Systematic analysis of Acanthococcus species (Homoptera: Coccoidea; Eriococcidae) infesting Atriplex in Western North America

23 Pages·1991·10.6 MB·

by  D R Miller

PROC. ENTOMOL. SOC. WASH.
93(2), 1991, pp. 333-355
SYSTEMATIC ANALYSIS OF ACANTHOCOCCUS SPECIES
(HOMOPTERA: COCCOIDEA; ERIOCOCCIDAE) INFESTING
ATRIPLEX IN WESTERN NORTH AMERICA
Douglass R. Miller
Systematic Entomology Laboratory, Agricultural Research Service, U.S. Department
ofAgriculture, Beltsville, MD, USA 20705.
Abstract. —Salt bush {Atriplex spp.) (Chenopodiaceae) is an important source offorage
for livestock at critical times of the year. Salt bush species are declining and suffering
dieoff over extensive areas in the Great Basin and on the Colorado Plateau of western
North America (Nelson et al. in press). Surveys of potential insect pests of several salt
bush species have been conducted and several members ofthe scale insect genus Acan-
thococcus (= Eriococcus) have been discovered. The purpose ofthis paper is to provide
systematic information on the Acanthococcus species that occur on Atriplex to assist
ongoing research on dieoffproblems. Included are seven species ofwhich three are new
and four are redescribed.
Key Words: Scale insect, eriococcid, saltbush
In the United States, the genus Acantho- larged setae there may be some confusion.
coccushasbeentreatedasajuniorsynonym There generally are two distinct sizes ofen-
oiEriococcus. However, the occurrence of larged setae, i.e. large-sized enlarged setae
distinctiveenlargedtubularductsonthetype and small-sized enlarged setae. Unfortu-
species o{Eriococcus {Coccus buxi Fonsco- nately, these sizes are relative within a spe-
lombe) which are present on other species cies; noconsistentsizecriterioncanbe used
from Australia and Europe and are absent to decide whether a seta is large sized or
from the type species of Acanthococcus small sized among all species. However, in
{Acanthococcus aceris Signoret) and most
nearly all cases these relative sizes are dis-
other species from around the world, have tinctandthereshouldbenoconfusionwhen
convinced me that Borchsenius (1948) was
studying a particular species or specimen.
correct when he treated Acanthococcus and Inoneortwocasesaspeciesmayhavesetae
Eriococcusasvalidand separategenera. Be-
thatintergrade from very largeto small, but
cause ofthis change, all ofthe U.S. species
previously treated as members ofEriococ- this circumstance is unusual and is a useful
cus, should now be considered as members characterstate. Legmeasurementsaretaken
ontheoutersurfaceofeach segment. Counts
ofAcanthococcus.
ofenlarged setae include all enlarged setae
Methods on the segment dorsal and ventral. All dor-
Terminology used in this paper follows sal setae are considered to be enlarged even
Miller and McKenzie (1967), Miller and though some may be quite small. Measure-
Gonzales (1975), and Miller (1984). When mentsand numbersaretakenfrom 10 spec-
first reading the terminology for the en- imens when available and are given as a
A
.
334 PROCEEDINGS OFTHE ENTOMOLOGICALSOCIETY OFWASHINGTON
range of numbers followed by the average at dermal orifice; cruciform poresnormally
in parentheses. absent arenosus(Cockerell)
Microtubularducts usuallywith sclerotized
Depositories ofspecimens are as follows:
British Museum (Natural History), London erinntgatdermalorifice;crucifoerrmiopgoorneis(pErehsr-hom)
(BM); California Department of Food and
Agriculture, Sacramento(CDA); University Treatment of Species
ofCalifornia, Davis (UCD); University of Acanthococcus arenosus (Cockerell),
Hawaii, Honolulu (UH); National Museum New Combination
of Natural History, Washington, D.C. Sand eriococcin
(USNM);VirginiaPolytechnicInstituteand
Fig. 1
State University, Blacksburg(VPI); Zoolog-
icalInstitute, AcademyofSciencesofUSSR, Ehococcus arenosusCocktrtW, 1897, 1899,
Leningrad (ZAS). Other abbreviations are: 1900; Femald, 1903; Ferris 1955; Mc-
specimen (spm.), slide (si.), and ad. (adult). Daniel, 1959; Hoy, 1963.
Type material: From the syntypes I have
Acknowledgments chosen and marked as lectotype an adult
am female labeled ""Eriococcus arenosus Ckll.,
forI theigrractreiftuilcitsomstheanfdolcloowmimnegnitndsivoifdutahliss On ?, N. Mex., Cockerell, April 16, 1897
manuscript: C. Riley Nelson, Department Type" (USNM). The slide contains only 1
specimen. In addition, there are 4 paralec-
of Zoology, University of Texas, Austin;
John A. Davidson, Department of Ento- totypes on 2 slides.
Fieldfeatures:Adult femaleelongateoval.
mology, University of Maryland, College
Park; RobertL. SmileyandSueoNakahara, Body varies from gray to light purple. A
Systematic Entomology Laboratory, ARS, smooth, heavy, white ovisac may be inter-
USDA, Beltsville, Maryland. Riley Nel- mixed with grains ofsand.
son's suggestions were especially helpful as This species is found on the spines and
apotentialuseroftheinformationprovided branches ofits host.
Recognition characters: Adult female,
in the publication. mm
mounted, 2.2-3.8 (3.0) long, 1.1-2
mm
Key TO Adult Females of (2.1) wide. Anal lobes lightly sclero-
acanthococcus species that infest tized ventrally; each lobe dorsally with 3
Atriplex enlarged setae (size variable, either lateral
seta equal to posteromedial seta, antero-
1. Five setae on hind tibia 3 medial seta shortest, or all setae equal in
Foursetae on hind tibia 2
2(1). Anal lobes each with 4 enlarged setae .... size), with from 1-5 (3) microtubularducts;
froebeae Miller, n. sp. each lobe ventrally with 3-4 (3) body setae
Anallobeseach with 3 enlarged setae .... and 2-9 (4) sessile pores.
DORSUM
tinsleyi(Cockerell) with enlarged setae of 2 pri-
3(1). Enlargedsetaewith roundorbluntapices . . 4 mary sizes: with 2 largersetae along margin
Enlarged setae with acute apices (Fig. 7) . . of each abdominal segment, also present
whiteheadi Miller, n. sp.
4(3). Fewerthan 65 enlargedsetaeon segment V along thorax and head; remaining setae
includingthose on dorsum and venter ... 5 small. Largest large seta 29-44 (37) /u long,
More than 65 enlarged setae on segment V largest small seta 19-44 (35) n\ on abdom-
includingthose on dorsum and venter . . . inal segments VIII through III longest large
barri Miller, n. sp. seta 1.2-1.7 (1.5) times longer than longest
5(3). Enlarged setae not fusiform in shape 6
Enlarged setae fusiform in shape (sFailga.ri5u)s(.Ferris) tshmoalslesfetrao.mAlnloerntlhaerrgnedasreetaasesslliegnhdtelry,cuarpviecde;s
6(5). Microtubularductswithoutsclerotizedring rounded; those from southern areas robust,
VOLUME 93, NUMBER 2 335
/1\
1 \
I \
w \
\ ''/' \i532s#"
/•V-<>>' 'JS Mi'
Fig. 1. Acanthococcus arenosus (Cockerell). 14 miles W. Phoenix, Arizona, October 15, 1968, on Atriplex sp.
336 PROCEEDINGS OFTHE ENTOMOLOGICALSOCIETY OFWASHINGTON
apicestruncate; allwith thin setalrings. En- gest. Segment 7 with 3 sensory setae; seg-
larged setae ranging from infrequent to ment 6 with 1 noticeably longer than single
abundant—e.g. abdominal segment V with sensory seta on segment 5.
22-55 (37)—large setae showing no longi- Notes: There appear to be two extreme
tudinal pattern. Macrotubular ducts vari- forms of this species, one that occurs in
able in length (4-8 (6) n long), with area northern Oregon, northern Utah, and
farthest from dermal orifice sclerotized and northern and central Nevada, and another
divided into 2 parts, apical portion round- thatoccurs in central andsouthernNevada,
ed, equal or slightly shorter than remaining Arizona, New Mexico, and Texas. The
sclerotizedportion;totalsclerotizedportion northern form is characterized by slender,
unusually short, varying from 0.5-2.0 (1.0) enlarged setae with rounded apices; where-
times length of unsclerotized portion; der- as, the southern form possesses robust, en-
mal orifice with no sclerotized ring. Micro- larged setae with truncate apices. Interme-
tubular ducts scattered over surface. diate forms occur in southern Nevada and
Anal ringeitherdorsal or ventral, with 4, northern Arizona.
rarely 5, pairs ofsetae. This species is similar to Acanthcoccus
VENTERwithlanceolatebodysetaelong eriogoni(Ehrhom),butdiffersinpossessing:
(longest seta on abdominal segment VIII few or no cruciform pores, microtubular
from 32-64(48)nlong,onsegmentIIIfrom ducts without sclerotized ring orifice; A.
53-84 (67) ix), medial setae rarely capitate. eriogoni, on theotherhand, possesses: many
Enlarged setae same as on dorsum, except cruciformpores, microtubularductsusually
more slender, present along margins ofab- with heavily sclerotized ring orifice.
dominal segment VIII through head. Mac- Specimensexamined:ARIZONA, MAR-
rotubularducts of2 sizes: larger size on lat- ICOPA Co.: Phoenix, X-10-1899, on Atri-
eral areas only; smaller size on medial and plex canescens (Chenopodiaceae), T. D. A.
sublateral areas of entire surface, most Cockerell (3 spm. on 2 si.) USNM; 14 mi.
abundant on abdomen. Microtubularducts W. Phoenix, X-15-68, onAtriplexsp., P. F.
restricted to lateral margins only, uncom- Min and Miller(2 ad. femaleon 2 si.)CDA;
mon. Multilocular sessile pores of3 kinds: Tempe, butte, VIII-(?)-18, on Atriplex sp.,
septeloculars rarely present; quinquelocu- G. F. Ferris (1 ad. female) UCD.
lars abundant on posterior margins of ab- NEVADA, LYON Co: Weeks, VII-5-68,
dominal segment, rare on anterior margins onAtriplexsp., D. R. Millerand R. F. Den-
of abdomen, thorax, and head; triloculars no (5 ad. female on 2 si.) UCD. NYE Co.:
most abundant on thorax and head, also Tonopah, VII-6-62, on (?), collector (?) (6
present on anterior margins of abdomen. ad. female on 3 si.) CDA. WASHOE Co.:
Cruciform pores usually absent, rarely with Nixon, VI-24-64, on Bassia hyssopifolia
a few near lateral margins of anterior ab- (Chenopodiaceae), J. A. Froebe (1 ad. fe-
dominal segments, thorax, and head. male) UCD; near Reno, VII-2-47, on Atri-
Legs: hind coxae dorsally with 4-35 (15) plex sp., G. F. Ferris (4 ad. female) UCD.
pores, ventral surface with 0-25 (10); hind WHITEPINECo.: 3 mi. N. McGillonAtri-
femora dorsall> with 0-7 (3) pores, ventral plex sp., D. R. Miller and R. F. Denno (1
surface with 0-2 (1); tibiae with 5 setae; ad. female) UCD; 6 mi. NE. McGill, on
inner, apical, tibial setae robust on hind 2 Atriplex sp., D. R. Miller and R. F. Denno
pairsoflegs, lanceolate on front pairoflegs; (1 ad. female) UCD.
hind tarsi usually slightly longerthan tibiae NEW MEXICO, DONA ANA Co.: Las
(hind tibia/tarsus ratio 0.89-1.06 (0.95)); Cruces, date (?), on A. canescens, "M. and
claws with denticle near tip. Antennae F." (1 spm.) USNM; VIII-4-66, onAtriplex
7-segmented, third or fourth segment lon- sp., D. R.Miller(3ad. femaleon2si.)UCD;
1
VOLUME 93, NUMBER 2 337
Mesilla Park, VIII-(?)-1898, on A. canes- female is heavily coated with many short,
cens, T. D. A. Cockerell (3 spm. on 2 si.) squat crystalline rods that give the body a
USNM. RIO ARRIBA Co.: Embundo, IV- white appearance. One rod on lateral mar-
26-1897, on Psoralea micrantha (Legumi- ginofeachabdominalsegmentislongerand
nosae), T. D. A. Cockerell (1 ad. female broader than the others; these rods are
lectotype, 4 ad. female paralectotypes on 2 slightly curved posteriorly. The ovisac is
si.) USNM. noticeablytoughanddifficulttobreakopen.
OREGON, LAKECo.: AlkaliLake, VIII- Thisspeciesoccursonthecrownandroots
4-68, on Gutierrezia sp. (Compositae), D. ofits host.
R. Miller and R. F. Denno (1 ad. female) Recognition characters: Adult female ho-
UCD; 24 mi. E. Christmas Valley, VIII-4- lotype, mounted, 1.9 mmlong, 1.2 mmwide
mm
68, onAtriplex canescens, D. R. Miller and (paratypes 1.5-3.3 (2.3) long, 1.0-2.5
mm
R. F. Denno (4 ad. female on 2 si.) UCD; (1.9) wide). Anal lobes slightly pro-
9 mi. N. Valley Falls, VIII-4-68, on A. ca- truding, rounded, lightly sclerotized; each
nescens, D. R. Miller and R. F. Denno (5 lobe dorsally with 3 enlarged setae (antero-
ad. female on 3 si.) UCD. medialsetalongestandmostslender,lateral
TEXAS, PRESIDIO Co.: Presidio, XI- seta shortest and most robust), with 4 mi-
19-43,onA. canescens, J. H. Russell(4spm.) crotubularducts; each lobe ventrally with 4
USNM; Presidio, IV-29-52, on A. canes- body setae and 4 sessile pores.
cens, J. H. Russell (5 spm.) USNM. DORSUM with enlarged setae of3 sizes:
UTAH, BOX ELDER Co.: 40 mi. SW. 1 larger seta on margin ofeach abdominal
Rosette, VIII-2-67, on Atriplex sp., D. R. segment, also present on lateral margin of
Miller and D. S. Homing (1 ad. female) thorax and head; 1 pair of smaller setae
UCD. KANECo: Kanab,III-28-59,onSar- present on medial area and sublateral areas
cobatus vermiculatus (Chenopodiaceae), G. ofeach abdominal segment; remaining se-
F. Knowlton (4 ad. female) USNM. tae of intermediate size. Largest large seta
Hosts and distribution: Found on Atri- 37 )u long (paratypes 30-38 (35) y), largest
plex, Gutierrezia, Psoralea, andSarcobatus. intermediate seta 28 long (paratypes 25-
a^
Acanthococcus arenosus is the most com- 31 (28)m), largestsmall seta 16 fxlong(para-
monly collected on Atriplex. types 13-16 (15) m); longest large seta 1.3
Distributed in arid areas ofArizona, Ne- timeslongerthanlongestintermediatesized
vada, New Mexico, Oregon, Texas, and seta (paratypes 1.2-1.3 (1.2) times); longest
Utah. largeseta2.3timeslongerthanlongestsmall
seta (paratypes 1.9-2.4 (2.1) times). Large
Acanthococcus barri Miller,
setaeextremelybroad,withtruncateorblunt
New Species
apices; intermediate setae similar except
Barr eriococcin apices more rounded; small setae relatively
Fig. 2. slender, with rounded apices; largerand in-
Type material: Adult female holotype ( termediate setae with setal rings so thin as
specimen on slide) with right label "Erio- toappearfused to main body ofseta; small-
coccus 2 mi. E. Tonopah, Nye Co., NE- er setae with thin, unfused setal rings. En-
VADA
7-VII-1968 Atriplex canenscens D. larged setae abundant—e.g. abdominal seg-
R. Millerand R. F. Denno 1230"; left label ment V with 1 13 (paratypes with 69 to 111
"Eriococcus barri Miller Holotype TYPE" (81))—small setae forming 2 pairs of lon-
(deposited at UCD). In addition there are gitudinal lines (medial, sublateral), large se-
1 16 paratypes. tae forming 1 pairoflongitudinal lines (lat-
Fieldfeatures: The body is white or light eral). Macrotubularducts in small numbers
yellow; legs are yellowish-brown. The adult over surface. Microtubular ducts elongate
338 PROCEEDINGS OFTHE ENTOMOLOGICALSOCIETY OFWASHINGTON
''im
l/'.°//p:3-
/
'I'h
Fig. 2. AcanthococcusbarriMiller, n. sp. 2 milesE. Tonopah, Nevada,July 7, 1968, onAtriplexcanescens.
VOLUME 93, NUMBER 2 339
(13 n long) (paratypes 11-14 (13) ix), with pores normally absent on anal lobes; anal
area farthest from dermal orifice sclerotized ring rarely ventral and with 3 pairs ofsetae;
and undivided; total sclerotized area ap- microtubular duct orifice ring often com-
proximately0.2 length ofunsclerotizedarea; pletelyunsclerotized;enlargedsetaeonven-
dermal orifice sclerotized. Microtubular termaybepresentfromabdominalsegment
ducts in small numbers over surface. VIII through head; antennae rarely 6- or
Anal ring dorsal, with 4 pairs ofsetae. 8-segmented.
VENTER with lanceolate body setae Notes:I takegreatpleasureinnamingthis
elongate (longest seta on abdominal seg- species/I. barriinhonorofW. F. Barr, Uni-
ment VIII 47 fi long (paratypes 34-50 (42) versity of Idaho. He has provided speci-
ix), on segment III 56 ix (paratypes 47-62 mens ofthis unusual species, and has also
(57) fx), medial setae with acute apices. En- contributed many other Coccoidea collec-
larged setae present along lateral margin tions. Hisassistancehascontributedgreatly
from abdominal segment VIII through tho- towardsamorecomprehensiveunderstand-
rax. Macrotubular ducts same as on dor- ing ofthe scale insects ofthe northwestern
sum, scattered oversurface, most abundant United States.
on lateral areas. Microtubular ducts most This species is similar only to A. white-
abundant on lateral areas, also present an- headi Miller. It differs in possessing: differ-
teriorofeach leg. Multilocular sessile pores ently shaped dorsal setae, and a different
in unusually small numbers on thorax, and enlarged setal pattern. For detailed discus-
of3 kinds: septeloculars uncommon, pres- sion see "notes" under A. whiteheadi.
enton posteriorabdominal segments; quin- Specimens examined: IDAHO, CAN-
queloculars most abundant, present over YON Co.: 15 mi. S. Nampa, VI-27-53, on
abdomen and near spiracles; triloculars un- Atriplexconfertifolia (Chenopodiaceae), W.
common, present on anterior abdominal F. Barr (3 ad. female paratypes on 3 si.)
segmentsandspiracles.Cruciformporesab- UCD, CDA; IX-4-62, on Atriplex sp., W.
sent. F. Barr (6 ad. female paratypes on 6 si.)
Legs: hind coxae dorsally with 45 and 43 UCD, VPI. ELMORE Co.: 15 mi. W.
pores(paratypes with 27-58 (43)), ventrally MountainHome, VII-31-58,onAtriplex^^.,
with 9 and 30 (paratypes with 18-48 (31)); W. F. Barr (4 ad. female paratypes on 4 si.)
hind femora dorsally with 6 and 5 (para- BM, UCD, UH; IX-3-62, on Atriplex sp.,
types with 1-7 (5)), ventrally with and 2 W. F. Barr (4 ad. female paratypes on 3 si.)
(paratypes with 1-6 (4)); tibiae each with 5 UCD, ZAS. OWYHEE Co.: 5 mi. N. Mur-
setae; inner, apical, tibial setae unenlarged; phy, VII-25-56, on Atriplex sp., W. F. Barr
tarsi slightly longer than tibiae (hind tibia/ (2 ad. female paratypes on 2 si.) UCD.
tarsus ratio 0.88) (paratypes 0.82-0.98 NEVADA, ESMERALDA Co.: 6 mi. W.
(0.87)); claws with large denticle. Antennae Tonopah, VII-6-68, on A. canescens, D. P..
7-segmented, fourth segment longest. Seg- Miller and R. F. Denno (7 ad. female para-
ment 7 with 3 sensorysetae; segment6 with types on 5 si.) UCD, USNM. NYE Co.: 2
1 longer and more slender than single sen- mi. E. Tonopah, VII-7-68, onA. canescens,
sory seta on segment 5. D. R. Miller and R. F. Denno (1 ad. female
Variation: Some ofparatypes vary from holotype, 32 ad. female paratypes, 26 first
holotype in possessing the following char- instar nymph paratypes, 19 ad. male para-
acteristics: clusterof6 or7 small sized setae types, 1 third instarmale paratype, 1 fourth
on dorsum ofabdominal segment VIII; an- instarmaleparatypeon 22 si.)UCD; 28 mi.
teromedial seta on anal lobes may be unen- NE. Warm Springs, VII-7-68, onA. canes-
larged, appearing as a body seta; 1-4 mi- cens, D. R. Miller and R. F. Denno (4 ad.
crotubular ducts on each anal lobe; sessile female paratypes on 2 si.) UCD.
340 PROCEEDINGS OFTHE ENTOMOLOGICAL SOCIETY OFWASHINGTON
Host and distribution: Found only on longest lateral setae, including large type,
Atriplex. straight, with apices rounded, slightly more
Probably occurring throughout much of acute than apices of medial seta; medial
the Great Basin. sublateral setae conspicuously curve, with
apicesrounded; allwiththin setal rings. En-
Acanthococcus eriogoni (Ehrhorn), larged setae abundant—e.g. abdominal seg-
New Combination ment V with 27-55 (43)—these setae nor-
Eriogonum eriococcin mally showing no longitudinal pattern;
Fig. 3 although rarely there may be weak indica-
Eriococcus sidae Ferris, 1955; Hoy, 1963; tion of 3 pairs of longitudinal lines, these
suggestedbyslightlylargersetae,whenpres-
McDaniel, 1964.
ent, these lines not visible anterior of ab-
Eriococcus sidae Ferris, 1955; Hoy, 1963;
dominal segment V. Macrotubular ducts
McDaniel, 1964.
densely scattered over dorsum. Microtu-
Type material: From the syntypes I have bular ducts moderate in length 6-8 (7) ii
chosen and marked as lectotype an adult long, with area farthest from dermal orifice
female labeled "Eriococcus eriogoni on Er- sclerotizedand weakly divided into 2 parts,
iogonum, FlagstaffArizonaType" (USNM). apical portion rounded, from 0.5-1.0 (0.8)
Thereare8 specimensontheslide;thespec- times length ofremaining sclerotized por-
imenhorizontallyontherightandvertically tion; total sclerotized area varying from 1-
in the middle is the lectotype. In addition, 5 (2) times longer than unsclerotized area;
there are 7 paralectotypes. dermal orifice varying from heavily scler-
I have examined part ofthe type series of otized to totally unsclerotized. Microtubu-
E. sidae. lar ducts abundant over surface.
Fieldfeatures: Adult female oval. Newly Anal ring ventral, rarely dorsal, with 3,
formed adult females vary from gray to normally 4, pairs ofsetae.
green; becoming red with age. Crystalline VENTER with lanceolate body setae
rods numerous over entire dorsum giving moderate in length (longest seta on abdom-
eriococcin a wooly appearance. inal segment VIII from 39-50 (45) )u long,
Present on roots and subterranean or ae- on segment III from 47-62 (55) m), medial
rial crown ofhosts. setae stout, capitate. Enlarged setae nor-
Recognition characters: Adult female, mally of small size, straight; present near
mm
mounted, 1.7-2.5 (2.2) long, 0.9-1.8 body margin from abdominal segment VIII
mm
(1.2) wide. Anal lobes apically acute, through head. Macrotubular ducts of 2
moderately sclerotized; each lobe dorsally kinds: largersize present on lateral and sub-
with 3enlargedsetae(lateralsetaeitherequal lateral areas; smaller size normally only
toorlargerthanposteromedial seta, antero- slightly smaller than large size, present in
medial seta shortest), with 0-3 (2) micro- medialareasfromsegmentVIIorVIthrough
tubular ducts; each lobe ventrally with 3, head. Microtubular ducts present over en-
rarely 4, slenderbody setae and 2-9 (5) ses- tire surface, most abundant near lateral
sile pores. margins. Multilocular sessile pores of 3
DORSUM
with enlarged setae of 2 pri- kinds: septeloculars least common, ifpres-
mary sizes: 1 seta on margin of each ab- ent, usually on abdominal segment IX or
dominal segment and several on marginsof VIII; quinqueloculars mostabundant, pres-
thorax and abdomen large; remaining setae ent over entire surface; triloculars present
conspicuouslysmaller. Largestlargeseta41- onanteriorabdominalsegments,thorax,and
67 (54) II long, largest small seta 33-50 (40) head. Cruciform pores present along lateral
n\ on abdominal segments VIII through III margin ofanterior abdominal segments, on
VOLUME NUMBER
93, 2 341
Fig. 3. Acanthococcuseriogoni(Ehrhom). Flagstaff, Arizona, date and host unknown.
342 PROCEEDINGS OFTHE ENTOMOLOGICALSOCIETYOFWASHINGTON
lateral areas ofthorax and head, and ante- O. E. Bremner (4 ad. female of4 si.) CDA,
rior ofeach leg. UCD; on Eriogonum sp. (Polygonaceae),
Legs: hindcoxaedorsallywith 17-45 (27) collector (?) (1 lectotype ad. female and 7
pores, ventral surface with 4-20 (12); hind paralectotypeson 1 si.)USNM; IX-(?)-1900,
femoradorsallywith 3-14 (8) pores, ventral on Eriogonum sp., O. E. Bremner (5 ad.
surface with 0-5 (2); tibiae with 5 setae; female on 4 si.) UCD; Yuba City, on Hap-
inner, apical, tibial setaerobust; tarsi longer lopappusacradenius(?)(Compositae), H. L.
thantibiae (hindtibia/tarsusratio 0.78-0.93 McKenzie (4 ad. female on 3 si.) UCD.
MARICOPA
(0.88)); claws with denticle neartip. Anten- Co.: quarantined at Phoenix
nae 6-segmented, rarely with third segment from Alamo, Texas, 1-21-69, on Echinopsis
dividedformingseventhsegment,thirdseg- sp. (Cactaceae), P. F. Min and Hancock (2
ment longest. Apical segment with 2 or 3 ad. female on 2 si.) UCD, CDA; 5 mi. E.
sensory setae; second segment from apex Phoenix, IX-3-68, on(?)(Chenopodiaceae),
with sensory setae absent; third segment D. R. Miller and J. E. Lauck (2 ad. female)
from apex with only 1 which is short and UCD. PIMA Co.: 35 mi. S. Tucson, Santa
robust. Rita Range, on Eriogonum wrightii, H. S.
Notes: This is an extremely variable spe- Haskell (17 ad. female, 7 second instar fe-
cies. I believed for some time that it was a male, 65 first instars, 3 second instar male
synonym of/I. dubius, butaftercareful con- on 6 si.) UCD.
sideration, I have concluded that they are CALIFORNIA, IMPERIAL Co.: 1 mi.
distinct. Because ofthe extreme variability W. Glamis, 1-28-65, on Eriogonum sp., D.
within these species, it is not possible to use R. Miller (2 ad. female on 2 si.) UCD; 12
one character to separate them, instead, it mi. E. Holtville, XII-1 1-58,onEphedracal-
is necessary to use a combination ofchar- ifornica(Ephedraceae),G. L. Osbom(12ad.
acters. Acanthococcus eriogoni possesses: female, 5 second instarfemale, 3 firstinstar,
enlargedsetaewithroundedapices; strongly 1 ad. male, 1 fourth instar male, 3 second
curved medial and sublateral setae; medial instar male on 7 si.) CDA, UCD; Imperial,
andsublateralsetaeallofapproximatelythe XII-28-63, on "cactus," L. Phipps and G.
same size, particularly on abdominal seg- Skaggs (3 ad. female on 3 si.) CDA. LOS
ment V forward through head; front tibiae ANGELES Co.: Lancaster, VI-12-18, on
with 5 setae; and microtubular ducts with Haplopappus (= Isocoma) venetus, G. F.
longareaofsclerotization; A. dubius, on the Ferris (6 ad. female on 2 si.) UCD. RIV-
other hand, possesses: enlarged setae with ERSIDECo.: 18 mi. W. Blythe, 1-29-65, on
acute apices; straight or slightly curved me- Palafoxia linearis (Compositae) and Atri-
dial and sublateral setae; medial and sub- plex sp. (Chenopodiceae), D. R. Miller (4
lateral setae of2 sizes, large size forming 3 ad. female on 4 si.) UCD; 4 mi. W. Desert
pairs oflongitudinal lines from abdominal Center, 11-20-58, "in soil," E. I. Schlinger
segmentVIII throughposteriorthorax; front (3 ad. female) UCD; Desert Center, IV-18-
tibiae normally with 6 setae; and microtu- 66, on Euphorbia sp. (Euphorbiaceae), R. J.
bularductsnormallywith shortareaofscle- Gill and L. L. Johnson (1 ad. female) CDA;
rotization. X-5-66, on Eriogonum deflexum, D. Fis-
See "notes" underE. arenosus for an ad- kaali (1 ad. female, 3 second instar female,
ditional comparison. 3 second instar male on 6 si.) CDA. SAN
Specimens examined: ARIZONA, CO- BERNARDINOCo.: 5 mi. S. KramerJunc-
CHISE Co.: 21 mi. N. Bisbee, VIII-2-66, tion, XII-28-64, 1-24-65,on CeratoidesJan-
on (?), D. R. Miller (1 ad. female) UCD. ata(Chenopodiaceae),D. R.andJ. F. Miller
COCONINO Co.: Flagstaff, date (?), on (?), (3 ad. female on 2 si.) UCD. SAN DIEGO