sides in the anterior portion. The same term is applied to lineal elevations present in some species on the dorsum of the basis capituli. LATERAL GROOVES: In males, the grooves running along the sides of the body, starting at or near the scapulae. They correspond to the marginal grooves found in females. LEGS: The two distal articles, the tarsus and metatarsus, are of value in describing the species. Length and shape are of some value. Measurements are made on the dorsal surface where the joint is fixed. On the ventral side the articulations telescope. In some species the tarsus tapers and has a nearly straight profile line on the dorsal side. In others the two sides are first nearly parallel and near the distal end may terminate in an even slope or in a hump followed by a depression. These profile lines, better shown in the drawings, are of value and show little variation within species. The "hump" when present seldom rises above the surface and yet if distinct, is spoken of as a hump. MACULA: A term used to designate the more heavily sclerotized portion of the median area of the spiracular plate which contains the principal respiratory orifice. MARGINAL BODY FOLD: In both sexes and in nymphs and larvae, the fold outside of the marginal (female) and lateral (male) grooves. MARGINAL GROOVE: In females, the groove which runs along the sides of the body starting at the postero-lateral border of the scutum. It corresponds to the lateral groove found in males. MEDIAN PLATE: In males, the median ventral plate situated just posterior to the genital aperture. MILLIMETERS: In this paper measurements are in millimeters and are indicated in numerals without repeating the usual "mm." "NECK": The connection between the basis capituli and the body, visible in some adult ticks. PALPUS: (pl. palpi) The movable, paired organs on the capitulum. The palpus is made up of four articles designated by numerals from 1 proximal to 4 distal. POROSE AREA: On the dorsum of the basis capituli in females, the paired depressions with floors which are pitted or irregular. They may be superficial or much depressed and vary in shape and size. POSTERIOR SPUR: Projection on palpal article 1 directed outward, diagonally or backward; better seen in ventral view. See also anterior spur. PRE-GENITAL PLATE: A ventral plate sometimes present in males and situated anterior to the genital aperture. PSEUDOSCUTUM: In males, the anterior portion of the scutum which corresponds with the scutum of the female. In many species it is not clearly demarked but is usually somewhat differentiated by faint surface markings or by punctations of a different size or disposition. PUNCTATIONS: Pits in the surfaces of the exoskeleton, present or absent on the scutum, basis capituli, palpi, ventral plates (in males), coxae, and legs. In Ixodes they are of various forms and sizes and are often difficult to distinguish from the modifications in the surface (not true punctations) where hairs occur, especially if the hairs have been broken off. Punctations may be tapering or rounded pits or large or small depressions with flat floors and vertical walls. Their relative numbers and sizes in different areas, especially on the scuta in females and ventral plates of males, are of value but in some species are particularly subject to confusing variation. RUGO-PUNCTATE: A commingling of punctation and wrinkles on the surface of some scuta. SALIENCE: An edge or corner that limits or projects, in contra-distinction to a rounded edge or corner. SCLEROTIZATION: The hardening, and incidentally, darkening of the body wall or its parts by deposit of sclerotizing substances in the cuticula. SCUTUM: (Pl. scutta) he dorsal shield of some aut rs. The anterior shield or plate posterior to the capitulum. In females, nymphs and larvae, it is short and occupies only a part of the dorsal surface but in males it occupies all of the dorsal surface excepting the marginal body folds. SPIRACULAR PLATE: The complex paired organ just back of coxa IV through which aeration is accomplished. The size, number, and disposition of goblets, the character of the surface, whether flat, convex or concave, and whether the macula is superficial or depressed are useful characters. Variation occurs in the size of the plate and to a less extent in its shape. The longer axis, especially in males, may be either longitudinal or transverse. TRANSVERSE SUTURAL LINE: A fused suture on the venter of the basis capituli present in some species. VENTRAL PLATES: In males, the plates in a definite pattern on the venter. Their relative sizes and shapes are useful as characters but in some species they show some variation. The number, sizes and distribution of the punctations are often useful. SCULPTUS NECK LATERAL CARINA PSEUDOSCUTUM LATERAL GROOVE MARGINAL BODY FOLD SCUTUM COOKEI AFFINIS ARTICLE I CONSTRICTION TRANSVERSE CAPITULUM SCAPULA LATERAL CARINA CERVICAL GROOVE NEOTOMAE CRENULATION LATERAL FILE Man CRENULATION とい H ہے E ARTICLE 3 ARTICLE 2 DENTATUS ANTERIOR SPUR LARTICLE I POROSE AREA CORNUA FILE I FILE 3 AURITULUS J FIGURE 1. Principal species characters of Ixodes. A. Dorsal view of male. B. Dorsal view of female. C. Ventral view of male. D. Ventral view of female capitulum. E. Dorsal view of female capitulum. F, G, H. Types of male hypostome. I. Female hypostome. J. Some types of structures visible in ventral view of basis capituli of females. BRUNNEUS IXODES LATREILLE, 1795 1795. Ixodes Latreille, p. 18. 1897. Ixodes Neumann, pp. 283, 325, 360, 384. 1899. Ixodes Neumann, p. 108. 1901. Ixodes Salmon and Stiles. p. 459. (Redescription and synonymy.) 1902. Ixodes Neumann, p. 115. (Genus Eschatocephalus maintained and that of Ceratixodes created.) 1904. Ixodes Neumann, p. 444 (Ixodes to include 3 subgenera: Euixodes, Ceratixodes, and Eschatocephalus). 1907. Ixodes Hunter and Hooker, p. 54. (Redescription and lists of U. S. species then known.) 1908. Ixodes Banks, pp. 22-23. (Redescription and 12 species described.) 1908. Ixodes Nuttall et al., p. 133. Anal grooves embracing the anus anteriorly and usually uniting in a point or arch. Always inornate and lacking eyes and festoons. Spiracles round or oval. Tarsi without spurs. Male scutum surrounded by a prominent body-fold and male venter with seven non-salient plates, namely, a pre-genital, a median, an anal, two adanal, and two epimeral plates. Attachment between palpal articles 1 and 2 movable. Sexual dimorphism marked especially in the hypostome, though rarely the hypostomes are similar. Type species, Acarus reduvius Linnaeus 1758. The placing of uriae White into a genus is a problem of long standing, and in summary it is well stated by Nuttall et al., 1911, p. 154, as follows: The main points whereby the genus Ceratixodes can be distinguished were originally stated to be: the convex inner surface of the palp, and the pointed extremity of the third palpal article in the female; the slightly hollow internal surface and swollen ends of the palps in the female; anal grooves of males as in Ixodes, but absent in the female; anal and adanal shields in the female. Neuman, 1904, p. 444, subsequently recognized that the female (I. putus q. v.) differed so slightly from other female Ixodes, that the genus could not be retained; the female was found to possess an anal groove and the male only differs from other male Ixodes in respect to its palps. He therefore degraded Ceratixodes to a subgenus. Still retained as a genus by Blanchard, 1909, p. 97. - The present writers see no sufficient reason for re-establishing Ceratixodes either as a genus or subgenus, though it is admitted that the ventral plates on the male are somewhat at variance with the definition of the genus as respecting the ventral plates. In the absence of the male, the female would still be difficult to place. (See figs. 3 and 87.) KEY TO FEMALES [The female of californicus is unknown.] 1. Hypostome with only files 1 and 2 extending the full length, files 3 never Hypostome with files 3 extending for more than half the length; files 4, 5, 2. Cornua present, distinct (fig. 41). Cornua short, indistinct or absent (fig. 30). 3. Lateral carinae on scutum distinct (fig. 41). Lateral carinae on scutum faint or absent (fig. 39). 4. Basis with posterior margin sinuous (fig. 41). Basis with posterior margin straight or evenly curved (fig. 50) 6. Cervical grooves faint or absent (fig. 50). Cervical grooves distinct (fig. 36) 7. Auriculae large, robust horns (New Mexico). Auriculae small, faint (Western States).. 8. Palpi long and narrow (Texas).. Palpi short and wide (Eastern States). 9. Scutum with postero-lateral margins nearly straight (Western States) Scutum with postero-lateral margins convex (Southeastern 13. Porose areas large and superficial (fig. 53) Porose areas small and depressed (fig. 47) 10. Unusual ticks: Coxa I with spurs robust, bifid (fig. 74) Coxa I with spurs not robust, bifid (North America, Canada, and Sub- 15. Scutum about as long as wide (California) Scutum distinctly longer than wide (Subarctic) 19. Lateral carinae on the scutum distinct (fig. 44) Lateral carinae on the scutum faint or absent (California) 5 6 dampfi (p. 159) diversifossus (p. 49) kingi (p. 131) ...conepati (p. 161) cookei (p. 91) 11. Coxa I with external spur much longer than internal spur (Panama, South America) luciae (p. 175) Coxa I with spurs about equal (Mexico and South America)....loricatus (p. 187) 12. Internal spur on Coxa I short or absent (fig. 30). Internal spur on Coxa I long (fig. 44) 20. Lateral carinae on dorsum of the basis distinct (Texas) Lateral carinae on dorsum of basis absent (fig. 66).. sculptus (p. 105) 7 8 Scutum with punctations less numerous and finer (fig. 60). 22. Auriculae as mild lateral extensions (Arkansas). Auriculae absent (Mexico and Panama). marmotae (p. 99) ...scapularis (p. 13) 11 23. Internal spur on Coxa I short or absent (fig. 84) Internal spur on Coxa I long (fig. 25).. 14. Lateral carinae present on the scutum (British Columbia)....ochotonae (p. 139) Lateral carinae absent on the scutum 15 12 13 19 16. Scutum about as long as wide (fig. 30)..... Scutum distinctly longer than wide (Eastern States) 17. Body very hairy (Subarctic) Body not noticeably hairy (United States and British Columbia) 18. Basis with a rounded hump each side of the hypostome (seen better in texanus (p. 77) ventral view) (United States) Basis lacking a distinct hump each side the hypostome (United States and hearlei (p. 85) 20 jellisoni (p. 41) woodi (p. 163) 21 14 16 4 9 howelli (p. 217) signatus (p.201) 21. Scutum with many large distinct punctations and with wrinkles on the antero-lateral area (Pacific Coast). rugosus (p. 119) 22 17 marxi (p. 125) uriae (p. 223) 18 24. Very small tick with longitudinal wrinkles on posterior portion of scutum (British Columbia and California). Larger ticks lacking the longitudinal wrinkles on scutum 25. Coxae with only traces of spurs, hypostome short, rounded apically (Arkansas) Coxae with distinct spurs, hypostome long, pointed (fig. 79). 26. Auriculae as pointed retrograde spurs, about as long as wide (fig. 68). Auriculae as angular or rounded lateral extensions (fig. 79).. soricis (p. 149) 25 baergi (p. 219) 26 27. Hypostome with files 4 present, extending at least half the length, these bequaerti (p. 173) mexicanus (p. 157) 28. Denticles 4/4 (Southern States). Denticles 6/6 (California). 29. Auriculae retrograde; definite, either broad and robust curved horns (fig. 25). 30. Denticles 6/6 (Eastern States). Denticles fewer than 6/6 (fig. 72). Auriculae not retrograde; indefinite or absent; when present, as rounded 32. Auriculae as retrograde horns (fig. 72). 35. Porose areas large, distinct (Eastern States). Porose areas small, faint (California). 31. Palpal article 1 large, conspicuous and with a distinct anterior projection 195 (North America). auritulus (p. 105) Palpal article 1 small and lacking an anterior projection (fig. 72). 32 36. Scutum longer than wide (Western States). Scutum approaching circular (fig. 8). brunneus (p.205) ..murreleti (p. 231) or as narrow margin (Central and South America). Scutum lacking this group of deep, distinct punctations. 39. Cornua absent (Pacific Coast).. Cornua present, small (Arkansas). 30 36 ..dentatus (p. 61) Auriculae as retrograde, short spurs (fig. 56). 33. Lateral carinae on scutum faint or absent (Central America)....bicornis (p.181) Lateral carinae on scutum present (fig. 20).... 34 34. Hypostome long and narrow (California) Hypostome long and moderately broad (Western States and British 37. Lateral carinae on scutum present (Mexico). Lateral carinae on scutum absent... 38. Scutum with a group of deep, distinct punctations near the posterior 5. Spiracular plate small, short, oval (Pacific Coast). Spiracular plate large, long oval (fig. 3).... 6. Length of body about 2.40 (Arkansas). Length of body about 1.89 (Southeastern States). ུ 31 neotomae (p. 35) 2. Hypostome with large lateral denticles conspicuous and well differentiated from the small median denticles which are in diagonal or transverse crenulations (fig. 3) Hypostome with smaller lateral denticles not well differentiated from the medians which may be in longitudinal files (as in females) or with small, mild teeth in indefinite files, or in diagonal transverse crenulations (figs. 26, 51).. 3. Coxa I with internal spur long (fig. 24).. Coxa I with internal spur short or moderate (fig. 21). spinipalpis (p. 51) ..muris (p. 145) peromysci (p. 45) angustus (p. 69) 37 ..tancitarius (p. 171) 38 KEY TO MALES Males of the following species are unknown: diversifossus, soricis, rubidus, mexicanus, dampfi, conepati, woodi, banksi, tancitarius, bequaerti, auritulus, signatus, brunneus, murreleti, californicus, howelli. 4. Median ventral plate with large deep punctations (Mexico and Central America) Median ventral plate with fine punctations. Basis broader than long, impunctate (California). 9. Median ventral plate punctate (California).. Median ventral plate impunctate (California). 33 35 1. Hypostome conspicuously bilobed apically; denticles few, faint and vestigial (Subarctic) (fig. 87)... .uriae (p. 223) Hypostome not conspicuously bilobed; denticles never few, faint and vestigial (figs. 35, 42).. 2 affinis (p. 29) 39 pacificus (p. 21) ..ozarkus (p. 57) 7. Coxa I with internal spurs moderately long; punctations on scutum numerous, distinct (fig. 21). 3 10 47 affinis (p. 35) 5 pacificus (p. 21) 6 ...ozarkus (p. 57) scapularis (p. 13) 8 9 Coxa I with internal spurs short; punctations or scutum few, faint, or absent (fig. 12). 8. Basis about as broad as long, punctate (Western States and British Columbia) spinipalpis (p. 51) jellisoni (p. 41) ..neotomae (p. 35) ..peromysci (p. 45) |