| abstract | The present paper gives descriptions of a new genus and two new species of chigger mites parasitic on rats from Yunnan Province.
Muritrombicula, gen. nov.
Type species: Muritrombicula dali, sp. nov.
Diagnosis: the new genus resembles genus Trombicula, but is distinguishable from the latter chiefly by the following morphological charaeters: SIF=4B-N-3-2100.0000, scutum with shoulder, and leg I without parasubterminal seta.
Muritrombicula dali, sp. nov. (fig. 1)
Idiosoma of engorged larvae measuring 592-605×384-403µ. SIF = 4B-N-3-2100.0000. fp=B-B-BBB. Scutum nearly trapezoid, with shoulder. Scutal surface with fine punctations. Sensillae filamentous, with minute barbs on proximal, distal with 13-16 long branches. PL>AM>AL. Dorsal setae 80-90 in number, arranged as 4-10-8-6-11-8-12-8-11-4-4=86 (holotype). Ventral setae 60-76 in number. Leg I without parasubterminal seta. Standard measurements of specimens average as follows (in µ): AW=59, PW=90, SB=34, ASB=31, PSB=15, SD=46, AP=33, AM=44, AL=42, PL =52, Sn=73, HS=48, DS=43-34, VS=30-34, IP=871.
Holotype and 2 paratypes, larvae, ex Rattus coxingi andersoni, from Yunnan, May 8, 1976; 7 paratypes, larvae, ex R. coxingi andersoni, from Yunnan, March 15, 1978.
Leptotrombidium (Leptotrombidium) nudisensillum, sp. nov. (fig. 2)
Idiosoma of engorged larva measuring 1052×750µ. SIF=7B-B-3-2111.0000. fp=B-B-BBB. Scutum nearly trapezoid in shape, anterior margin slightly biconcave, posterior margin with central portion deeply concave, surface with fine punctations. Sensillae filamentous, nude. PL>AM>AL. Dorsal setae 71-79 in number, arranged as 4-...... Ventral setae 40-52 in number. Coxal setae formula 1-2-1. Standard measurements of 6 specimens average as follows (in µ): AW=82, PW=103, SB=41, ASB=39, PSB=12, AP=35, AM=68, AL=51, PL=105, Sn=115, HS=105, DS=97-80, VS=63-75, IP=1373. Holotype and 5 paratypes, larvae, ex Rattus niviventer, from Yunnan, September 1973. All type materials are deposited in the Control and Research Institute of Epidemic Diseases of Yunnan Province. |