Daktulosphaira vitifoliae (Fitch)

An investigation was undertaken to determine the correct name of the grape phylloxeran. This action was desirable because more than one spelling of the specific name and more than one name combination are in current use for the species. The inquiry revealed that Daktulosphaira vitifoliae (Fitch) is the oldest available name for the species.

The grape phylloxeran, a native of North America, has been of economic importance since its accidental introduction into Europe and other viticultural centers of the world in the last century. At that time it virtually destroyed the grape industry in severely infested areas. Although the insect is no longer seriously destructive in some areas, it is injurious in others, and its symbionts, its biology, and its control are being studied. Federov (1959) discussed the injuriousness of the phylloxeran and stressed the need for its adequate control. Shaposhnikov (1967) stated, "This is the most serious pest of grapevine." Maillet (1957) gave an ex- tensive discussion, review, and bibliography of the species. Literature on the biology, morphology, ravages, and con- trol of vitifoliae is voluminous.

The names, spellings, accreditation of author names and the earliest noted publication of names of the grape phylloxeran are as follows:
[many synonyms are listed; see link or list above]

Although vastatrix was used extensively for several years after publication, it as well as the other specific names listed above have long been recognized as synonyms of vitifoliae .

Fitch (1855: 862, 1855: 158, 1857: 397) invariably called the insect whose galls he observed on grape leaves in New York State "the grape leaf louse (Pemphigus Vitifoliae)." Signoret (1869: 556, 565) spelled the name vitifolii. Planchon and Lichtenstein (1871: 5) stated that vitifoliae was incorrect and should be rectified to vitis folii. Riley (1871: 95) rejected their opinion, stating "... though "folii" would of course be more grammatically correct, one would suppose the Doctor [Fitch] had some reason for his conduct." Thomas (1879: 158) also indicated that the spelling should be vitis-folii or vitifolii, but he approved vitifoliae, and wrote "... names with the termination have been too long received for this to be a valid objection in this case." Grassi (1912: 10) suggested vitisfoliae as well as vitisfolii and vitifolii. All spellings except vitisfoliae have been used, with Europeans tending to use vitifolii and Americans usually using vitifoliae.

Article 32(a)(ii) of the International Code of Zoological Nomenclature states "... incorrect transliteration, improper latinization, and use of an inappropriate connecting vowel are not to be considered inadvertent errors. . ." Thus according to the Code, vitifoliae is the legal spelling of the name.

The generic name with which vitifoliae has been combined has varied. Fitch (1855, 1857) always, and Walsh (1863) originally, placed vitifoliae in aphid genera. Later Walsh (1866: 111, 1867: 284) indicated that Fitch erred in considering the insect an aphid, did not mention his own 1863 assignment, and stated (1867: 284) that the insect was "... a true bark-louse belonging to the Coccus family" and that it ". . . must become the type of a new and very aberrant genus."

Shimer (1866: 290) studied "Pemphigus vitifolia" stating, "The result of these investigations developes a new genus, of a new family, in the third division Monomera of the Homoptera, for this and another insect (also one of Mr. Walsh's coccus) found in a small subglobular gall on the leaf of the Pignut Hickory; and probably, some two or three other insects that I have seen. These may possibly comprehend more than one genus when more thoroughly studied."

Shimer (1866: 290) then described but did not name the genus, indicated that vitifoliae and possibly another species belonged in it, and stated, "The insect inhabiting the small gall on the Pignut Hickory (Caoja[!] glabra) and which doubtless is identical with that referred to by Mr. Walsh, P.E., 111, although the galls are mostly all larger than a "cabbage seed," I believed after careful examination of the female and larva to belong to the same genus as the "grape leaf louse," and suggested for it the species name of globosum."

The reference to Walsh and the size of the gall were the only statements that could be construed as a description of globosum. Walsh (1866: 111-112) de- scribed the gall referred to by Shimer as ". . . an undescribed gall the size of a cabbage-seed on the leaves of the Pignut Hickory (Carya glabra)." This presumably meets the requirements of Article 16(a) (viii) of the Code as an indication of a specific name, but it does not meet the requirements of Article 1 1(g) (ii) because globosum was not combined with a generic name.

Shimer (1866: 365) referred to his earlier (1866: 290) article, named and briefly described the new genus Dak- tulosphaira and placed a single species, Pemphigus vitifoliae Fitch, in it but (p. 365) did not mention globosum. And he did not give the derivation of his new generic name which is, according to Steyskal (1974), a literal translation of the Greek.

The following year Shimer (1867: 2) described "Dactylosphaera. New genus" and gave the Greek from which the name was derived. This spelling, also according to Steyskal (1974), is a classical Latin transcription of the name. Shimer (1867: 2-11) also described "Dactylosphaera globosum, n. sp." placing that species before vitifoliae which he assigned to Dactylosphaera with a question. His only mention of his former articles was to state that in 1866 he had called vitifoliae the "Grape leaf louse." He (1867: 5-8) redescribed vitifoliae and stated "In case, however, the characters given above should be sufficient to separate, generically, vitifoliae from D. globosum, I would propose the generic name of Viteus for the former."

Walsh (1867: 24-28) immediately ac- cepted Dactylosphaera vitifoliae as the correct name for the grape leaf louse, while Riley (1871: 84) used Phylloxera vitifoliae, the name that was used much more frequently than Daktulosphaira vitifoliae or Dactylosphaera vitifoliae for many years.

Because Shimer' s original descriptions of globosum and Daktulosphaira were published in a farm journal of uncertain distribution, and because the articles were not cited in his 1867 publication where he described globosum and Dactylosphaera as new, the 1866 articles presumably were overlooked or ignored by some workers while others apparently assumed that Dactylosphaera was a correction of Daktulosphaira and that the name should date from 1867. Later Shimer (1869: 386-398) described or redescribed several phylloxeran species that lived in galls on hickories, placing them in Dactylosphaera. He (p. 392- 393) again mentioned D. globosum as a species living on hickories but did not use the name vitifoliae.

Pergande (1904: 236b-238) treated globosum as Phylloxera globosum , citing Shimer' s 1867 publication. Although Pergande did not discuss the status of Dactylosphaera, he presumably con- sidered the name a synonym of Phyl- loxera, because he placed in the latter genus the various species included in Dactylosphaera by Shimer in 1869. Pergande (p. 213) mentioned vitifoliae only in a quotation from Shimer 1867 and did not refer to Shimer' s 1866 articles.

Wilson (1910: 150, 155) listed Dactylosphaera Shimer 1867 with globosum the type, Daktulosphaira Shimer 1866 with vitifoliae the type, and Viteus Shimer 1867 also with vitifoliae the type. Borner (1930: 159, 162, 193) synonymized Viteus with Daktulosphaira, but later (1952: 212, 227) recognized as valid genera, Dactylosphaera with globosum as its type-species and Viteus with vitifoliae as its type-species, stating that Daktulosphaira (1866) with vitifoliae as its type was an error for Dactylosphaera (1867).

Prior to 1952, both while and after synonymous names were in use, Phylloxera vitifoliae was the most commonly used name for the species. Dactylosphaera vitifoliae appeared occasionally, and Daktulosphaira vitifoliae and Viteus vitifoliae were rarely cited. Since 1952 non- Americans have tended to use Dactylosphaera vitifoliae (or vitifolii) or Viteus vitifoliae (or vitifolii) while Americans, without critical consideration of the insect's name or relationships, have continued the use of Phylloxera vitifoliae.

Daktulosphaira falls under Article 32(a)(ii) of the Code because, in the original publication, there is no "clear evidence of an inadvertent error, such as a lapsus calami, or a copyist's or printer's error" and "(incorrect trans- literation, improper latinization. . . . are not to be considered inadvertent errors)." Since vitifoliae was the only species included in the genus, Daktulosphaira vitifoliae (Fitch) is the correct name for the grape phylloxeran, and Viteus is a synonym of the older generic name. Because there has not been unanimous use of one name in recent years, common usage would not be seri- ously disrupted by using Daktulosphaira vitifoliae, the name that merits general acceptance.

The identity of globosa is uncertain. Types of the species are not known to exist, and morphological characteristics of the insects have not been adequately diagnosed. Recognition of the species has depended primarily on the appearance of its galls which Shimer (1869: 392-393) indicated he believed he had confused with galls of Dactylosphaera caryae semen Walsh in his 1867 description of globosum. Pergande (1904: 213, 237) affirmed this opinion and redescribed and illustrated the galls of the two species. Shimer (1869: 393) also indicated that the trees on which he observed globosum and caryaesemen in 1867 were Carya amara instead of Carya glabra as he had previously reported. Pergande (1904: 213) noted galls of caryaesemen on Carya glabra in the Mississippi River Valley but did not state whether galls of glob- osum were present. I believe there may be some uncertainty concerning the true host(s) of globosa.

Perhaps it would be possible to collect galls and specimens of globosa and, after critical field and laboratory studies, determine the identity of the species. But until such studies are made, the status of globosa and Dactylosphaera will remain unclear.

Daktulosphaira vitifoliae differs morphologically and biologically from Phylloxera quercus Boyer de Fonscolombe (1834: 223-224), the type-species of Phylloxera Boyer de Fonscolombe (1834: 222), and the two are not con- generic. D. vitifoliae lacks prominent, tuberculate dorsal and marginal processes and lives in galls on the leaves and in cavities of swellings on the roots of Vitis. P. quercus has strongly developed, elongate processes on the dorsum and margin of the body in apterae and on the head and thorax in alatae. This species lives on the lower surface of the leaves of oak and does not cause galls.

Phylloxera vitifoliae Fitch

The life history of the phylloxera is quite complicated and. varies considerably, according to type of grape infested and the climate of the country inhabited by it. The phylloxera may be disseminated from nurseries on vines, or on vines from infested vineyards, and new centers of infestation come about principally in this way. In California spread from these centers is due to migration from infested vines over the soil, or through cracks in the soil of the small root-inhabiting nymphs or larvae (fig. 53). These small larvae may also be born6 by wind and by picking boxes, and in hilly or irrigated vineyards perhaps some are carried by water. The winged form in that State appears not to be a factor of importance in the dissemination of the species.

Phylloxera vitifoliae Fitch

Pemphigus vitifoliae
Byrsocrypta vitifoliae
Phylloxera vastatrix
Phylloxera vitifoliae

A small rough gall on either side of the leaf, usually, when present, in vast numbers. Another generation forms galls on the roots, causing considerable damage, especially in Europe. Common on wild and some cultivated grapes.

Phylloxera vastatrix

This insect is native east of the Rocky Mountains, where it has always lived upon wild vines and did not attract attention until it was imported into France about 1859, as it does practically no damage to the native American grapes. [ . . . ]

This aphid exists in several forms, which injure both foliage and roots. On the leaves irregular spherical galls are produced, and the root-inhabiting form produces galls on the roots. The leaf-galls are very common on American grapes, but are no indication of the presence of the root form, as the roots are rarely injured where the foliage is covered with leaf -galls. On the other hand the European varieties rarely exhibit any leaf-galls, but are very susceptible to the root phylloxera, which multiplies without any external indication of its presence until the vine is seriously injured. The injury to the vine is not due so much to the sap taken from the vine by the myriads of aphids which may inhabit the roots, as to their poisonous effect on the root tissue and its subsequent decay. Wherever the phylloxera attack the roots, small swellings are produced, composed of soft tissue which soon decays. When such a gall is formed at the end of a young root, its growth is stopped, and on larger roots a decay sets in which finally girdles the root and all below the injured point dies. As all the roots become affected the vine stops growing, the leaves be- come sickly and yellowish, and the vine dies, and the phylloxera disappears from the rotting roots, so that the cause of the injury would be obscure were the nature of the injury not known.

Life History. The life history of the phylloxera is a complicated one, involving four different forms of aphids; the leaf- gall form, the root or destructive form, the winged or colonizing form, and the sexual form. The winter eggs are deposited on the rough bark of the old wood in the fall and hatch the following spring. The young aphids settle on the leaves, where the irritation caused by their mouth-parts soon causes a depression around each which forms a gall projecting on the lower side of the leaf. "In about fifteen days the louse becomes a plump orange-yellow, full-grown, wingless female, and fills its gall with small yellow eggs, dying soon after. The eggs hatch in about eight days into young females again, like the parent, and migrate to all parts of the vine to form new galls. Six or seven generations of these wingless females follow one another throughout the summer, frequently completely studding the leaves with galls." In California the young hatching from the winter eggs go directly to the roots where they give rise to new colonies, there being no gall forms, according to Quayle. Where the leaf-gall females occur many of them probably migrate to the roots during the summer, and all do so with the approach of cold weather. In the spring the roots are attacked and a series of generations of wingless females multiply on them. As there are five to seven generations in a season and each female lays from 30 (Quayle) to 100 (Marlatt) eggs, it is evident that they will soon be numerous enough to destroy the vine. The root-inhabiting females are very similar to those in the leaf-galls, and are about one-twenty-fifth inch long when mature and half as long when young and active. They are light greenish-yellow in summer and darker in winter, and when numerous the infested roots look as if dusted in spots with powdered mustard, according to Quayle. He states that "the newly hatched insect is fairly active, and at first moves from place to place on the roots, but finally, when it reaches the egg-laying stage, inserts its sucking-tube into the root and remains fixed." During the late summer and early fall some of the root-lice develop into winged females which escape through cracks in the soil and fly to neighboring vines. They lay from two to four eggs beneath the loose bark on the old wood and soon die.

Phylloxera vitifoliae

Vitis
Leaf or tendril galls
Small, wartlike leaf galls on either the upper or the lower surface, diameter 2 to 3 mm

Phylloxera vastatrix Planchon

This destructive plant-louse is a native of the eastern United States, where it originally infested the leaves and roots of the various species of wild grapes. Sometime before 1863 it was introduced into the great wine-producing regions of France, and there proved a deadly enemy of the European grape (Vitis vinifera). By 1884 a third of the vineyards of France had been destroyed, and a much larger area had been seriously affected. It was introduced into California some time before 1874 and is now present in most of the grape-producing regions of the state except in the southern part. As most of the grapes grown commercially in California are of the vinifera or European type, the phylloxera has there been one of the most important insect pests with which the vineyardists of the Pacific slope have had to contend. The phylloxera has also been introduced into New Zealand and South Africa, and also occurs in southern Russia and in Algeria.

The life history of the grape phylloxera is a complicated one. In its destructive form it is a small, yellowish, wingless root- louse about ^ of an inch in length found clustering on the roots of the vine. In feeding, the louse inserts the sharp and slender stylets of the beak and sucks out the sap, thus causing an irritation which produces an abnormal enlargement of the roots known as nodules. These sweUings are yellow in color, soft and watery, and after a time break down and decay, causing the death of the root. The underground forms molt three times before becoming mature ; they are all females and re- produce without being fertilized. The number of eggs laid by a single individual varies considerably with the climate and the season, but rarely exceeds a hundred. The eggs are oval in form, yellow in color and about ^ of an inch in length ; they are laid singly or in clusters on the roots of the vine.

There may be six generations of the root-inhabiting form annually, and experimental rearing has shown that reproduction may continue in this way for several years without appreciable loss of vigor or of prolificness. Normally, however, during the latter half of the season some of the Uce infesting the roots become more elongate than the others and have longer legs and antennae. These forms do not become mature at the third molt and begin to lay eggs, but continue their development; at the fourth molt, wdng pads become visible on the thorax ; and at the fifth and last molt, which takes place after the nymph has crawled to the surface, functional wings are acquired. After waiting a few hours for the wings to dry and the body to harden, they take flight and, if a wdnd is blowing, may be trans- ported a considerable distance. After feeding about a day on the under side of one of the tender leaves at the end of the shoots they are ready to deposit their yellowish-white eggs of two distinct sizes ; from the larger eggs are developed the true females and from the smaller ones the true males. Both sexes are wingless, and the female after fertilization deposits a single so-called winter egg on the bark of the older canes. These sexual forms are much smaller than the others, and functional mouth parts are lacking. The insect does not pass the A\anter exclusively in the egg state, but many of the younger indi\aduals of the root-inhabiting form, as well as many of the later migrants from the leaves, hibernate in small groups on the larger roots.

The winter eggs hatch in the spring soon after the first grape leaves have become well expanded, and the young Uce normally crawl up the canes to the leaves, where they settle on the upper surface and begin sucking out the juices of the leaf. The puncture made in feecUng stimulates the growth of the leaf cells so that a hollow gall is formed, projecting from the mider side of the leaf and opening by a narrow slit on the upper surface (Fig. 390). The opening is guarded by a dense growth of do^\^l. Within this cavity the insect continues its develop-ment and becomes mature after the third molt, which occurs in about fifteen days. The forms producing the galls are all wingless females, and each individual of the earUer generation may lay from 500 to 600 eggs during the three weeks of her life as an adult. Towards the end of the season the later broods are not so prolific, 100-200 eggs being the maximum. The eggs hatch in about eight days, and the young escape from the gall by the opening on the upper surface of the leaf and migrate to the tender leaves at the end of the branches, where new galls are formed. From five to seven generations of the gall- inhabiting form occurs annually. Nearly all the young of the earlier generations migrate to the leaves, but after the third generation an increasing number migrate to the roots, where they join their underground sisters in their insidious attack on the vine.

The complete life history, as outlined above, occurs only when the phylloxera is living on the species of grapes more closely related to its native food-plant. In Europe and in California the leaf galls are rarely seen. Under these circumstances it is supposed that the lice hatching from the so-called winter eggs may migrate at once to the roots. That such is the case, however, does not seem to have been proved by direct observation.

Phylloxera vitifoliae Fitch
[Lasiopteryx arizonensis Felt is listed as emerging from this gall as well; it is presumably an inquiline]

Vitis
Leaf or Tendril Galls
Wart-like leaf galls, diameter 1/8 inch, aphid, summer