40 Liacarus 



5. Gen. Liacarus Michael*) 



1842 Oribates (part.). C. L. Koch, libers. Arach., v. 3 p. 99 ] 1855 Leiosoma 

 (non Stephens, Coleopt.. 1831!), Nicolet in: Arch. Mus. Paris, r.7 p. 439 j 1884 L., 

 Michael, Brit, Orib., v.l p. 273 1885 L., Canestrini, Prosp. Acarof., v.l p. 7 ! 1896 L., 

 Berlese, A. M. S., Crypt. II p. 58 | 1892 Liosoma, Trouessart in : Rev. Sci. nat. Quest, 

 .2 p. 48*. 



Body smooth. Last 3 pairs of legs inserted under the body. Ung. trid. 

 in all known species. 



9 good and 1 doubtful species. 



Key to the good species. 

 | Abd. oval, elongated 2. 

 \ Abd. as broad as long 6. 



f A central mucro beetwen the ant. ends of the Lam. 3. 

 \ No such mucro 5. 



f Mucro short, scarcely if at all passing points of C. lam. 4. 

 \ Mucro long, almost reaching tip of Rost. L. 1,25 mm 7. L. nitens . . . . p. 41 

 ( Psstg. org. fusiform with a terminal hair. L. 850 |u 1. L. coracinus . . . p. 40 

 4 ' Psstg. org. with short peduncle and globular head 



- L. 450 M 2. L. globifer . . . . p. 41 



- Abd. with a suture each side forming a'lat border. 



. J Psstg. org. long and setiform L. 880 |u . . 6. L. marginatus . . p. 41 

 \ Abd. without lat. border. Psstg. org. short and 



clavate. L. 650 (a 8. L. ovatus . . . . p. 42 



f Abd. globular (hemispherical) 7. 



) Abd. shield-shaped. L. 1,05 mm 4. L. lativentris ... p. 41 



f Abd. with 4 long hairs on post, margin L. 700 ju 5. L. longipilis ... p. 41 

 I Abd. hairless 8. 



Lam. far apart anteriorly connected by a slender 



Trlam. Psstg. org. clavate. L. 1 mm ... 9. L. palmicinctus . p. 42 

 Lam. joined anteriorly. Psstg. org. fusiform sessile. 



- L. 1,02 mm 3. L. globosus . . . p. 41 



1. L. coracinus (C.L.Koch) 1841 Oribates c., C.L.Koch, C. M. A., fasc. 31 

 t. 1 1885 Leiosoma c., Canestrini, Prosp. Acarof., v. 1 p. 21 j 1885 L. c., Berlese, A. M. S.. 

 fasc.' 20 nr. 3 ?1841 Oribates fuscus, C. L. Koch, C. M. A., fasc. 31 t. 2 | ? 1854 Oribates 

 politus, C. L. Koch & Berendt, Die im Bernstein befindlichen organischen Reste, v. 1 II 

 p. 110 t. 17 f. 112 ' 1855 Leiosoma similis, Nicolet in: Arch. Mus. Paris, v. 7 p. 442 t. 6 

 f. 2 j 1884 L. simile, Michael, Brit. Orib., v.l p. 276 t. 13 f. 1 7. 



Im. Dark brown, polished, Rost. with a small point on each side. 

 Cephth. much narrower than ant. margin of Abd. Dorso-vertex raised in 

 centre, raised part pointed anteriorly. Lam. blades slightly sinuate, their 

 ant. ends deeply indented, terminating in 2 curved points. Lam. hair spines 

 springing between the points and passing tip of Eost. Psstg. org. fusi- 

 form, sessile, terminated distally by a fine hair. Blades to femora 

 of all legs. Abd. a long ellipse truncated anteriorly, almost pointed poste- 

 riorly ; Dors, of Abd. polished, hairless, much arched ; anal covers large, 

 square, almost reaching post, margin. - - Nph. Almost colorless except tip 

 of Rost. and Tarsus, polished, oblong, Psstg. org. short fusiform. Dors, of 

 Abd. with a sparse marginal row of flexible hairs. - Im. L. ca. 850 |u, 

 a large variety ca, 1,1 mm, according to Berlese 1,5 mm. 



Algeria, England, France. 



*) The name Leiosoma Nicolet is preoccupied. The name I have used is derived 

 from Xetoq (smooth) and dxapi (acarus). A. D. Michael. 



