensis,

survive some time in this tick, which is said 55 some Sdviet workers to be a carrier and transmitter of this pathogen. Some

Russian studies of ticks as animals sustaining natural foci of tularemia have negated the importance of H. marginatum (as H.

plumbeum) in this regard, altough other'wor ers ave reported £55 finding of naturally infected specimens.

CATTLE: Theileriasis (Theileria spp.).

HORSES: Theileriasis (Theileria egui) and piroplasmosis (Piro lasma caballi). Transovari transmission of the latter organism to the seventh generation has been demonstrated.

[graphic]

GUINEAPIGS: Rickettsiae pathogenic to these animals and transovarially transmitted to the F3 generation of H. marginatum have been reported.

IDENTIFICATIN

Males: The combination of characters for recognizing typical males is: (1) the center of the subanal shields is directly pos_ terior of the central axis of the adanal shields (which are large and broad); (2) the lateral grooves are long, reaching approximately to the eyes, but they are frequently somewhat obscured by dense punctations or by lack of discreteness, especially anteriorly;

(3) the scutal punctations are dense and large in the distal and scapular fields, but variable elsewhere, bein usually smaller and more shallow and less dense centrally; (4 the posteromedian groove reaches the scutal midlength, it is narrow anteriorly and wider posteriorly; the paramedian grooves are about half as long as the posteromedian groove and taper from a pointed apex to wide in the festoon area; a narrow heavily punctate ridge lies between the paramedian grooves and the lateral grooves.

The scutum is usually comparatively narrowly elongate, measuring approximately 4.0 mm. long and 2.5 mm. wide. Its color is typically dark brown to black, but reddish specimens also occur; the legs may be entirely reddish or reddish centrally on each segment with paler anterior and posterior bands (see next para. graph). The scutal punctations may be dense enough to suggest H. rufi s, but those in the center are shallower and smaller than eIsewhere, while in H. rufipgs they are deep and quite uni_ form in size and depth. The parma may appear to be merely a median festoon and is the same color as the rest of the scutum. The subanal and adanal shields have rounded contours; the adanal shields are quite large.

Heavily punctate males, as seen among series from Libya, Algeria, Egypt, Romania, and elsewhere may suggest H. turanicum (page 531). The legs of H. marginatum, however, lack the con.

spicuous enamelling charaEter1s 1c 0 those of H. turanicum.

[graphic]

Females: The genital apron is a large, robust widely trans. verse ov§I or triangle with a strongly bulging profile; it is most characteristic. The scutal punctation consists of numerous small, shallow, distant punctations over the entire surface (they may be almost medium size and slightly deeper and closer), and a few larger and deeper punctations scattered among them chiefly on the anterior half of the scutum. The basic punctation in some specimens is so shallow as to give scutum a rather smooth appear. ance, especially posteriorly. The central field between the oer. vical grooves is usually lighter (more reddish) than the dark lateral fields. The scutum appears to be exceptionally wide, its 1ength.width ratio being about equal or shorter than wide.

Females of H. umr 'natum and H. turanicum are quite similar but the bright enameIIlng of the 15g segments of H. turanicum distinguishes them. In most specimens of H. turafiicum tfie genital apron is not so widely triangular End the scutal punc_ tations are more numerous and discrete than in H. turanicum.

The larva and n m h of H. mar inatum have been described and illustrated By Bern s aia (I939C) and Feldman_Muhsam (1948).

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