Handbook of Medical Entomology Part 31

gg. With eyes.

h. a.n.a.l groove distinct; posterior marginal festoons present.

i. Base of the capitulum (fig. 150c) rectangular dorsally; usually ornate. DERMACENTOR Koch.

j. Adults with four longitudinal rows of large denticles on each half of hypostome; stigmal plate nearly circular, without dorso-lateral prolongation, goblets very large, attaining 43 to 115 in diameter; not over 40 per plate, each plate surrounded by an elevated row of regularly arranged supporting cells; white rust wanting; base of capitulum distinctly broader than long, its postero-lateral angles prolonged slightly, if at all; c.o.xae T with short spurs; trochanter I with small dorso-terminal blade. Texas, Arizona, etc.

_D. nitens_

[Ill.u.s.tration: 151. Rhipicephalus bursa, male. After Nuttall and Warburton.]

jj. Adults with three longitudinal rows of large denticles on each half of hypostome; goblet cells always more than 40 per plate; whitish rust usually present.

k. Dorso-lateral prolongation of stigmal plate small or absent; plates of the adults distinctly longer than broad; goblet cells large, usually 30 to 85 in diameter, appearing as very coa.r.s.e punctations on untreated specimens, but on specimens treated with caustic potash they appear very distinct in outline; base of capitulum distinctly (usually about twice) broader than long, the postero-lateral angles distinctly produced caudad; spurs of c.o.xae I long, lateral spur slightly longer than median; trochanter I with dorso-terminal spur. _D.

albipictus_, (= _variegatus_), _salmoni_, _nigrolineatus_.

kk. Dorso-lateral prolongation of stigmal plate distinct.

l. Body of plate distinctly longer than broad; goblet cells of medium size, usually 17.5 to 35 or 40 in diameter, appearing as medium sized punctuations on untreated specimens, but on the specimens treated with caustic potash they appear very distinct in outline, which is not circular; base of capitulum usually less than twice as broad as long, the postero-lateral angles always distinctly prolonged caudad.

m. Trochanter I with distinct dorso-subterminal retrograde sharp, digitate spur; postero-lateral angles of capitulum p.r.o.nouncedly prolonged caudal, 112 to 160 long; goblet cells attain 13 to 40 in diameter; type locality California. D.

OCCIDENTALIS

mm. Trochanter I with dorso-terminal blade; postero-lateral angles of capitulum with rather short prolongations.

n. Stigmal plate small, goblet cells not exceeding 45 in the male or 100 in the female; scutum with little rust, c.o.xa I with short spurs, the inner distinctly shorter than the outer. _D.

parumapertus-marginatus_

nn. Stigmal plate larger; goblet cells over 70 in the male and over 100 in the female; c.o.xa I with longer spurs, inner slightly shorter than the outer; scutum with considerable rust. D. VENUSTUS[F]

ll. Goblet cells small, rarely exceeding 17.6, occasionally reaching 19 in diameter; on untreated specimens they appear as very fine granulations, and on specimens treated with caustic potash they may be difficult to see, but their large number can be determined from the prominent stems of the goblets; surface of outline of the goblets distinctly circular; base of the capitulum usually less than twice as broad as long, the postero-lateral angle distinctly prolonged caudad; spurs of c.o.xae I long. _D. reticulatus_ and _electus_ (= _variabilis_?)

ii. Base of the capitulum (fig. 151) usually hexagonal (except in the male of _puch.e.l.lus_); and usually inornate.

j. No ventral plate or shield in either s.e.x (fig.

153). R. BICORNIS from the United States.

RHIPICENTOR Nuttall

jj. Males with a pair of ada.n.a.l shields, and usually a pair of accessory ada.n.a.l shields. Numerous species, among them _R. sanguineus_ (fig. 154) and _texa.n.u.s_, the latter from the United States.

_Rhipicephalus_ Koch

hh. a.n.a.l grooves faint or obsolete; no marginal festoons.

i. Short palpi; highly chitinized; unfed adults of large size; c.o.xae conical; male with a median plate prolonged in two long spines projecting caudad; segments of leg pair IV greatly swollen (fig. 155, 156). _M. winthemi_ _Margaropus_ Karsch

[Ill.u.s.tration: 152. Monieziella (Histiogaster) emtomophaga-spermatica, ventral aspect, male and female. After Trouessart.]

ii. Very short palpi, ridged dorsally and laterally; slightly chitinized; unfed adults of smaller size; c.o.xae I bifid; male with ada.n.a.l and accessory ada.n.a.l shields (fig. 139). B. ANNULATUS. BOOPHILUS Curtis

ff. Palpi longer than broad (fig. 157).

g. Male with pair of ada.n.a.l shields, and two posterior abdominal protrusions capped by chitinized points; festoons present or absent. Several species, among them H. aeGYPTIc.u.m (fig. 140) from the old world. HYALOMMA Koch

gg. Male without ada.n.a.l shields but small ventral plaques are occasionally present close to the festoons. Many species, a few from the United States (fig. 157).

AMBLYOMMA Koch

h. c.o.xa I with but one spine; metatarsi (except I) with two thickened spurs at tips. _A. maculatum_

hh. c.o.xa I with two spines; metatarsi without stout spurs at tips, only slender hairs.

i. Projections of c.o.xa I blunt and short. Large species on the gopher tortoise in Florida. _A. tuberculatum_

ii. Projections of c.o.xa I longer, and at least one of them sharp pointed; second segment of palpus twice as long as the third; c.o.xa IV of the male with a long spine.

j. Porose areas nearly circular; shield of both s.e.xes pale yellowish, with some silvery streaks and marks, and some reddish spots; shield of female as broad as long. A. CAJENNENSE (= MIXTUM).

jj. Porose areas elongate, shield brown, in the female with an apical silvery mark, in the male with two small and two or four other silvery spots; shield of the female longer than broad (fig 158 e). A.

AMERICANUM.

[Ill.u.s.tration: 153. Rhipicentor bicornis, ventral aspect, male. After Nuttall and Warburton.]

cc. Hypostome small, without teeth, venter without furrows; body often with coriaceous shields, posterior margin of the body never crenulate (i.e. without festoons); no eyes. GAMASOIDEA.

d. Parasitic on vertebrates; mandibles fitted for piercing; body sometimes constricted. DERMANYSSIDae.

e. a.n.a.l plate present. DERMANYSSINae.

f. Body short; legs stout, hind pair reaching much beyond the tip of the body. On bats. _Pteroptus_ Dufour.

ff. Body long; hind legs not reaching beyond the tip of the body.

g. Peritreme on the dorsum, very short; body distinctly constricted. _Ptilonyssus_ Berl.

gg. Peritreme on the venter, longer; body not distinctly constricted.

h. Mandibles in both s.e.xes chelate. Parasitic on bats, mice and birds (fig. 150, h). LIPONYSSUS Kol.

The species L. (= LEIOGNATHUS) SYLVIARUM frequents the nests of warblers. An instance is on record of these mites attacking man, causing a pruritis.

hh. Mandibles in the male chelate, in the female long, styliform (fig. 158 j). Parasitic on birds.

DERMANYSSUS Dug. Two species of importance may be noted, _D. hirundinus_ and D. GALLINae. The latter (fig. 51) is a serious pest of poultry, sometimes attacking man, causing itching and soreness.

ee. a.n.a.l plate absent. In lungs and air pa.s.sages of some mammals. HALARACHNINae.

dd. Free or attached to insects, rarely on vertebrates.

e. First pair of legs inserted within the same body opening as the oral tube; genital apertures surrounded by the sternum.

On insects. UROPODIDae.