New Plant Galls. II—Description of Seven New Species of Gall-mites and the Galls which they Cause

By K. P. Lamb, Plant Diseases Division, Department of Scientific and Industrial Research, Auckland

Forelegs 26μ long; featherclaw 8μ long with 3 compound lateral rays and a simple bifid tip; claw bristle moderately curved, 8μ long; bluntly rounded; tarsus 5μ; tibia 4μ long with a dorsal seta. Hind-legs 23μ long; featherclaw and claw bristle as above; tarsus 6μ long; tibia 5μ long. Thoracic setae I, 4·5μ long, directed inwards. Thoracic setae II, 17μ long. Thoracic setae III, 26μ long, external to II and located on the middle of rear coxa.

Abdomen with 76–78 unifrom rings with oval, slightly pointed microtubercles located on their rear margins; 58 post genital rings. Lateral setae 28μ long on ring 12 or 13. Ventral setae I, 65μ long located on 14th postgenital ring. Ventral setae II, 18μ long, located on 28th postgenital ring. Ventral setae III, 24μ long located on 6th or 7th from rear. Caudal setae about 90μ long. Accessory caudal setae 8μ long, erect.

Epigynium, cup-shaped, 21μ wide, 14μ long, located a moderate distance from coxae. Coverflap with a single row of longitudinal striations, about 4 on each side. Genital setae 30μ long, directed caudad (Fig. 2).

Male: Not seen.

Type locality: Waitemata Harbour, Auckland, N.Z.

Collected by the writer, March 19, 1948.

Host: Salicorma australis Soland.

Relation to host: Causing and dwelling in galls on shoot.

Type material: Type slide so designated and with the above data. Located in the collection of the Plant Diseases Division, D.S.I.R., Auckland, N.Z.

Discussion: Only two gall-mites were recorded from Salicornia by Nalepa (1929); both from S. fruticosa L. They are.

The gall of E. salicorniae Nal., described by Houard (1922) and by Mimeur (1949), is of the witches' brooms type, and therefore is quite distinct from the local form.

In addition to the difference in gall structure, Accria rubifaciens sp. nov. may be separated from the above species by the following key:

Family Elaeocarpaceae Elaeocarpus dentatus Vahl.

21. Gall: Leaf erineum.

Description: Numerous white, more or less circular, elevated, discrete patches of erineum 2–3 mm. in diameter occur on the lower (abaxial) leaf surface. Older erineum is brown in colour (Fig 4)

Distribution: Collected on several occasions at Titirangi, Auckland.

relatively long claw-bristle of the second pair of legs and the delicate nature of the body setae. The mites of this group are:

The name E. dactylonyx typicus was applied to a more complete description of E. dactylonyx from further plant material from Bandoeng, Java. The validity of the subspecific name is therefore doubtful. In the generic classification of Keifer (1944) the above mites fall in the genus Aceria Keifer, 1944, so the following new combinations are recorded:

Aceria dactylonyx (Nalepa, 1914).

Aceria dactylonyx var. anonymus (Nalepa, 1921).

No reliable morphological distinction can be drawn between A. dactylonyx and A. dactylonyx var. anonymus from their descriptions. Possibly the variety was erected because of the plant host difference.

Though differing by the characters given below, the close affinity of the gallmite from Elaeocarpus dentatus with A. dactylonyx justifies its description as a new subspecies. A dactylonyx titirangiensis subsp nov. may be separated from A. dactylonyx (Nal.) by the second ventral setae, which are less than half the length of the first ventral setae and by the lateral setae, which are longer than the dorsal setae.

In A. dactylonyx (Nal.) the second ventral setae are at least two-thirds the length of the first ventral setae and the lateral setae are equal to or shorter than the dorsal setae.

Family Epacridaceae
Dracophyllum recurvum Hook.
Dracophyllum subulatum Hook

22. Gall: Terminal bud gall (Fig. 5).

Description: Terminal buds are uniformly swollen up to 8 mm. in diameter. In transverse section the gall is seen to be made up of closely packed leaves.

Distribution: Common in Tongariro National Park area.

Cause: The new species of Eriophyid mite described below has been found in abundance in young galls, but does not occur in older galls.

It is possible that the gall-mites migrate from galls when the buds cease active growth. Older galls often contain various insects and mites which are probably not concerned in gall formation. The Eriophyids are white in colour.

Eriophyes von Siebold

Von Siebold, C. Th., 1851, Jahresber. Schles Ges, 28, 89.

Nalepa, A., 1898, Das Tierreich, 4, 5.

Keifer, H. H., 1944. Bul Dept. Agric. Calif, 33 (1), 18–38.

Eriophyes dracophylli sp. nov.

Female: Length 200μ Body elongate, vermiform, 43μ thick, more or less cylindrical in cross-section. Rostrum 16μ long, directed antero-ventrally at an angle of 45 degrees. Thoracic shield subtriangular, 36μ wide and 30μ long, with

a characteristic pattern of dorsal striae (Fig. 7). Two dorsal detae 8μ long and 18μ apart, situted approximately one third of the distance from the base to the apex of the shield and directed anteriorly.

Forelegs 21μ long, tibia 4μ long, tarsus 2μ long, claw-bristle 6μ long without a knob, featherclaw 6μ long with a bifid tip, three major lateral rays then a short basal pair. Hindlegs 21μ long, tibia 3μ long, tarsus 2μ long, claw-bristle and featherclaw as above. Thoracic setae I, 3μ long; thoracic setae II, 10 long; thoracic setae III, 26μ long. Sternum bifurcate at level of thoracic setae II.

Abdomen with 58–60 uniform, microtuberculate rings. Lateral setae 22μ long, located on fourth abdominal ring. Ventral setae I, 43μ long, located on 14th postgenital ring. Ventral setae II, 5μ long, inconspicuous, located on 27th poatgenital ring. Ventral setae III, 16μ long, located on seventh ring from rear. Caudal setae 40μ long. Accessory caudal setae minute, located between and slightly posterior to caudal setae.

Epigynium bowl-shaped, 21μ long, located a moderate distance from the coxae. Genital coverflap with a single row of longitudinal striae. Genital setae 5μ long, directed posteriorly (see Fig. 7).

Male: 160μ long; 40μ wide.

Type locality: Tongariro National park, N.Z.

Collected by Miss E. Bray, July 2, 1950.

Host: Dracophyllum recurvum Hook. (? hybrid).

Relation to host: Dwelling in bud galls.

Type material: Type slide so designated and with the above data, located in the collection of the Plant Diseases Division, D.S.I.R., Auckland, New Zealand. A single paratype slide so designated, with the same data, is also in this collection.

No gall-mites have previously been recorded from this plant family which, according to Cheeseman (1925) is almost wholly confined to Australia and New Zealand. The short dorsal setae and characteristic shield pattern of E. dracophylli sp. nov. distinguish it at once from any known New Zealand species of Eriophyes.

Family Ericaceae
Gaultheria depressa Hook.

23. Gall: Witches' brooms (Fig. 6).

Description: Witches' brooms of short shoots bearing green to dark red aborted flower buds with thick fleshy calyces occur in masses up to 3 cm. across.

Distribution: Tongariro National Park Mt. Holdsworth, Tararua Rg.

Writing of Gaultheria antipoda, Cheeseman (1925) said: “A variable plant in most of its characters, particularly in the fruiting calyx, which may be greatly enlarged, highly coloured, and succulent, or may remain dry and unaltered. Both succulent and dry calyces may be found on the same branch.” This account suggests infestation by Eriophyid mites and that Cheeseman regarded it as a normal condition shows how widespread infestation must be.

Cause: The new species of Eriophyid mite described below.

Vasates Shimer

Shimer, 1869, Trans. Amer. Ent. Soc., 2, 319.

Keifer, H. H., 1944, Bul. Cal Dept. Agric., 33, 25,

Family Haloragidaceae
Haloragis depressa Walp.

24 Gall: Eriophyid leaf or bud gall (Fig. 10).

Description: The galls appear as red, sessile swellings, 3–5 mm in diameter, solitary or in groups upon the buds or stems. Early stages as seen on the edges of leaves take the form of small irregular proliferations of red-coloured tissue, wrinkled or folded in varying degrees.

Distribution: Brown's Bay, Auckland.

Cause: The new species of Eriophyid mite described below was found in small numbers in the galls. The mites were light brown in colour.

Thamnacus Keifer

Keifer, H. H, 1944, Bul Calif Dept Agric., 33 (1). 27.

Thamnacus haloragi sp. nov.

Female: Length 125–185μ Body more or less spindle-shaped, 60μ thick. Rostrum 22μ long, directed downwards. Thoracic shield sub-triangular, 38μ long and 42μ wide, produced in a broad, median, rectangular posterior lobe to behind the level of insertion of the dorsal setae. The shield indistinctly striated, but with strong granulation and sculpturing near the lateral margins Two dorsal shield setae 12μ long and 23μ apart, located on the posterior shield margin.

Forelegs 35μ long. Featherclaw 5μ long with three delicate lateral rays and a slender bifid tip. Claw-bristle 6μ long with a slight knob. Tarsus 6μ long. Tibia 6μ long Hindlegs 33μ long. Featherclaw 6μ long and as above. Clawbristle as above. Tarsus 5μ long Tibia 6μ long. Thoracic setae I, 5μ long. Thoracic setae II, 12μ long. Thoracic setae III, 25μ long Sternal ledge simple, extending to the level of the inner epimeral angle.

Abdomen with a broad dorsal arch flanked on either side by a shallow furrow extending to the cauda. With 41 broad, smooth tergites and 48 microtuberculate post-genital sternites. Lateral setae 16μ long, located on about the 9th abdominal ring. Ventral setae I, 42μ long, located on the 15th post-genital sternite. Ventral setae II, 10μ long, located on the 26th post-genital sternite. Ventral setae III,

20μ long, located on the 5th ring from the rear. Caudal setae about 30μ long. Accessory caudal setae lacking.

Epigynium bowl-shaped, 22μ wide, 13μ long, located a moderate distance from the coxae. Genital coverflap with a single row of longitudinal striations. Genital setae 10μ long, located on the lateral margins of epigynium and directed posteriorly (Fig. 9).

Male: Not studied.

Type locality: Auckland, N.Z.

Collected: Miss J. Dingley, Brown's Bay, Auckland, on October 2, 1950.

Host: Haloragis depressa Walp.

Relation to host: Causing and dwelling in bud and leaf galls.

Type material: Type slide so designated, with the above data.

One paratype slide from the same material and one paratype slide from leaf galls on H. depressa collected in the Waitakere Ranges, Auckland, on October 8, 1950, by Miss J. Dingley. All the type material is located in the collection of the Plant Diseases Division, D.S.I.R., Auckland, N.Z.

Discussion: Nalepa (1920) recorded no Eriophyids from the Haloragidaceae; the only other known member of the genus, T. rhamnicola (Keif.) from California, differs from this species as follows.

Family MORACEAE Paratrophis microphylla Cockayne

25. Gall: Witches' brooms (Fig. 11).

Description: The witches' brooms are composed of loose masses of dark brown, erinose shoots, each shoot about 1 mm. in diameter, the whole mass being up to 10 cm. long and 4 cm. wide.

Distribution: Concerning this plant, Cheeseman (1925) wrote: “The spikes are often diseased and converted into large, much-branched panicles densely clothed with small imbricating bracts, the flowers being altogether aborted.” This probably refers to a form of the above witches' brooms.

Cause: The new species of Eriophyid mite described below.

Eriophyes paratrophi sp. nov.

Female: Length 135μ. Body more or less cylindrical, 37μ thick. Rostrum 17μ long, directed downwards at an angle of 45 degrees. Thoracic shield subtriangular, 30μ long and 32μ wide, with three major longitudinal striae. Two dorsal shield setae 25μ long and 12μ apart located slightly ahead of the rear shield margin and directed anteriorly.

Forelegs 27μ long, tibia 3μ long, tarsus 5μ long, featherclaw 5μ long with four lateral rays and a bifid tip, claw bristle 7μ long, with a small terminal knob. Hindlegs 25μ long, tarsus 5μ long, tibia 5μ long, featherclaw and claw-bristle as above. Thoracic setae I, 3μ long; thoracic setae II, 12μ long; thoracic setae III, 30μ long. Sternum simple, extending to the level of the inner epimeral angle.

The name Eriophyes fici has been variously attributed to Ewing or Essig. Baker (1939) reduced it to synonymy with Eriophyes ficus Cotte. The species in the above list together with E. paratrophi sp. n. may be separated by the following key:

Family Violaceae Melicytus ramiflorus Forst.

Acknowledgments

I wish to thank those persons who have kindly submitted plant material for study and also the Director, Commonwealth Institute of Entomology, for a copy of the original description of Eriophyes salicorniae Nal.