F. G. Werner.
Additions to Epicauta, with New Synonymy and a Change of Names (Coleoptera: Meloidae).
Psyche 56(3):93-111, 1949.

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PSYCHE
VOL. 56 SEPTEMBER, 1949 No. 3
ADDITIONS TO EPICAUTA, WITH NEW
SYNONYMY AND A CHANGE OF NAMES
(COLEOPTERA : MELOIDB)
Biological Laboratories, Harvard University The numerous specimens of Epicauta which have been made available to the author in the past two years have included several new species from the United States and Lower California as well as specimens which indicate that some of the former conclusions regarding our species were erroneous.
The most important changes are in-
cluded in this paper.
The author owesa debt of gratitude
to the curators of almost all the major museums in North America for their generosity and especially to Mr. Frank H. Parker and Mr. G. P. Mackenzie, who have been most free with specimens from their private collections and with information of real value in understanding the limits of some of our species.
The arrangement followed is that of my former paper on the genus, and changes that will have to be made in the key to species and in descriptions will be noted in their proper places under the species concerned. Epicauta tenebrosa sp. n.
Epicauta pedalis, Horn, 1873, Proc. Am. Phil. Soc. 13: 99 (in part). Werner, 1945, Bull. M. C. Z. 45: 440 (in part). Arizona specimens which have been assigned to Epi- cauta pedalis Lee. should be referred to this species. The 1 Published with a grant from the Museum of Comparative Zoology at Harvard College.
93
Pu&f 56:93-111 t 1949). hvY/psyche mtclub ore/56/5&093 hlml



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Psyche
[Sept.
California Academy series of pedalis from Lower Cali- fornia, the type locality, shows that there is a constant difference between the Lower California and Arizona specimens. From pedalis, tenebrosa can be distinguished in either sex by the lack of a pale sutural margin on the elytra and by its smaller size. The males have much more slender antennas and have the tip of the asdeagus of a different shape. (Fig. 1.)
c .
Fig. 1.
A. Antenna of Epicauta pedalis Lee., male. B. Antenna of Epicauta tenebrosa sp. n., male.
C. Tip of sedeagus of Epicauta pedalis,
male.
D. Tip of sedeagus of Epicauta tenebrosa, male. Length : 8 to 10 mm. Black, moderately densely clothed with decumbent pubescence, which is tan on the elytra, paler on the head and pronotum and cinereous on the underside. Legs pale brown. Head subquadrate, with moderately dense and deep punctures, distinctly microre- ticulate on the intervals. Suture very distinctly im- pressed. Antenna1 calluses small, denuded, shiny. Eyes prominent, transverse, slightly wider than in pedalis. Antenni~ in both sexes quite slender, tapering, reaching almost to the middle of the elytra, two and four-fifths times as long as an anterior tibia. First segment slightly thickened, reaching halfway across the eye ; second short, three-sevenths as long as the first; third slightly longer than first; fourth four-fifths as long as third; succeeding segments decreasing slightly in length and width. The



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19491 Werner-Epicad a 95
third and following segments are just perceptibly flat- tened, especially in the male.
Pronotum as broad as long, subquadrate, with the sides parallel for the basal three-fourths, then converging at a forty-five degree angle, with the anterior angles rounded. Surface like that of head. Midline distinctly impressed and narrowly denuded. Basal impressed line distinct but not denuded. Elytra with a narrow denuded zone across the base, where normally covered by the base of the prono- turn. Tips of femora and tibiae and all of tarsi, except for a few hairs at the base of the basal segments, with dark brown pubescence. Anterior tibiae of male with a single stout, slightly incurved spur. Posterior tibia1 spurs slightly broadened and flattened, the outer broader and longer.
Holotype : 3, Tucson, Arizona VII-30 (Fall Coll. M.C.Z. No. 28221)
Allotype: 9, topotypical, VIII-1 (Fall Coll.) Paratypes : Tucson. A rizona : I$ VII-21 (Fall Coll.) , I$ VII-21 (Liebeck Coll.), 632, 699 Aug. 1935 Bryant (Parker). Sabino Canyon, Santa Catalina Mts., Ari- zona: 19 7-14-32 E. D. Ball (Parker), 13, 19 7-12-32 R. H. Beamer (U. Kansas), 13 VII-26-1948 F. Werner & W. Nutting, at light (Werner).
Tenebrosa runs to couplet 63 in my key.
It can be dis-
tinguished from pedalis by the characters mentioned above and from balli by the normal mandibles and the presence of a single spur on the anterior tibiae in the male. Epicauta bispinosa sp. n.
This is the third species to be discovered in the United States belonging to a very closely-knit group, composed of E. rnaculata (Say), normalis Werner and bispinosa sp. n. These all have the same color, form and markings and the females cannot be distinguished except by association with males. All have numerous denuded spots over the whole body and elytra and have the elytra covering the abdomen almost completely and not conspicuously bulg- ing. The male of muculata has the last segment of the labial palpi expanded and suborbicular in outline and the



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96 Psyche [ Sept.
second segment also expanded, one short, incurved spur on the anterior tibiae and the first segment of the anterior tarsi padded almost to the base. The male of normalis differs from it in having unexpanded palpi and in having the pad confined to the apical third of the first anterior tarsal segment but is like it in having a single anterior tibia1 spur. The male of bkpinosa has two slender spurs on the anterior tibiae as in the females of all three, has un- expanded palpi and the pad of the first anterior tarsal segment as in maculata. This combination of characters in the males is exactly like that of the female of any of the three species and it is only by the genitalia that the male can be distinguished from the females at all. Length : 9 to 12 mm. Black, quite densely clothed with pale olive-cinereous to cinereous pubescence, with scat- tered denuded spots as in maculata (Say). Indistin- wuishable from maculata and normalis in shape, propor- a.
tions and sculpture of head and pronotum. Antenn~e
almost identical with those of maculata, which vary slightly in different sized specimens.
Holotype: <? 10 mi. E. of Sonoita, Sta. Cruz Co., Ari- zona, alt. 4800 ft., in grassland, Aug. 1, 1948. F. Werner,
E. & V. Nntting. Feeding on leaves of Chamcesaracha coronopus (Dunal) A. Gray. (M.C.Z. No. 28219) Allotype : eutopotypical (M.C.Z.)
Paratypes: 62,#, 9?? eutopotypical, in U.S.N.M., Chicago Nat. Hist. Mus., U. Kansas., Cal. Acad., collec- tions of F. H. Parker, G. P. Mackenzie and F. Werner. In an area less than one hundred miles square in south- eastern Arizona there occur no less than four distinct, apparently very closely related species in the maculata group (maculata, normalis, bispinosa and nogales) . One would expect that if these species were interfertile a fair number of hybrid forms would occur. There has been no attempt made to cross one with another experimentally but so far no morphological evidence of hybridization has come under observation. It is within the realm of pos- sibility that hybrids do occur, at least among the first three species, since there is no difference in habitus, all varying greatly in the size and number of denuded spots



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and in body size so that unusual specimens might be overlooked in the field.
When one examines the distribution of the four species in Arizona, a region well-known for its diversity of habitat and life zones, he gets some clue as to the possible reasons for segregation. E. rnaculata, ranging across the Great Plains and even as far east as Ohio, extends its range westward south of the Rockies onto the Colorado Plateau, just north of the Arizona White Mts., where it is quite abundant, feeding on the leaves of a species of Amaran- thus and Salsola. It also reaches the plateau to the north of the Huachuca Mts., where it is likewise abundant and feeds on the same or similar plants. 011 this plateau and nearby it is taken occasionally on Solatiurn, elceagni- folium. The specimens on this plant tend toward smaller spots and more luteous pubescence than most populations and may represent a separate race. A series collected by Mr. Parker at Phoenix was feeding on Kallstramia. It does not seem to differ from normal specimens from other parts of the range.
The record of E. normalis is not as complete. It is found from the Rockies to the Sierras and seems to range farther north than maculata. It has been taken in the Chiricahua and Huachuca Mts. and at Willcox. No food plant records had been kept for these specimens. The '
Willcox series was mixed with maculata but no attempt had been made to segregate by food plant or exact locality. It seems possible that normalis usually is found at higher altitudes than its near relatives. Extensive collecting on the plateau in 1948 did not produce any specimens. E. nogales has turned up only in or near the Santa Cruz river valley and it is quite evident that it must have a more extended range in the adjacent part of Mexico. The other species have not been taken in this valley. The occurrence of the fourth species, E. bispinosa, on the plateau north of the Huachuca Mts. in an area where E. maculata also occurs abundantly, would be quite in- explicable were it not for some observations made at the time it was taken. Both species were abundant at a road- side stop 10 miles east of Sonoita. Maculata was feeding



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98 Psyche [Sept.
on Amaranthus and Salsola, in considerable numbers. Under these plants were scattered patches of Chawsa- racha, a low solanaceous plant, which had bispinosa feed- ing on them. The species, as mentioned before, differ only in the male secondary sexual characters and several specimens were collected from both hosts before the dif- ferences were discovered. Then careful collecting by host plant revealed that out of 87 maculata and 63 bispinosa males not a single one was on the wrong plant. It can be safely surmised that the females show the same selection. The question of expressing the known relationships in the taxonomy of the group is one to which the author has given considerable thought and which he has discussed with his colleagues in some detail. Dr. George Horn would probably have left at least the three very similar species as one, readily identifiable, species. This ap- proach is particularly attractive to one who attempts to determine numerous museum specimens but is becoming increasingly indefensible as we attempt to apply the taxonomist's results to problems in the field. Assuming that we attach names to all three forms, we still have at least two possible techniques, each with some merit. Using the extreme similarity of the three as a criterion, we can place them all in one species, with the topical and two other subspecies, with supposed geo- ~aphical replacement. This view would be strengthened P
if bispinosa were found to have a wide range in northern Mexico and maculata not. It serves to point out the ex- tremely great similarity of the three. It is weakened by the lack of evidence that the three hybridize where they meet, as in southeastern Arizona. We expect subspecies to be populations which have differentiated slightly be- hind barriers but which have not gone so far in differentia- tion that they cannot interbreed wherever they come to- gether geographically.
The alternative method, and the one which the pr.esent author favors, is to call each a species. From the avail- able evidence we have three geographically isolated species which show no tendency to interbreed. Where the ranges of maculata and normalis meet, along the front of



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1.9491 Werner-Epicaut a 99
the Rockies, an altitudinal segregation acts and the same mechanism may act in Arizona where the ranges overlap. Where maculata and bispinosa overlap, or where one has differentiated from the other as the case may be, strict adherence to host plant specificity serves to segregate the two in the adult stage and present a barrier to inter- breeding.
Present-day conditions in Arizona are exceedingly favorable for study of host specificity of Epicauta. A good proportion of the land is heavily grazed, the only comparatively untouched parts of many areas being along the main roads where the vegetation is protected by fences. Any adults of the herb-feeding species that emerge congregate on the roadside plants. A fairly high percentage of the individuals in the area must assemble here. Being parasitic and living in an area of uncertain rainfall, the number of individuals varies greatly from year to year. When a patch is found which supports blister beetles it usually has several species within a small area. Under such conditions one would expect any pos- sible hybridization to occur. "When none does occur, it is certainly an indication that there is some barrier, be it intersterility, micro-ecological isolation on host plants or even psychological.
Therefore the author maintains that the occurrence of maculata and bispinosa side by side on different food plants is a clear indication that they are distinct popula- tions and since no intergrades have been found to indicate hybridization, prefers to treat them as species. At the same time, he feels certain that as more becomes known about both, this food plant isolation will be found not to be the primary factor in keeping the two separate. Epicauta cinerea (Forst.)
Meloe cinereus Forster, 1771, Cat. Animals N. Am. : 62. Lytta fissilab~is LeConte, 1850, Agassiz Lake Superior 4: 232; 1853, Proc. Acad. Nat. Sci. Phila. 6: 339. (new synonymy)
Epicauta fissildbris, Horn, 1873, Proc. Am. Phil. Soc. 13 : 102. Werner, 1945, Bull. M.C.Z. 45: 456.



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100 Psyche [Sept.
LeConte described fissilabris from Lake Superior and Hudson's Bay Territory and since the time of its descrip- tion very few specimens have been taken. These, how- ever, show that there is a close relationship between it and cinerea. The author was unable to distinguish between the two species at the time he wrote his revision of the genus, except on the basis of color. Subsequent speci- mens indicate from their distribution that fissilabris is a marginal form of cinerea. It has been taken at Aweme, Manitoba ; Tokio, North Dakota ; Hope, Arkansas and Smithville and Stillwater, Oklahoma. These localities coincide fairly well with the northern and western limits '
of cinerea. ' The Arkansas and Oklahoma specimens were taken in company with normal cinerea.
Epicauta pestif era nomen novum
Epicauta rnarginata auct., nec Fabricius (in part). Epicauta cinerea auct., nec Forster (in part). Qicauta solani Werner, 1945, Bull. M.C.Z. 45: 457, nee Epicauta KoeMeri var. solani Denier, 1940, Rev. de la Soc. Ent. Argentina 10: 421.
It is hoped that at last our common margined blister beetle has a name that will stick with it. Epicauta ficta sp. n.
This unicolorous grey species is most closely allied in our fauna to cinema (Forst.), having similar antenna but broad posterior tibial spurs. It differs from grey speci- mens of pestifera in its short, stout antennee and from brunnea Werner by the broad posterior tibial spurs and unexpanded anterior tarsi in the male. It seems to be most clos4-y related to Epicauta obesa from Vera Cruz on the Caribbean coast of Mexico.
Length: 9 to 12 mrn. Black, densely clothed with de- cumbe-it cinereous to yellowish-cinereous pubescence. A~tenrse short but of a form similar to those of cinerea. Head subtriangular. Surface microreticulate, densely ard rather d~eply punctured. Midline very feebly im- pressed, usually not visible under low magnification. Antenna1 calluses small, slightly raised, denuded and



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shallowly mieroreticulate. Eyes rather small, transverse, narrow, barely extending inwardly beyond the antenna1 sockets. Antennas short, extending to just beyond the base of the elytra, twice as long as an anterior tibia. In the male the first segment is stout, the heaviest segment, reaching one-third across the eye; second slender, seven- tenths as long as first; third one-sixth longer than first, increasing gradually in thickness toward the apex where it is one and six-tenths times as wide as at the base. First two segments and base of third with cinereous pubescence. Fourth segment three-fifths as long as third; fifth and sixth equal to fourth in length, the apices of the third, fourth and fifth equal in thickness, wider than their bases. The length decreases gradually from the sixth to the tenth, which is five-sixths as long as the sixth. The sixth to the tenth are individually almost uniform in thickness. Last segment one and one-half times as long as tenth. The proportions are the same in the female except that the first and intermediate segments are not enlarged. Pro- notmn subquadrate, slightly longer than. broad. Midline not impressed or denuded.
Elytra narrowly denuded and with a little black pubes- cence at the base where covered by the base of the prono- tnm. Outer margin of anterior tibk and top of anterior tarsi of male slightly denuded, the first tarsal segment slightly thickened. Posterior tibia1 spurs broadened, the outer slightly the broader and longer. In some of the males there is a small spot of black pubescence on the hind margin of the abdominal stern1 tes and a mid-dorsal black line on the pygidium. This character is present in obesa and several other species in southern Mexico. Holotype: d' Broken Bow, McCurtain Go., Oklahoma Aug. 27, 1931 M. L. Costner (M.C.Z. No. 28223). Allotype: $ Smithville, Payne Co., Oki. Aug. 24, 1931 W. D. Davis (M.C.Z.).
Paratypes : Oklahoma : 3Jy eutopotypical ; 3JJ Broken Bow Aug. 29, 1931 M. L. Costlier; 1% Broken Bow AMS. 26, 1931 W. D. Davis; Id, 3?? Smithville Aug. 24, 1931 W. I?. Davis; W<? Idabel July 27, 1931 A. 0. Elrod; I? Stillwater Sept. 3, 1931 E. Hison ; 18 Stillwater Sept. 14,



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102 Psyche [ Sept.
1930 E. Hixon; I? Stillwater Sept. 15,1930 E. Hixon; 18 Stillwater Oct. 1,1930 V. Laird; I? Jay Jul. 5,1931 M. L. Costner.
Paratypes deposited in the collections of the U.S.N.M., Cornell U., U. of Oklahoma and F. Werner. Males with midventral spots on the abdominal sternites run to couplet 37 in the key but can be separated by the absence of scutellar and humeral spots on the elytra. The rest key to solani (pestifera) and can be separated by the short, heavy antennae.
Epicauta senilis sp. n.
The combination of shaggy grey pubescence and pair of denuded callosities on the pronotum distinguish this species from all others in our fauna. Champion's candi- data from Mexico has similar characters but has the outer posterior tibial spurs spoonshaped.
Length : 9 mm. Head broadly triangular, quite densely and moderately deeply punctured, with the intervals quite densely punctulate. Median impressed line distinct down to the level of the eyes, bordered by a narrow denuded area. Antenna1 calluses small, low. Eyes large, narrow, excavated next to the antennae. Antennae slender, twice as long as an anterior tibia. First segment slender, reaching three-fourths across the eye ; second half as long as first ; third just shorter than the first. The basal three segments with some short cinereous pubescence behind. Fourth and following segments two-thirds as long as third, gradually decreasing in thickness. Pronoturn quadrat%, cons~icuously bulging on the disc. Median impressed line distinct, supplemented by a narrow de- nuded area. Basal imuressed line distinct. With a pair of smooth, denuded callosities just before the middle, as in callosa. Surface similar to that of head. The pubes- cence on the pronotum is directed irregularly, giving a ragged appearance. Elytra black next to the scutellum and across the base where normally covered by the base of the pronotmn. Anterior legs of male not modified. Anterior tibial spurs of both sexes rather stout, spiniform,



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somewhat incurved. Posterior tibial spurs slender, the outer sticklike, the inner spiniform.
Holotype: (? Luna Co., New Mexico, 4000 ft. July 25, 1939, - Rehn and Rehn (Acad. Nat. Sci. Phila.) Allotype :
Douglas, Arizona, July 23, 1929 W. W.
Jones (Parker)
Paratypes: 18 Dragoon Mts., Arizona IX-1047 D. J. & J. N. Knull (Ohio State) ; U Sierra Blanca, El Paso Co., Texas, Sep. 13-14,1912 (USNM).
This species runs to callosa LeConte in my key but is distinguished by the long, shaggy pubescence of the pro- thorax and back of the head and heavy anterior tibial spurs. It goes to group BB in the table but does not seem to be very closely related to any known species. Epicauta afoveata sp. n.
Length: 7 to 9 mm. Black, sparsely clothed with pale cinereous pubescence. Elytra with inconspicuous scutel- lar and humeral black spot. A member of the caviceps A B
Fig. 2. A. Head of Epicauta afoveata sp. n. B. Head of Epicauta im- pressifrons V.D.
group, apparently most closely related to impressifrons Van Dyke, which it resembles in general appearances, differing mainly in the lack of occipital callosities, lack of a pit at the inner border of the eyes and by certain second- ary sexual characters in the male.
(Fig. 2.)




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104 Psyche [ Sept.
Head subtriangular, without occipital callosities or deeply impressed hind margin.
Surface shiny, feebly
microreticulate, moderately densely and deeply punctured except near the midline on the occiput, on the antenna1 calluses and on a narrow zone behind the eyes. Midline distinctly impressed to just below the upper level of the eyes. A narrow zone in the middle of the head often gla- brous and without punctures, as in Fig. 2A. Antenna1 calluses small but denuded. Eyes oblique, narrow, rounded at the inner margin, bordered behind by a nar- row, smooth, denuded zone one-fourth their greatest width. There is no trace of a pit at the inner edge of this denuded zone. Clypeus and labrum sculptured like rest of head. Antennae almost uniform in thickness, reaching the basal third of the elytra, two and one-half times as long as an anterior tibia. First segment reaching one- third across the eye, moderately slender but nevertheless the thickest segment. There is often some cinereous pu- bescence on the dorsal and posterior surfaces. Second segment two-sevenths as long as first, moderately slen- der; third slender, a little more than twice as long as sec- ond; fourth three-fourths as long as third; the rest de- creasing slightly in length and thickness. Pronotum slightly broader than long, with the sides roughly parallel on the basal two-thirds, then converging at a forty-five degree angle. Surface more deeply punc- tured and microreticulate than that of head. Disc roughened, flattened on the basal two-thirds, with a feeble narrow median smooth area on the basal half. Basal impressed line deep ; median suture absent or present only on the middle of the disc. Pubescence of the disc sparse, directed laterally in part and in a pair of small anterior whorls. Elytra with slightly denser pubescence than the head, with scutellar and humeral black spot, inconspicuous because of the sparseness of the pubescence. Pubescence of the underside denser than above, uniformly pale ciner- eons. Second to sixth abdominal sternites of male broadly denuded, the sixth strongly notched apically. Legs with pale cinereous pubescence except for the tips of the femora, tips of the tibiee and outer edge of mid-



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die tibiae and the tarsi, which are black. The first tar-
sal segments often have a few cinereous hairs dorsally at the base.
Male with two spurs on the anterior tibiae and with posterior surface of trochanter, femur and tibia of mid- dle and hind legs denuded, slightly flattened, with a dor- sal fringe of long cinereous hairs. Posterior tibia1 spurs slender, sticklike.
Holotype: 8 Borrego, San Diego Co., California Oct. 8, 1947 G. P. Mackenzie (M.C.Z. No. 28220) Allot ype : $ eutopotypical (M.C.Z.)
Paratypes: lln, 3$? eutopotypical; 2$$ topotypical Oct. 28, 1939; 18, 19 topotypical Oct. 14, 1948. 583, 68 San Jacinto Mts., Riverside Co., California Oct. 7, 1947. 1<? Vallecitos, San Diego Co., California Oct. 28, 1939. All collected by G. P. Mackenzie.
Paratypes are deposited in the collections of the U. S.N.M., Chicago Nat. Hist. Mus., Calif. Acad., G. P. Mackenzie and F. Werner.
Mr. Mackenzie, who kindly loaned this fine series for description, appends the following information on the localities : Borrego (sometimes spelled Borego), several miles south of the town; San Jacinto Mts., about fifteen miles west of Indio on Rt. 74, on the east slope of the mountains; Vallecitos, 20 miles south of Borrego. El- evation of all three places ca. 2500 ft. Vegetation of a desert type.
In my key the male runs to couplet 37, differing from aspera and migritamis by being black with sparse cin- ereous pubescence and in having the midventral abdom- inal blackmarkings composed of denuded areas with at most scattered, very short pubescence, rather than of black pubescence which is as dense as on the rest of the abdome~i in aspera. The female keys to couplet 67, but differs from iitgrata and lomgicollis in its small size and uniform pubescence. Some females of impressifrons also key out here but can be distinguished by head form. Epicauta impressif rons Van Dyke
1929, Bull. Br. Ent. Soc. 24: 12.
Several samples of Epicauta from near the type lo-



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Psyche
[ Sept.
cality of impressif rons are composed of specimens which seem most closely related to that species but which dif- fer in several characters ordinarily of importance in the group. The variation is continuous enough that all should be included in impressifrons but isolated samples often have a distinctly different aspect. First there is a striking difference in size and more or less correlated with it a difference in pubescence, the larger specimens having it much denser. Also more or less correlated with the denser pubescence is the pres- ence of the midventral, lateral and dorsal black abdom- inal markings and scutellar and humeral spots charac- teristic of the caviceps group to which impressifrons be- longs.
One lot of eight specimens from Whitewater has mid- ventral spots in both males and females. Another se- ries of 25, from Morongo Valley, collected by G. P. Mackenzie, has these spots in the male but not in the female even though some are as large as the Whitewa- ter females. This series has sparser pubescence than the Whitewater lot. Other smaller lots from several localities are similar to the Morongo Valley set. The distribution of the species seems to follow a def- inite northwest-southeast line, from Cajon Pass in San Bernardino Co. to Fish Springs on the Salton Sea. It has been taken most abundantly in the vicinity of Palm Springs in Riverside Co., at Whitewater, Cabazon, Mo- rongo Valley and Indio, all within twenty miles map dis- tance from Palm Springs, in the Coachella Valley. Epicauta occipitalis sp. n.
Length: 8 to 11 mm. Black, densely clothed with yel- low-cinereous to light rufous pubescence, which is dark- er above than below. Disc of pronoturn with dense short, erect pubescence, not denuded anteriorly as in di- versipubescens Mayd. Elytra usually with a small black scutellar spot. Denuded spots on the midline of the abdominal sternites in the male. Middle and hind femora of male flattened behind, denuded and with a margin of long hairs above. Head bulging at the oc- ciput, the bulge not split by a deepened midline.



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19491 Werner-Epicaut a 107
Head suboval, widest just behind the eyes, broadly rounded behind, with the posterior margin straight in front view, excavated when seen from above. Seen in side view, the occiput appears bulged. Surface densely punctured except along the narrowly denuded midline. Antenna1 calluses small, denuded. Median impressed line distinct down to the level of the eyes. Eyes fairly prominent, rather narrow (.47 times as wide as long), transverse. Antennae reaching to the middle of the elytra in the male, two and two-thirds as long as an an- terior tibia, slightly shorter in the female, two and one- half times as long as an anterior tibia, slender, almost uniform in thickness, slightly thicker in the male than in the female. First segment reaching halfway across the eye, the stoutest segment; second .55 times as long as first; third as long as first; fourth and following sub- equal, three-fourths as long as third.
The first three
segments have some pale pubescence.
Pronotum broadly campanulate, slightly longer than broad, densely clothed on the disc with short erect pubescence. This pubescence is composed of short, swollen but pointed hairs which are circular in cross- section. E. wheeleri Horn has similar discal pubes- cence, E. rileyi and å£' rehni similar but much more slen- der. The midline and an oblique area from the anterior angles to the middle somewhat elevated. Elytra with a small scutellar black spot which may be reduced to a few hairs. Abdominal sternites of male with a denuded spot on the midline posteriorly, with only a few short black hairs and setae present on them. Middle and pos- terior trochanters, femora and tibiae of male flattened and broadly denuded behind, fringed above with long pale pubescence. The corresponding edge of the an- terior trochanters and femora also denuded but not fringed with long hairs. Anterior tibial spurs of male slightly shortened, the first tarsal segment a little thick- ened. Posterior tibial spurs slender, sticklike. Tips of femora and tibiae and all but base of tarsi with black pubescence.
Holotype: 3 20 mi. N. of Mesquital, Lower California



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108 Psyche [ Sept.
IX-27-1941 Ross and Bohart (Calif. Acad. No. 6126) Allotype : $ eu-topotypical (Calif. Acad.) Paratypes: 17#, lo?? eutopotypical. 18 El Arco, L. Calif. IX-28-1941.
Paratypes have been placed in the M.C.Z. collection (No. 28222), Chicago Nat. Hist. Mus., collections of F. H. Parker, G. P. Mackenzie and I?. Werner. The localities are in the Vizcaino Desert in the south- ern part of the northern district of Lower California. (See Proc. Calif. Acad. Sci. (4th ser.) 24: 8.) This species belongs to the caviceps group and looks most like diversipdescens Mayd. but differs in its narrower head, bulging occiput and thickened erect hairs on the pronotum. The male keys to couplet 37, aspera but differs in the broadly denuded flattened sur- face of the femora. The female keys to part 2 of couplet 64 (with the addition of "or with a small scutellar spot") and thence to rehni in couplet 75. It differs from ~ehni in lacking the ridges on the head and from uni- forma and alpha by the dense erect pubescence on the pronotal disc.
Epicauta lauta subsp. rossi subsp. nov.
Large series of Epicauta lauta from the United States show very little variation in color. One specimen
from Lower California, the only representative of the species seen from there, shows a striking deviation from the usual uniform coloration. It has the pubescence the same as in lauta but the around color is black, with the elytra tan. It looks more like the female of polingi than lautn but is structurally identical with the latter. Holotype: 3, 15 mi. S. of San Domingo, Lower Cali- fornia, October 4, 1941. Ross and Bohart. (Calif. Acad.
No. 6127).
Epicauta virgulata (Lee.)
Macrobasis virgulat a LeConte, 1866, Smiths. Misc. Coll. 6: no. 167, 2nd ed. : 156.
Epicauta virgulata, Werner, 1945, Bull. M.C.Z. 45: 512 (in part).




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A re-examination of material in this species shows
that two species are present, virgulata being the Lower California species, extending to southwestern Arizona and hirsutipb escens (Mayd.) being found from western Texas to southeastern Arizona.
The description of virgulata in my revision need not be greatly changed except for addition of characters by which it differs from hirsutipuhescens. The shape of the hind trochanters serve to separate it in both sexes (Fig. 3). In the male the first antenna1 segment reaches C D
Fig. 3. A. Antenna of Epicaztta virgulata (Lee.), male. B. Antenna of Epicauta hirsutipubescens Mayd., male. 0. Metatroehanter of Epi- cauta virgulata, male. D. Metatroehanter of Epicauta hirsutipubescens, male.
nearly to the hind margin of the head and is equal to the following four in length.
It is deeply excavated ex-
ternally near the apex. Second segment small, two- thirds as long as third, which is also broader. The sec- ond to sixth segments are dorso-ventrally flattened, the ventral surface of the second to fourth smooth and ap- parently forming a clasping organ, opposing the an- tennal excavation. Middle femora and trochanters de- nuded behind, flattened and slightly excavated, margined ventrally with a few long hairs and also dorsally on the trochanters.
Specimens from Lower California have the body col-



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110 Psyche [~ept.
or dark brown to black, the legs rufous. The Sinaloa
and Arizona specimens have the legs of the same color but the body color paler so that the contrast is not as great. I can find no other differences.
There is a slight
variation in the width of the antennal segments but it oc- curs in the Lower California and Arizona specimens alike. The pubescence is composed of hairs which are brown at the base and cinereous apically. The brown zone may be up to two-thirds of the length of the hair or reduced to less than one-third, thus affecting the gen- eral color of the insect considerably. Lower California specimens in general have more brown than Arizona specimens.
Localities: Lower California: Comondu; 5 mi. So. of San Miguel, San Domingo; San Quentin; Coyote Cove, Conception Bay; Venancio ; Triunfo; 10 mi. S. of Cata- vina ; La Paz ; Todos Santos ; all in the southern district. Sinaloa : Los Mochis. Arizona : Ehrenburg, Yuma Co. ; Cave Creek, Maricopa Co. ; Gillespie Dam, Maricopa Co. ; Florence, Pinal Co. I am very much indebted to the California Academy for permission to study the Lower California and Sinaloa specimens.
Epicauta hi~sutipub escens (Mayd.)
Macrobasis hirsutipubescens Maydell, 1934, Trans. Am. Ent. Soc. 60: 334.
Epicauta virgulata, Werner, 1945, Bull. M.C.Z. 45: 512 (in part).
This species can be distinguished from virgulata by the shape of the hind trochanters (Fig. 3) and by the shorter first antennal segment and lack of long hairs on the middle femora of male. In the male the first an- tennal segment reaches the hind margin of the eye and is equal to or slightly shorter than the following three, and is not as deeply excavated as in virgulata (Fig. 3). The second to fifth segments are not flattened and ex- panded. The posterior trochanters of the male have a tuft of hairs on the posterior border as in the figure. West Texas specimens are usually black, with grey pubescence (as in the type) or with tan pubescence, in



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19491 Werner-Epicauta Ill
which the individual hairs are unicolorous. The discal stripe on the elytra is not as prominent as in virgulata and southeastern Arizona specimens. Arizona spec- imens, from the southeastern part of the state, have the ground color brown and the pubescence brown at the base and white at the apex, and with the discal stripe very distinct. There seems to be no morphological dif- ference between the two groups and it must be presumed that the range is continuous in northern Chihuahua. Occasional specimens from Arizona have the pubescence very similar to western Texas specimens. The south- eastern Arizona specimens tend to be a little stouter and shorter than the Texas series or southwestern Arizona virgu1a.t a.
Localities : Texas : Lozier Canyon, Terrell Co. ; Tor- nilla Flat, Big Bend Nat. Pk.; Marathon; Culbertson Co. ; Ft. Stockton ; McNary, Hudspeth Co. New Mexico : Organ, Dona Ana Co.; Hope, Eddy Co.; Hot Springs, Sierra Co. Arizona: Benson; Huachuca Mts.; Sta. Rita Mts; Globe ; Badger; Tubac; San Carlos ; Tucson; Patagonia ; Nogales ; Calabasas Canyon, Tumacacori Mts; Arivaca, Pima Co.




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