A NEW MONOTYPIC GENUS OF CHIGGERS 
AND FOUR NEW SPECIES OF QUADRASETA FROM VENEZUELA 
(ACARI: TROMBICULIDAE)' 
M. L. Goff and J. M. Brennan' 
Abstract.— Curebureia, n. gen., and its type-species, C. johnstoni, n. sp., are described. The genus Quadraseta 
Brennan, 1970, is redefined and a key to the 11 included species given. Four new species, Quadraseta tachirensis, 
holotype ex Akodon sp., Q. rotstieri, ex Proechhnys guyannensis, Q. mirandae, holotype ex Oryzomys albigularis, 
and Q. fakonensis, ex SylviUigus floridanus, are described. 
Four new species of Quadraseta Brennan, 
1970, and a new monotypic genus, all from 
Venezuela, are described and illustrated be- 
low. Hosts are small mammals. 
Collections were made under the direc- 
tion of Dr. Charles O. Handley, Smithsonian 
Institution, Dr. Vernon J. Tipton, Brigham 
Young University, and Dr. Conrad E. Yun- 
ker, Rocky Mountain Laboratory. Holotypes 
are in the collection of the U.S. National 
Museum of Natural History (currently 
housed at the Bishop Museum, Honolulu, 
Hawaii) and paratypes are there and in the 
collection of the Bishop Museum. All mea- 
surements are given in micrometers of the 
holotypes followed in parentheses by the 
means and extremes of the type series. 
Quadraseta Brennan 
Quadraseta Brennan, 1970: 1695; Brennan & Reed, 
1975: 62. 
Type-species.— Euschoengastia pazca 
Brennan & Jones, 1964: 700. 
Diagnosis.— Trombiculine larvae parasitic 
on small mammals and, occasionally, birds; 
legs 7-segmented; coxae unisetose; 2-3 gen- 
ualae I, genuala II and III; tibiala III; sub- 
terminala and parasubterminala I; 6 
branched setae in basal whorl of tarsus I. 
Scutum sparsely punctate; subrectangular, 
with sinuous anterior and posterior margins; 
5 setae; sensilla clavate to capitate. Eyes 
2/2. Cheliceral blades with tricuspid cap; 
palpal tarsus with 4B; palpal claw 3- 
pronged. 
Quadraseta tachirensis, n. sp. 
Fig. 1 
Type data.— Holotype and 7 paratypes 
from Tachira, San Cristobal, 21-III-1968, ex 
Akodon sp. (RML 53653); 2 paratypes, same 
data except 15-III-1968, ex Akodon bogo- 
tensis (RML 55933). 
Diagnosis.— Palpal setal formula 
B/B/BBB/4B; palpal claw 3-pronged; ga- 
leala B; 3 genualae I; 54 dorsal body setae; 
2 pairs of humeral setae; PL>AM>AL; 
PW/SD = 1.83. 
Description of species.— Larvae. Idiosoma: 
Measuring 290 x 235 in engorged specimen. 
Eyes 2/2, anterior larger, on ocular plate. 
Two pairs of humeral setae, measuring 44- 
46; 54 dorsal body setae, measuring 32-40, 
arranged 6-10-14-10-6-6-2; 2 pairs of sternal 
setae, anterior 37-40, posterior 28-31; 42 
preanal setae, 20-24; 20 postanal setae, 28- 
33; total body setae 124. Gnatho.sorna: Pal- 
pal setal formula B/B/BBB/4B; palpal claw 
3-pronged; galeala B; chela (27) with tricus- 
pid cap. Scutum: Sparsely punctate; ante- 
rior margin biconcave, posterior margin bi- 
convex; AM base in line with AL bases; SB 
anterior to PL bases; PL>AM>AL; sensilla 
capitate, head with setules; PW/SD = 
'Studies upon which this paper is based were supported in part by Department of Army contract DA-49-193-MD-2788 with the Smithsonian In- 
stitution. 
'Department of Entomology. Bishop Museum, P.O. Box 6037, Honolulu, Hawaii 96818, USA. 
501 
502 
GREAT BASIN NATURALIST 
Vol. 37, No. 4 
1.83. Scutal measurements: AW 47 (48, 47- 
49); PW 66 (66, 62-69); SB 22 (19, 17-22); 
ASB 22 (22, 20-23); PSB 14 (14, 12-16); AP 
25 (25, 24-27); AM 25 (29, 25-32); AL 23 
(26, 23-30); PL 41 (45, 41-48); sens. 34 x 15 
(35, 33-37 X 14-15). Legs: All 7-segmented 
terminating in a pair of claws and a claw- 
like empodium. IP = 670-710. Leg L 225- 
238; coxa with 1 branched seta (IB); tro- 
chanter IB; basifemur IB; telofemur 5B; 
genu 4B, 3 genualae, microgenuala; tibia 
8B, 2 tibialae, microtibiala; tarsus (56 x 21) 
19B, tarsala (14-15), microtarsala, sub- 
terminala, parasubterminala, pretarsala. Leg 
U: 205-220; coxa IB; trochanter IB; basife- 
mur 2B; telofemur 4B; genu 3B, genuala; 
tibia 6B, 2 tibialae; tarsus (50 x 19) 14B, 
tarsala (12-14), microtarsala, pretarsala. Leg 
lU: 240-255; coxa IB; trochanter IB; basife- 
mur 2B; telofemur 3B; genu 3B, genuala; 
tibia 6B, tibiala; tarsus (65 x 16) 15B. 
Remarks.— Qitadraseta tachirensis is sim- 
ilar to Q. pazca (Brennan & Jones, 1964) in 
having galeala B and 3 genualae I, but 
differs in having eyes on a distinct ocular 
plate, PW/SD = 1.83 (1.51 in Q. pazca), 
and arrangement of body setae. 
Additional specimens examined (40).— 
Fig. 1. Larva of Quadraseta tachirensis: (a) scutum; (b) leg I distal 3 segments showing specialized setae (mea- 
surements in micrometers) and bases of branched setae; (c) leg II, as above; (d) leg III, as above. 
Dec. 1977 
GOFF, BRENNAN: VENEZUELAN MITES 
503 
Guarico, 6.1.1968, 1 Zygodontomys sp. (7). 
Tachira, San Cristobal, 2-17-III-1968, 2 
Akodon sp. (20), 1 Akodon bogotensis (2), 1 
Onjzomys sp. (3), 1 Oryzomys albigularis 
(1), 2 Oryzomys minutus (6). Yaracuy, W of 
San Felipe, 8-XII-1967, 1 Oryzomys capito 
Quadraseta rotstieri, n. sp. 
Fig. 2 
Type data.— Holotype and 8 paratypes 
from Falcon, E of Maracaibo, ex Proechimys 
guyannensis (RML 53271), 13-V-1968. 
Diagnosis.— Palpal setal formula 
B/B/BBB/4B; palpal claw .3-pronged; ga- 
leala N; 2 genualae I, genuala II and III; 
genu I with 5 branched setae; tibiala III; 58 
dorsal body setae, arranged 8-8-10-6-10-4-6- 
6; sensilla clavate; PW/SD = 1.90-1.97. 
Description of species.— Larvae. Idiosoma: 
Measuring 400 x .305 in engorged specimen. 
Eyes 2/2, of equal size, on ocular plate. 
Two pairs of humeral setae, measuring 46- 
48; 58 dorsal body setae, measuring 32-41, 
arranged 8-8-10-6-10-4-6-6; 2 pairs of ster- 
nal setae, 30; 28 preanal setae, 20-26; 30 
postanal setae, 30-35; total body setae 124. 
Fig. 2. Larva of Quadraseta rotstieri: (a) scutum; (b) leg I distal 3 segments showing specialized setae (measure- 
ments in micrometers) and bases of branched setae; (c) leg II, as above; (d) leg III, as above. 
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GREAT BASIN NATURALIST 
Vol. 37, No. 4 
Gnathosoma: Palpal setal formula 
B/B/BBB/4B; palp'al claw 3-pronged; ga- 
leala N; chela (35-38) with tricuspid cap. 
Scutum: Sparsely punctate; anterior margin 
biconcave, posterior margin biconvex; AM 
base posterior to AL bases; SB anterior to 
PL bases; PL>AL>AM; sensilla clavate, 
head with setules; PW/SD = 1.90-1.97. 
Scutal measurements: AW 56 (56, 52-59); 
PW 73 (76, 73-80); SB 22 (24, 22-27); ASB 
23 (24, 20-27); PSB 14 (16, 14-17); AP 28 
(30, 28-35); AM 36 (36, 33-38); AL 38 (38, 
34-40); PL 55 (52, 48-56); sens, missing in 
holotype (43 x 13, 42-45 x 13). Legs: All 7- 
segmented, terminating in a pair of claws 
and a clawlike empodium. Onychotrictes 
absent. IP = 690-717. Leg L 235-245; coxa 
IB; trochanter IB; basifemur IB; telofemur 
5B; genu 5B, 2 genualae, microgenuala; 
tibia 8B, 2 tibialae, microtibiala; tarsus (57 
x 20) 20B, tarsala (15), microtarsala, sub- 
terminala, parasubterminala, pretarsala. Leg 
U: 218-220; coxa IB; trochanter IB; basife- 
mur 2B; telofemur 4B; genu 3B, genuala 
tibia 6B, 2 tibialae; tarsus (51 x 19) 14B 
tarsala 15; microtarsala, pretarsala. Leg III 
238-252; coxa IB; trochanter IB; basifemur 
2B; telofemur 3B; genu 3B, genuala; tibia 
6B, tibiala; tarsus (67 x 17) 15B. 
Remarks.— Quadraseta rotstieri is similar 
to Q. antillarum (Brennan, 1967) in having 
2 genualae I and 4 humeral setae, but 
differs in having palpal tibia BBB (BNB in 
Q. antillarum), PL>AL, and 5 branched 
setae on genu I. 
Additional specimens examined (18).— 
Falcon, E of Maracaibo, 13-15-V-1968, 3 
Akodon urichi (18). 
Quadraseta mirandae, n. sp. 
Fig. 3 
Type data.— Holotype and 9 paratypes 
from Miranda, 1 km N of Caracas, Que- 
brada Chacaito, ex Oryzomys albigularis 
(RML 52518), 18-V-1967. 
Diagnosis.— Palpal setal formula 
B/B/BBB/4B; palpal claw 3-pronged; ga- 
leala N; 3 genualae I; 68 dorsal body setae; 
2 pairs of humeral setae; PL>AM>AL; 
PW/SD = 1.80. 
Description of species.— Larvae. Idiosoma: 
Measuring 290 x 225 in engorged specimen. 
Eyes 2/2, anterior larger, on ocular plate. 
Two pairs of humeral setae, measuring 49- 
55; 68 dorsal body setae, measuring 40-50, 
arranged 10-6-8-10-10-6-10-6-2; 2 pairs of 
sternal setae, 34-40; 38 preanal setae, 30-35; 
22 postanal setae, 34-42; total body setae 
136. Gnathosoma: Palpal setal formula 
B/B/BBB/4B; palpal claw 3-pronged; ga- 
leala N; chela (37-40) with tricuspid cap. 
Scutum: Sparsely punctate; anterior margin 
shallowly biconcave; posterior margin shal- 
lowly convex; AM base slightly posterior to 
AL bases; SB anterior to PL bases; 
PL>AM>AL; sensilla clavate, head with 
coarse setules; PW/SD = 1.80. Scutal mea- 
surements: AW 61 (62, 60-64); PW 80 (81, 
73-90); SB 28 (28, 23-31); ASB 29 (28, 26- 
29); PSB 17 (17, 14-18); AP 38 (37, 34-39); 
AM 44 (48, 44-52); AL 35 (35, 33-37); PL 
55 (60, 55-64); sens. 55 x 13 (50, 47-55 x 
12-14). Legs: All 7-segmented, terminating 
in a pair of claws and a clawlike em- 
podium. IP = 883-910. Leg L 300-312; 
coxa IB; trochanter IB; basifemur IB; te- 
lofemur 5B; genu 4B, 3 genualae, micro- 
genuala; tibia 8B, 2 tibialae, microtibiala; 
tarsus (75 x 22) 19B, tarsala (18-20), micro- 
tarsala, subterminala, parasubterminala, pre- 
tarsala. Leg U: 270-280; coxa IB; trochanter 
IB; basifemur 2B; telofemur 4B; genu 3B, 
genuala; tibia 6B, tibiala; tarsus (68 x 22) 
16B, tarsala (18-20), microtarsala, pretarsala. 
Leg lU: 305-317; coxa IB; trochanter IB; 
basifemur 2B; telofemur 3B; genu 3B, gen- 
uala; tibia 6B, tibiala; tarsus (82 x 18) 15B. 
Remarks.— Quadraseta mirandae is similar 
to Q. flochi in having 3 genualae I, clavate 
sensillae and PL>AL, but differs in having 
tarsalae I and II longer (18-20, 14 and 15, 
respectively, in Q. flochi), posterior scutal 
margin evenly convex (biconvex in Q. 
flochi) and longer dorsal body setae (40-50 
in Q. mirandae and 25-30 in Q. flochi). 
Additional specimens examined (134).— 
NW of Orania, 1 Proechimys guyannensis 
(1). BohVar, E of Caicara, 1 P. guyannensis 
(2). Falcon, E of Mirimire, 2 Heteromys 
anomalus (2), 3 Monodelphis brevicaudata 
(20), 1 Zygodontomys sp. (2). Lora, N of El 
Tocuyo, 1 Echymys sp. (1). Miranda, Ca- 
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GOFF, BRENNAN: VENEZUELAN MITES 
505 
racas Country Club, 4 Didelphis marsupialis 
(36); 1 km N of Caracas, Quebrada Cha- 
caito, 1 H. anornahts (8), 6 Oryzomys al- 
bigiilaris (18). Sucre, E of Carupano, 1 H. 
anornalus (11), 1 M. hrevicaudata (5), 1 P. 
guyannensis (4), 1 Zygodontomys microtinus 
(1). Yaracuy, W of San Felipe, 2 M. hrevi- 
caudata (8). Zulia, Sierra de Perija, 1 P. 
guyannensis (2), 2 Proechimys sp. (3). 
Quadraseta falconensis, n. sp. 
Fig. 4 
Type data — Holotype and 12 paratypes 
from Falcon, W of Coro, 17-VII-1968, ex 
Sylvikigus floridanus (RML 53360). 
Diagnosis.— Palpal setal formula 
B/B/BNB/4B; palpal claw 3-pronged; ga- 
leala N; 3 genualae I; 34 dorsal body setae; 
2 pairs of humeral setae; AL>PL>AM; 
PW/SD = 1.84. 
Fig. 3. Larva of Quadraseta mirandae: (a) scutum; (b) leg I distal .3 segments showing specialized setae (mea- 
surements in micrometers) and bases of branched setae; (c) leg II, as above; (d) leg III, as above. 
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GREAT BASIN NATURALIST 
Vol. 37, No. 4 
Description of species.— Larvae. Idiosoma: 
Measuring 430 x 300 in engorged specimen. 
Eyes 2/2, anterior larger, on ocular plate. 
Two pairs of humeral setae, measuring 25- 
28; 34 dorsal body setae, measuring 19-26, 
arranged 8-10-8-6-2; 2 pairs of sternal setae, 
25-27; 18 preanal setae, 15-18; 18 postanal 
setae, 21-23; total body setae 78. Gnatho- 
sorna: Palpal setal formula B/B/BNB/4B; 
palpal claw 3-pronged; galeala N; chela (25) 
with tricuspid cap. Scutum: Sparsely punc- 
tate; anterior margin deeply biconcave, pos- 
terior margin biconvex; AM base in line 
with or slightly posterior to AL bases; SB 
anterior to PL bases; AL>PL>AM; sensilla 
capitate, head with fine setules; PW/SD = 
1.84. Scutal measurements: AW 44 (41, 37- 
44); PW 61 (57, 52-61); SB 12 (12, 10-13); 
ASB 22 (22, 20-25); PSB 9 (9, 8-10); AP 26 
(25, 22-27); AM 20 (19, 18-20); AL 37 (36, 
34-38); PL 32 (31, 28-32); sens, missing in 
holotype (24, 21-26, head 15 x 16). Legs: 
All 7-segmented, terminating in a pair of 
claws and a clawlike empodium. IP = 540- 
560. Leg I: 190-195; coxa IB; trochanter 
IB; basifemur IB; telofemur 5B; genu 4B, 3 
Fig. 4. Larva of Quadraseta falconensis: (a) scutum; (b) leg I distal .3 segments showing specialized setae (mea- 
surements in micrometers) and bases of branched setae; (c) leg II, as above; (d) leg III, as above. 
Dec. 1977 
GOFF, BRENNAN: VENEZUELAN MITES 
507 
genualae, microgenuala; tibia 8B, 2 tibialae, 
microtibiala; tarsus (43 x 17) 19B, tarsala 
(10-11), microtarsala, subterminala, para- 
subterminala, pretarsala. Leg II: 160; coxa 
IB, trochanter IB; basifemur 2B; telofemur 
4B; genu 3B, genuala; tibia 6B, 2 tibialae; 
tarsus (37 x 15) 14B, tarsala (13-14), micro- 
tarsala, pretarsala. Leg III: 190-205; coxa 
IB; trochanter IB; basitemur 2B; telofemur 
3B; genu 3B, genuala; tibia 6B, tibiala; tar- 
sus (55 X 12) 14B. 
Remarks.— Quadraseta falconensh shares 
the character of a nude lateral palpotibial 
seta with Q. antillamm (Brennan, 1967) but 
differs in having 3 genualae I. 
Key to Species of Quadraseta 
1. Two genualae I 2 
Three genualae I 5 
2(1). Palpal setal formula B/B/BNB antiUanim (Brennan, 1967) 
Palpal setal formula B/B/BBB 3 
3(2). Galeala branched azulae (Brennan & Jones, 1964) 
Galeala nude 4 
4(3). Genu I with 5 branched setae rotstieri, n. sp. 
Genu I with 4 branched setae trapezoides (Brennan & Jones, 1964) 
5(1). Galeala branched 6 
Galeala nude 7 
6(5). PW/SD>1.75 tachirensis, n. sp. 
PW/SD<1.55 pazca (Brennan & Jones, 1964) 
7(5). Two humeral setae mackenziei (Yunker & Brennan, 1964) 
Four humeral setae 8 
8(7). Sensilla clavate; more than 60 dorsal body setae 9 
Sensilla capitate, fewer than 50 dorsal body setae 10 
9(8). Tarsala I 18-20; dorsal body setae measuring 40-50 mirandae, n. sp. 
Tarsala I 14; dorsal body setae measuring 25-30 flochi (Brennan & Jones, 1960) 
10(9). Lateral palpotibial seta nude falconensis, n. sp. 
Lateral palpotibial seta branched macarenae (Brennan & Jones, 1964) 
Carebareia, n. gen. 
Type-species.— Carebareia johnstoni Goff 
& Brennan, n. sp. 
Diagnosis.— Trombiculine larvae. Palpal 
tarsus 4B; palpal subterminala absent; pal- 
pal claw 3-pronged; galeala N; chela with 
tricuspid cap; sensilla capitate; genuala I, 
genuala II and III absent; tibiala III; sub- 
terminala and parasubterminala I; no masti- 
setae on leg III. 
Remarks.— Carebareia is similar to Quad- 
raseta Brennan, 1970, but may be separated 
by having only 1 genuala I (2-3 in Quad- 
raseta), lacking genuala II and III and hav- 
ing slightly expanded dorsal body setae. 
Single genuala I and absence of genuala II 
and III also serve to separate Carebareia 
from Aitkenius Brennan, 1970, Ectonyx 
Brennan, 1960, Cheladonta Lipovsky, 
Crossley & Loomis, 1955, and Trombe- 
wingia Fonseca, 1955. Carebareia is similar 
to Kayella Vercammen-Grandjean, 1960, in 
having 1 genuala I and lacking genuala II 
and III, but differs in having both sub- 
terminala and parasubterminala I. 
Carebareia phnstoni, n. sp. 
Fig. 5 
Type data.— Holotype and 5 paratypes 
from Venezuela, Falcon, W of Coro, ex 
Marmosa robinsoni (RML 53544), 
25.VII.1968. 
Diagnosis.— Palpal setal formula 
B/B/BBB/4B; palpal claw 3-pronged; ga- 
leala N; chela with tricuspid cap; eyes 2/2; 
1 genuala I; tibiala III; subterminala and 
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GREAT BASIN NATURALIST 
Vol. 37, No. 4 
parasubterminala I; 54 slightly expanded 
dorsal body setae; capitate sensilla; PW/SD 
= 2.10-2.30. 
Description of species.— Larvae. Idiosoma: 
Measuring 315 x 220 in partially engorged 
specimen. Eyes 2/2, anterior larger, on ocu- 
lar plate. Two pairs of humeral setae, 
slightly expanded, measuring 26-29; 54 
slightly expanded dorsal body setae, measur- 
ing 20-22, arranged 8-8-8-6-8-6-6-4; 2 pairs 
of sternal setae, 28-30; 22 preanal setae, 20- 
22; 20 postanal setae, similar in form to 
dorsal body setae, 23; total body setae 104. 
Gnathosoma: Palpal setal formula 
B/B/BBB/4B; palpal claw 3-pronged; chela 
(25) with tricuspid cap; galeala N; gnatho- 
base lightly pimctate, bearing a pair of 
branched setae. Scutum: Sparsely punctate; 
anterior margin shallowly biconcave, poste- 
rior margin biconvex; AM base in line with 
AL bases; SB slightly anterior to PL bases; 
PL>AM>AL; sensilla capitate, head with 
Fig. 5. Larva of Carebareia johnstoni: (a) scutum; (b) leg I distal 3 segments showing specialized setae (mea- 
surements in micrometers) and bases of branched setae; (c) leg II, as above; (d) leg III, as above. 
Dec. 1977 
GOFF, BRENNAN: VENEZUELAN MITES 
509 
coarse setules; PW/SD = 2.10-2.30. Scutal 
measurements: AW 45 (45, 40-50); PW 55 
(59, 55-60); SB 10 (15, 10-16); ASB 16 (17, 
16-20); PSB 10 (11, 10-12); AP 18 (20, 18- 
23); AM 26 (27, 26-29); AL 23 (22, 20-24); 
PL 30 (33, 30-35); sens. 23 x 15 (26 x 15, 
23-28 X 15). Legs: All 7-segmented, termi- 
nating in a pair of claws and a clawlike 
empodium. Onychotrictes absent. IP = 559- 
604. Leg L 192-204; coxa with 1 branched 
seta (IB); trochanter IB; basifemur IB; te- 
lofemur 5B; genu 4B, genuala, micro- 
genuala; tibia 8B, 2 tibialae, microtibiala; 
tarsus (47 x 18) 15B; tarsala (10-11), micro- 
tarsala, subterminala, parasubterminala, pre- 
tarsala. Leg U: 170-190; coxa IB; trochanter 
IB; basifemur 2B; telofemur 4B; genu 3B; 
tibia 6B, 2 tibialae; tarsus (38 x l6) 15B, 
tarsala (13), microtarsala, pretarsala. Leg IIL 
197-210; coxa IB; trochanter IB; basifemur 
2B; telofemur 3B; genu 3B; tibia 6B, tibiala; 
tarsus (52 x 14) 14B. 
Remarks.— This species is named in honor 
of Dr. Donald E. Johnston, Acarology Labo- 
ratory, Ohio State University, in recognition 
of his many significant contributions to 
acarology. 
Literature Cited 
Brennan, J. M. 1970. Two new genera and a new spe- 
cies of Neotropical chiggers (Acarina: Trombicu- 
lidae). Ann. Entomol. Soc. Am. 63: 1694-1696. 
Brennan, J. M. and J. T. Reed. 1975. A list of Vene- 
zuela chiggers, particularly of small mammalian 
hosts (Acarina: Trombiculidae). Brigham Young 
Univ. Sci. Bull., Biol. Series 20(1-2): 45-75.