Atrusca bella (Bassett, 1881)

Figs 47–74

Synonymy
Cynips bella Bassett, 1881: 93, female, gall.
Dryophanta bella: Mayr 1881: 36.
Andricus bella: Ashmead 1887: 127.
Holcaspis macullipennis Gillette, 1894: 236, female, gall. Synonym in Weld 1926: 18.
Disholcaspis bella (Bassett): Dalla Torre & Kieffer 1910: 356.
Disholcaspis macullipennis: Dalla Torre & Kieffer 1910: 375.
Cynips macullipennis: Felt 1918: 100.
Diplolepis bella: Weld 1926: 18.
Cynips (Atrusca) bella Bassett: Kinsey 1930: 285, female, gall.
Cynips bella variety bella Bassett: Kinsey 1930: 289.
Cynips bella variety vanescens Kinsey 1930: 292, female, gall, syn. nov.
Cynips (Atrusca) (bella) vanescens Kinsey 1936: 326.
Atrusca bella (Bassett): Weld 1951: 637.
Atrusca vanescens (Kinsey): Weld 1951: 638.

Types examined

The type of Cynips bella is deposited in the Entomology Type Collection at the Academy of Natural Sciences of Philadelphia: “Type number: 10442. Cynips bella Bassett, 1811, female, Arizona”. The type was not examined by the authors.

Material examined

17 females “USA, Arizona, Chiricahua Mnts. western side, ex Q. arizonica, AZ8, gall type 37, leg. J.A. Nicholls 2007.10.25”; 2 females “USA, Arizona, Molino Basin campground, Santa Catalina Mnts., ex Q. oblongifolia, AZ2, AZ3, gall type 37, leg. J.A. Nicholls 2007.10.28”; 3 females “USA, Arizona, Chiricahua Mnts. summit, ex Q. arizonica, AZ5, gall type 37, leg. J.A. Nicholls 2007.10.26”; 1 female “USA, Arizona, Sonoita, ex Q. arizonica, AZ7, gall type 37, leg. J.A. Nicholls 2007.10.26”; 11 females “USA, Arizona, 5 km N of Payson, ex Q. turbinella, AZ11, gall type 37, leg. J.A. Nicholls 2007.10.29”; 26 females “USA, Arizona, 25 miles S of Flagstaff on I17, ex Q. turbinella, AZ9, AZ10, gall type 37, leg. J.A. Nicholls 2007.10.31”; 2 females “USA, Arizona, Sedona, ex Q. turbinella, AZ1, gall type 37, leg. J.A. Nicholls 2007.10.29”. Two non-paratype females “Prescott, Ariz, female 11.27.35, gall 11.15.35”, “Q. gambelii E.R Leach coll.”, “Cynips vanescens Kinsey det. 35”.

Gall (Figs 60, 74)

Large spherical galls on the underside of leaves, with a suspended inner cell, to 3.0 cm in diameter, yellow with red speckles when young, uniformly red-brown when mature.

Biology

The asexual generation is only known. Leaf galls on Q. arizonica, Q. grisea, Q. oblongifolia, Q. rugosa (= Q. reticulata), Q. toumeyi, Q. turbinella. Galls mature in late autumn; adults emerge from January next year.

Distribution

USA: CO, AZ, NM

Atrusca bella (Bass.) 1881. Canad. Ent. 13:93. Gall on Q. arizonica, oblongifolia, toumeyi, subturbinella. Ariz, N. Mex.

Quercus arizonica, oblongifolia, toumeyi, reticulata [rugosa], subturbinella [turbinella]
Leaf galls
Detachable
Fig 87.

Diplolepis bella

Cynips bella
Holcaspis maculipennis

H. maculipennis was described from a single specimen from the west slope of the Organ Mountains in New Mexico. Without seeing this type Beutenmueller and Fullaway have erroneously determined a large oak apple on Quercus garryana from Oregon and northern California as this species. This has since been described as Cynips mirabilis Kinsey (see p. 64). The writer has compared the Gillette holotype of maculipennis with a Bassett type of bella in the National Museum and finds they are the same. Because of the percurrent parapsidal grooves and very oblique hind margin of the second tergite Mayr, in 1881, placed the species in Dryophanta — now known as Diplolepis.

This species, described from an unknown oak from Tucson, Ariz., has been reared by the writer from galls on Quercus arizonica, toumeyi, grisea, and undulata, and the galls found on oblongifolia and reticulata [rugosa]. Galls were seen in the Santa Catalina Mountains at Oracle and in Sabino basin, in the Santa Rita, Tumacacori, Patagonia, Huachiica, Mule, and Chiricahua Mountains, and at Nogales, Bisbee, Prescott, Hackberry, Ashfork, and Williams, Ariz. In New Mexico they were seen in the Burro Mountains, at Fierro, Kingston, Hillsboro, Nogal Canyon, Magdalena, Blue Canyon near Socorro, and in Sandia Mountains at Abo Pass and Tijeras. The galls were nearly full grown on arizonica in the Huachucas on July 9, and at Hackberry on undulata contained pupae on October 6. At Tijeras they were common on undulata, and on November 1 contained adults just beginning to emerge. A lot of flies cut out on that date lived in a pill-box without attention until December 30, and three were still living on January- 12. Few of the galls were parasitized here. In the Chiricahuas only six adults were secured by opening 65 galls, and in the Santa Ritas only one in fifty contained a producer.

Cynips bella, n. sp.

These belong to the class known as oak-apples. They are attached by a minute sessile point to the under side of the leaves of an oak found in Arizona--often near the margin of the leaf, but more commonly on or near the mid-vein. They are perfectly round, and those that have escaped the attack of parasites are quite uniform in size, measuring from 3/4 to 7/8 of an inch in diameter. Those stung by parasites are generally much smaller, and this species is so subject to their attacks that more than three fourths are thus affected. The galls (when dry) are of various shades of brown, mostly smooth but not polished; a few specimens have a decidedly russet color and a rough surface. The shell very thin and brittle. Each gall contains a single larval cell which is kept in a central position by fine, silky, radiating fibers, that reach from it to the outside covering. Besides these fibres, there are others that are attached to the inner surface of the shell, but which are not attached to the larval cell. They are much finer than the others and resemble coarse wool. Except that these galls are smaller, and the internal structure more delicate, and the surface less smooth and polished, they might easily be taken for those found on Quercus rubra--C inanis.

Cynips (bella) bella Bassett
agamic form

Cynips bella Bassett, 1881, Canad. Ent. 13:93.
Holcaspis maculipennis Gillette, 1894, Canad. Ent. 26:236. Beutenmüller, 1909, Journ. N.Y. Ent. Soc. 17:46.
Cynips bella bella Kinsey, 1930, Ind. Univ. Studies 84-86; figs. 45, 263, 272, 280. See the last reference for a more extended bibliography.
[NOT Holcaspis maculipennis err. det. Beutenmüller et al., in references to Pacific Coast material which is correctly Cynips mirabilis Kinsey.]

GALL.-Similar to all galls of the C. bella and C. dugèsi complexes, apparently indistinguishable from galls of C. (dugèsi) simulatrix, C. (dugèsi) subnigra, and C. (dugèsi) emergens which occur in various parts of the range of the present species. Mature galls rosy or brownish tan, uniformly colored or only obscurely mottled; often large; up to 27. mm., averaging nearer 20. mm. in diameter.

HOSTS.—Quercus grisea, Q. undulata, Q. chihuahuensis, Q. oblongifolia, Q. arizonica, Q. sacame [arizonica], Q. diversicolor [rugosa] (acc. Weld), Q. Gambelii, and Q. Toumeyi (acc. Weld). Apparently on all of the white oaks of the area.

RANGE.-Arizona: Safford. Oracle. Courtland. Fort Huachuca, Bis bee. Santa Catalina Mts. near Tucson (types of bella). Santa Rita Mts. Tumacacori Mts. Patagonia Mts. Chiricahua Mts. Mule Mts. Nogales. New Mexico: Tijeras. Blue Canyon near Socorro. Abo Pass. Nogal Canyon. Burro Mts. Fierro. Near Alamogordo at 7000'. Highrolls. Moun tain Park. Hillsboro. Kingston. Organ Mts. (types of maculipennis). Soledad Canyon in Organ Mts. (Above records in detail in Kinsey 1930: 290.) Embudo Canyon in Sandia Mts. (galls. E. B. Williamson in Kinsey coll.). San Marcial, 24 S (galls, Q. grisea, Holloway in Kinsey coll.). Mayhill (galls, Q. Gambelii, Holloway in Kinsey coll.). Magdalena (Q. undulata, Kinsey coll.). Las Cruces, 16 E (= Organ Mts.; Q. grisea, Kinsey coll.). Chihuahua: Pacheco, 20 E, 5400' (Q. saca me). Pacheco, 13 NE, 7400' (Q. sacame, galls on Q. Gambelii). San Buenaventura, 3 E, 5600' (Q. sa came, Q. chihuahuensis). Las Cruces, 15 N, 6500' (Q. chihuahuensis). Apparently one species throughout the southern halves of Arizona and New Mexico and the northern half of Chihuahua. Known from Oracle and Safford (possibly from Prescott), Arizona, and from the Sandia Mountains, New Mexico, southward to Las Cruces in Chihuahua. Figure 96.

LIFE HISTORY..—Galls: Nearly mature July 9; mature August 16, 22. Adults: October 25, 30. November 1. December 2, 10, 21, 26. Janu ary 1, 2, 10, 20, 25, 26, 29, 30. February 1, 5, 6, 10, 14, 15, 20, 28. Only stray adults before December. Most of the emergence in mid-December in Arizona and New Mexico, but in January in Chihuahua.

Throughout the whole of the southern half of Arizona and New Mexico and the northern half of Chihuahua, there seems to be but a single species of the bella complex, namely the typical species bella. We do not know of any other cynipid which ranges over as large a portion of our Southwest and Mexico. Within nearly the same area, there are three species of the dugèsi complex, producing galls which are apparently indistinguishable from the galls of bella; but repeated study of our more than 800 insects fails to show a basis for recognition of more than one species of bella in this area. Statistical studies might show differences in averages in the size of the areolet, and in the sizes of the spots in the radial and the cubital cells; but the limits of individual variation and the averages discernible on ready in spection do not show any differentiation into species. At one time it appeared to us that the insects from the Organ Mountains in New Mexico (= maculipennis Gillette) were, together with the Northern Chihuahua material, distinct from the rest of the Southwestern material in having larger areolets and more fused spots in the radial and cubital cells; but subsequent restudy of the material does not confirm that first impression. It is to be noted, however, that our Arizona series are not as large as those from Chihuahua, and additional material from Southern Arizona would provide a better basis for determining the limits of true bella.

A physiologic item is in part responsible for some doubt as to the identity of the Arizona and Chihuahua material. The Arizona insects emerge for the most part in mid-December; our Organ Mountain and Chihuahua material agreed in emerging, for the most part, in January and even early February. This may or may not be associated with specific distinctions.

C. (dugèsi) emergens, in Chihuahua, ranges as far south as Santa Ísabel. C. bella does not go as far south. It is C. (bella) pomifera, which is found in the Sierra from Namiquipa to Santa Ísabel, in Chihuahua.

From all other species of the complex, bella is distinguished by the more abundant and finer spots in the cubital cell, by the more massive, more complex spot in the radial cell, and by the larger areolet. While any one of these characters may fail to characterize individuals, the combination of characters clearly differentiates series of any size.

Cynips (bella) vanescens Kinsey
agamic form

Diplolepis bella err. det. Weld, 1930 (northern Arizona records only), Proc. U.S. Nat. Mus. 68 (10): 18.
Cynips bella bella err. det. Kinsey, 1930 (Prescott, Ariz. record only) Ind. Univ. Studies 84–86: 289.
Cynips bella vanescens Kinsey, 1930, Ind. Univ. Studies 84-86; 292, figs. 45, 282.
Diplolepis bella err. det. Weld, 1930, Proc. Ent. Soc. Wash. 32:29.

GALLS.—Very similar to all galls of the C. bella and C. dugèsi complexes. Mature galls rosy or brownish tan, not mottled, up to 28. mm., averaging near 20. mm. in diameter.

HOSTS.—Definitely on Quercus subturbinella. The record of Q. grisea for the types is less certain. No records available to show whether other white oaks in the area are also involved.

RANGE.-Arizona: Globe (types). Apache Trail at Fish Creek (galls only, Kinsey coll.). Cave Creek (Weld coll.). Prescott (Kinsey coll. and E. R. Leach, Jr., in Kinsey coll.). Hackberry, Ashfork, Williams (Weld coll.). Utah : Leeds, 4 W (Q. subturbinella). Pine Valley (Q. subturbinella). Zion Park (Q. subturbinella). Apparently ranging from Southwestern Utah (and Southern Nevada?) through the northern half of Arizona as far south as the Apache Trail and Globe. Figure 96

LIFE HISTORY.--Adults: November 20, 27. December 14. Mostly before January 20. Some after January 20

Originally described from a single insect from Globe in Central Arizona, this species is now recovered from several localities in Northern Arizona and in Southwestern Utah. While the new material makes modifications in our description of the species, the identity of the Utah and Arizona material seems certain, for some of the Utah specimens fully match the type in having the spots faint and reduced in all cells, including the cubital cell. The available locality records for this insect now mark the limits of the range of the host, Q. subturbinella (and its relatives?). This is an interesting scrub oak with Californian affinities. On the same oak, in the same area, Cynips (dugèsi) capronae produces a gall which is (ordinarily?) distinguishable by its heavy purple striping. In series the insect of vanescens is recognizable from other species in the bella complex by its combination of a smaller size, a very black body, and a small areolet.

Atrusca bella
Oak-apple-gall wasp
[Page 193]

Hosts: Quercus arizonica, oblongifolia, toumeyi, rugosa, turbinella

Galls can be beige, pink, or yellow-green in the shade, but always have a smooth skin with a dusty bloom across the otherwise glabrous surface.

Cynips bella variety bella
agamic form

Cynips bella
Dryophanta bella
Andricus bella
Holcaspis maculipennis
Diplolepis bella
Disholcaspis maculipennis
Cynips maculipennis
Dryophanta maculipennis

GALL. — As described for the species, apparently indistinguishable from the galls of other varieties of this species and of Cynips dugesi. On Quercus grisea, Q. undulata, Q. undulata var. pungens ( = Q. wrightii) , Q. Gambelii, Q. Toumeyi (acc. Weld), Q. oblongifolia, Q. arizonica, Q. diversicolor (acc. Weld; =Q. reticulata), and probably related oaks. Figure 263.

RANGE. — New Mexico: Magdalena ( Q . grisea, Weld inch Kinsey coll.). Blue Canyon near Socorro, Abo Pass (in Sandia Mts.?), Nogal Canyon, Burro Mountains, Fierro, and Tijeras (galls, acc. Weld 1926). Near Alamogordo at 7000 ft. ( Q . arizonica, also galls on Q. undulata, Kinsey coll.). Highrolls (galls, Q. undulata, Kinsey coll.). Mountain Park (galls, Q. undulata var., L. H. Bridewell in Kinsey coll.). Hills- boro ( Q . grisea, Kinsey coll.). Kingston (galls, Q. grisea and Q. Gam- belii, Kinsey coll.). Organ Mountains (R. R. Larkin, Q. Wrightii; maculipennis types). Soledad Canyon in Organ Mountains ( Q . arizonica, L. H. Bridewell in Kinsey coll.). Arizona: Prescott ( Q . grisea, Kinsey coll.). Safford, Oracle, Courtland, Fort Huachuca, and Bisbee (galls, Q. arizonica, Kinsey coll.). Tucson (= Santa Catalina Mountains? Cox coll., bella types). Sabino Trail in Santa Catalina Mountains and Santa Rita Mountains ( Q . ob- longifolia, Q. arizonica, Kinsey coll.). Tumacacori Mountains, Patagonia Mountains, Chiricahua Mountains, Mule Mountains, and Nogales (galls, acc. Weld 1926). Probably confined to the desert mountain ranges of more southern New Mexico and Arizona (and adjacent Mexico?). Figure 45.

This is the most widespread variety of the species. The oak-inhabited mountain ranges of this part of the Southwest are isolated by broad deserts, but the available insect material does not show variation enough (unless in the size of the areolet) to warrant a distinction of varieties in this whole area. Weld, however, records galls from Hackberry, Ashfork, and Williams in Arizona, and these more northern localities may represent some other, as yet undescribed variety if the distribution of this insect agrees with that of most of the other Cynipidae of Arizona. The material from the Apache Trail country of Arizona represents a distinct variety, vanescens.

It is surprising to find so many oaks serving as hosts of this one variety, but as far as I can determine they do not effect the isolation of distinct varieties. In this respect bella parallels Cynips dugesi simulatrix.

Weld found nearly full-grown galls in southern Arizona (Huachuca Mts.) as early as July 9, and I have fully grown galls dated August 16 and 22. Weld found pupae in galls at Hackberry (representing another variety?) on October 6. He found mature adults emerging from the galls as early as November 1 (1921), and sent me a wasp which was alive for almost three months (until nearly the end of January) after thus coming out of the gall. There were a few live adults left in the galls I collected in New Mexico at Alamogordo on December 21, and at Hillsboro on December 26 (1919), and in Arizona in the Santa Catalina Mts. on January 1 (1920); and these insects emerged soon after collecting. Last winter (1927-28 I had adults emerge from Organ Mountain material on January 2. Weld secured one lot of galls at Tijeras, New Mexico, which were only scantily parasitized, but records only 6 gall makers left in 65 galls collected in the Chiricahuas, and one in fifty in Santa Rita specimens. In my own experience I have never found very high parasitism in this species, tho it might well be expected locally.

I have examined the types of both bella and maculipennis, and checked them with series representing the wide range and hosts of the present insect. I had already concluded that the two names were synonyms when Weld published the same opinion. The types of bella and of maculipennis were collected at points 270 miles apart but well within the limits of the range of the present insect. The hosts of the types were not the same, but both are represented in our recent collections. As we now understand it, the only insect of the region with which bella can be confused is Cynips dugesi simulatrix, but altho the galls of these two are absolutely indistinguishable, the insects are abundantly distinct.

Cynips bella variety vanescens, new variety
agamic form

GALL. — As described for the species, apparently indistinguishable from the galls of the other varieties of bella and probably from an as yet undescribed variety of dugesi that may occur in the same region. On leaves of Quercus grisea.

RANGE. — Arizona: Globe (Kinsey coll.). Apache Trail at Fish Creek Probably restricted to a limited area that lies east of Phoenix in Arizona. Figure 45.

Most of the insects of this variety had emerged at Globe, Arizona, before January 20 (in 1920), but the type female emerged after that. It is never good practice to publish a new species on the basis of a lone specimen, but it is perhaps permissible when the new form is clearly differentiated from a group of related things whose variation, range, and host relations we already understand.