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Volume 79, 1951
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New Plant Galls: 1—Mite and Insect Galls

[Read before the Auckland Institute, September 20, 1950; received by the Editor, September 28, 1950]

Introduction

During a study of the plant galls of New Zealand a number of new ones were discovered. Those caused by mites and insects are described in this paper. It is proposed to publish a full list of the plant galls of New Zealand subsequently.

Materials and Methods

Material containing gall-midge larvae was confined over sterilized soil or peat as recommended by Barnes (1946). Galls containing other insect larvae or pupae were put in jars covered with gauze and left for the imagines to emerge. Often difficulty was encountered in rearing adult insects (especially Cecidomyidae) unless the larvae or pupae were nearly mature, because desiccation of the surrounding plant tissues frequently resulted in death of the insect. Thus galls were collected at different times of the year with the hope of securing insects at the right stage of development.

Eriophyid mites were mounted in modified Berlese fluid of the formula of Stewart and Freeborn (1937) with approximately 1 per cent. hydrochloric acid added. Unfortunately, Berlese fluid mounts are only semi-permanent, no method of permanent mounting having yet been devised. Polyvinyl alcohol, though recommended for mounting Acarina by various workers, was found unsatisfactory. Following the practice of Keifer (1939, 1944), type material has been described from Berlese fluid mounts, but where possible material from the same collection has been preserved in vials of picro-hydrochloric acid mixture according to the method of Nalepa (1906). The generic classification of the Eriophyidae tentatively adopted here is that of Keifer (1944).

A. Galls Caused by Acarina (Arachnida)
Family Verbenaceae

Avicennia officinalis L.

1. Gall: Leaf erineum* (Fig. 1).

Morphology: Few to many discrete, hemispherical swellings, 2–4 mm. in diameter, are located on the lower surface of the leaf. They are greyish green in colour (similar to the tomentum of the under surface) and frequently umbilicate. Often a small chlorotic patch is apparent on the upper surface of the leaf over a large gall. In heavy infestations of young shoots, the galls often fuse together, resulting in leaf distortion. Close examination shows the surface of

[Footnote] * An erineum (adj. erinose) is an abnormal proliferation of plant hairs.

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the gall to be composed of a compact mass of the terminal cells of epidermal hairs.

Cause: The gall is caused by a new species of eriophyid mite which is described below. The mites are found within galls at all seasons except winter, when only occasional eggs are found. In autumn mites have been observed migrating to terminal buds and laying their eggs on the abaxial surfaces of newly formed leaves.

Aceria avicenniae sp.n.

Female: Length 85–95μ. Body vermiform, 20μ thick. Rostrum 10μ long, directed anteroventrally. Thoracic shield 14μ long, triangular, not covering rostrum; longitudinally striated with six major furrows then one on either side extending halfway to base of shield. Shield setae 9μ long on rear margin and directed caudad.

Forelegs 15μ long, tibia 3μ long, lacking lateral spur, tarsus 3μ long, claw bristles 8μ long, slight knob, feather-claw 4μ long with 4 lateral rays and bifid tip. Hindlegs 14μ long, tibia 1·5μ long, tarsus 2μ long, claw bristle 7μ long, feather-claw 4μ long and as above. Thoracic setae I, 2μ long; thoracic setae II, 8μ long; thoracic setae III, 16μ long.

Abdomen with punctated tergites 63–70 in number. Sternites similar to tergites. Lateral setae inconspicuous, 4·5μ long; first ventral setae conspicuous, 17μ long; second ventral setae 6μ long; third ventral setae 8μ long; caudal setae about 45μ long.

Genital coverflap smooth, 12μ wide, located a moderate distance from coxae. Genital setae inconspicuous, 3μ long, directed backwards. (See Fig. 2.)

Male: Not studied.

Type Locality: Auckland, New Zealand.

Collected: January 19, 1950, by the author. Common in the Auckland Province wherever the host Avicennia officinalis is found.

Relation to Host: Causing and living in leaf erineum.

Type Slide: So designated, with the above data. Located in the collection of the Plant Diseases Division, Department of Scientific and Industrial Research, Auckland.

Inquiline: A Tarsonemid mite has been found on galls taken in Auckland.

This gall was recorded by Houard (1923,) No. 2785; and also by Docters van Leeuwen (1926), No. 20077 from Java and Sumatra, though the mite was not described. Baylis (1940) recorded the occurrence of these galls in New Zealand.

Family Convolvulaceae

Calystegia sepium (L.) R. Br.

2. Gall: Leaf pouch gall (Fig. 4).

Morphology: One to several pouch galls on the laminae of leaves. The galls are either solitary and globose or several and coalescing into an irregular swollen mass. The form of the gall depends upon the age of the leaf when initially attacked. Mature solitary galls are usually 2–4 mm. wide and about 3 mm. thick. They open to the

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adaxial leaf surface through a protruding, slightly curved beak. The dorsal surface of the gall is reddish brown in colour, while the ventral surface varies from light green to reddish brown.

Cause: Eriophyid mites of a new species described below are found inside the galls and are responsible for gall formation. The gall differs from that recorded by Swanton (1912) on Convolvulus arvensis L. (catalogue No. 688) caused by Eriophes convolvuli Nal. Bagnall and Harrison (1928) referred to a similar deformation, discoloured but without abnormal pilosity caused by Phyllocoptes convolvuli Nal. The local gall mites belong to the genus Vasates and the galls are quite distinct from the European galls caused by P. convolvuli as described by Rübsaamen (1911). The Calystegia gall mite must therefore be regarded as a new species.

Occurrence: Common on Calystegia sepium and Calystegia sp. (probably turguriorum) in the Auckland Province. Collected by the writer on several occasions.

Vasates calystegiae sp.n.

Female: Length 240μ, body more or less cylindrical, 75μ wide, 68μ thick, tapering posteriorly. Rostrum 23μ long, curving down at same angle as dorsal shield. Thoracic shield subtriangular, 42μ long, 62μ wide, apparently smooth. One pair of dorsal shield setae, 35μ long and 30μ apart, arising from prominent tubercles located at the rear margin of the shield and directed posteriorly.

Forelegs 38μ long: feather-claw 8μ long with 5 lateral compound rays and bifid tip; claw bristle 8μ long with a terminal knob; tarsus 8μ long; tibia 9μ long. Hindlegs 36μ long; feather-claw and claw bristles as above; tarsus 8μ long; tibia 9μ long.

First thoracic setae 8μ long, directed inwards. Second thoracic setae 15μ long, arising level with posterior edge of sternum. Third thoracic setae 29μ long, directed anterolaterally.

Abdomen with 50–55 tergites and about 50 postgenital sternites. The tergites smooth and dorsally broader than the microtuberculate sternites, but continuous with them. Lateral setae 25μ long on ring 8. First ventral setae 31μ long on ring 21. Second ventral setae 21μ long on ring 36. Third ventral setae 27μ long, located on fourth ring from rear. Caudal setae about 65μ long. One pair of accessory caudal setae 4·5μ long, located between and slightly posterior to caudal setae.

Epigynium 24μ wide, 18μ long, cup-shaped, located a moderate distance from the coxae. Coverflap apparently smooth. Three rows of micro-tubercles anterior to epigynium. Genital setae 18μ long, directed posteriorly. (Fig. 3.)

Male: Not studied.

Type Locality: Auckland, New Zealand.

Collected: By the author, February 2, 1950.

Host: Calystegia sepium (L.) R. Br.

Relation to Host: Causing pouch galls on leaf.

Type Slide: So designated, with the above data. Located in the collection of the Plant Diseases Division, Department of Scientific and Industrial Research, Auckland. New Zealand.

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Family Apocyanaceae

Parsonsia heterophylla A. Cunn.

3. Gall: Leaf erineum.

Description: A simple erineum occurs in irregular white patches on the abaxial leaf surface. The hairs are sparse and no other deformation is visible. An eriophyid mite of the tribe Phyllocoptinae is responsible for gall formation.

The above description is based on specimens collected from Smith's Bush, Takapuna, Auckland, on October 16, 1948, by Miss J. M. Dingley.

Family Fagaceae

Nothofagus cliffortioides Oerst.

4. Gall: Leaf pouch gall.

Description: One to many monothalamous pouch galls 0·5–1·5 mm. in diameter occur on the leaves (Fig. 6). The greater part of the gall appears as a globose, light green, swelling on the abaxial surface. About the circular opening of the gall on the adaxial surface there is a slightly raised rim.

Cause: Eriophyid mites of the genus Aceria occur within the galls in large numbers. Further work is required to determine the relationships between the mites infesting different species of beech and various organs of the trees.

Note: This gall has been collected from Cass, Canterbury, by Mr. J. A. Neal, 1948, and also from Tongariro National Park by the author in April, 1949. In both cases bud galls were found on trees with leaf galls. The bud galls are described in the following section. Morrison (1933) recorded the occurrence of leaf galls on this tree, but did not identify the mite causing them.

Family Fagaceae

Nothofagus cliffortioides Oerst.

5. Gall: Eriophyid bud gall (Fig. 6).

Description: The buds are enlarged to about six times their normal size. A typical gall was 6 mm. wide and 8 mm. long. The bud scales are considerably thickened and enlarged and there is a profuse production of hairs. Eriophyid mites (Aceria sp.) were taken from galled buds at National Park.

A species of mite (Eriophyes waltheri K.) has been described from witches’ brooms on Nothofagus menziesii in the United States (Keifer, 1939). The infested plants had been imported from New Zealand, and it was suggested that the mites had also originated from this country. While the bud gall mite somewhat resembles E. waltheri, it differs from it as follows:

(1)

Ventral thoracic pattern—absent in bud mite.

(2)

The second ventral setae of the local mite is relatively much shorter than in E. waltheri.

(3)

Accessory caudal setae appear to be absent.

(4)

The lateral shield pattern differs.

For the present, therefore, it would seem desirable to regard the bud gall mite as a different species.

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Family Leguminosae
Carmichaelia australis R. Br.
Carmichaelia subulata T. Kirk

6. Gall: Eriophyid cladode gall (Fig. 9).

Description: The cladodes bear rough, dissected, sessile swellings up to 2·5 cm. in diameter. They are grey in colour and pilose. This gall was described from fresh material of C. australis collected at White's Beach, Auckland, by Miss R. F. DeBerg on October 23, 1948. Similar material in the Plant Diseases Division herbarium was collected at Laingholm, Auckland, by E. D. Hatch, on February 13, 1945. Further material in the Plant Diseases Division herbarium was collected at Waipara by A. J. Healy in May, 1943. Fresh galled material of C. subulata was collected near Waipara in June, 1949, by Miss A. Lush. Tarsonemid mites (Tarsonemus sp.) accompanied the eriophyid mites in the fresh Waipara material. The causal Eriophyid is described below as a new species.

Aceria carmichaeliae sp.n.

Female: Length 103μ, vermiform, 38μ wide, 34μ thick, tapering posteriorly. Rostrum 18μ long, curving downwards. Thoracic shield subtriangular, 30μ wide, 23μ long, more or less smooth. Two dorsal shield setae, 18μ long and 18μ apart, located at the rear edge of the shield and directed posteriorly.

Forelegs 21μ long; feather-claw 5μ long, slender, 4-rayed; claw bristle 5μ long with slight terminal knob; tarsus 5μ long; tibia 3μ long.

Hindlegs 17μ long; feather-claw as above; claw bristle 7μ long with slight terminal knob; tarsus 5μ long; tibia 3μ long.

First thoracic setae about 3μ long directed anterolaterally. Second thoracic setae 9μ long, level with posterior edge of sternum. Third thoracic setae 18μ long, external to the second pair.

Abdomen with 50 tergites and 41 similar postgenital sternites. All but the last six rings with numerous, more or less circular, blunt micro-tubercles arranged in rows midway between anterior and posterior margins of rings. Lateral setae 15μ long on ring 7. First ventral setae 24μ long on ring 16. Second ventral setae 6μ long on ring 26 or 27. Third ventral setae 15μ long on about sixth ring from rear. Caudal setae about 45μ long. Two accessory caudal setae 3μ long located between and posterior to caudal setae.

Epigynium 17μ wide, 8μ long, saucer-shaped, located a moderate distance from the coxae. Coverflap with a single row of longitudinal striations, about 4 on each side. Genital setae 14μ long directed posteriorly. (Fig. 5.)

Type Locality: Waipara, Canterbury.

Collected: Galls collected by Miss P. A. Lush, June, 1949.

Relation to Host: Causes and dwells in stem galls.

Type Slide: So designated, with above data. In the collection of the Plant Diseases Division, Department, of Scientific and Industrial Research. Auckland. New Zealand.

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Family Leguminosae
Clianthus puniceus Banks and Sol.

7. Gall: Eriophyid witches’ brooms (Fig. 10).

Desription: The gall is about 10 cm. in diameter and is made up of a mass of witches' brooms composed of soft green branches bearing aborted, light green leaves, sometimes tinged with red. The whole originates from a single lateral branch which divides proximally into several slender twigs. Each of these gives rise to numerous short, slender, but fleshy shoots which bear leaves up to 7 mm. long and 2 mm. wide. Many of the branchlets ramify and all bear reddishtinged, terminal buds about 5 mm. in diameter.

Cause: Eriophyid mites and their eggs occur in large numbers—especially in the axils of the leaflets. The mite is described below as a new species.

Aceria clianthi sp.n.

Female: Length 225μ. Body vermiform, 58μ thick, 50μ wide. Rostrum 18μ long projecting forwards and curving slightly downwards. Thoracic shield triangular, 35μ long, 45μ wide.

Two dorsal shield setae 21μ long and 23μ apart located at hind margin of shield and pointing to rear.

Forelegs 27μ long; feather-claw 5μ long with 3 compound lateral rays and bifid tip; tarsus 3μ long; claw bristle 8μ long with a slight knob; tibia 5μ long without lateral spur. Hindlegs 25μ long; feather-claw as above; claw bristle 7·5μ long; tarsus 5μ long; tibia 6μ long.

First thoracic setae 4μ long directed inwards. Second thoracic setae 15μ long, directed outwards. Third thoracic setae 30μ long, directed outwards. The sternal ledge is level with the second thoracic setae.

Abdomen with 65–70 uniform tuberculate rings with more or less circular microtubercles located midway between the rings. The posterior 15 rings less heavily tuberculate. Lateral setae 26μ long located on ring 10. First ventral setae 38μ long located on the seventeenth postgenital ring. Second ventral setae 9μ long located on ring 33. Third ventral setae 24μ long located on the sixth ring from the rear. Caudal setae about 50μ long. Accessory caudal setae 4·5μ long, between and slightly posterior to caudal setae.

Genital coverflap with a single row of longitudinal striae, 4–6 on each side. Epigynium 23μ wide and 17μ long located a moderate distance from the coxae. Genital setae 14μ long. A prominent T-shaped genital apodeme is present, the cross-part located anterior to the coverflap. (Fig. 7.)

Male: Not studied.

Type Locality: Auckland, New Zealand.

Collected: September 16, 1949, Department of Agriculture.

Host: Clianthus puniceus Banks and Sol.

Relation to Host: Causes formation of fleshy, green witches’ brooms on stem.

Type Slide: So designated, with the above data. Located in the collection of the Plant Diseases Division, Department of Scientific and Industrial Research, Auckland, New Zealand.

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Fig. 1—Avicennia officinalis leaf crineum.
Fig. 4—Calystegia leaf pouch gall.
Fig. 6—Eriophyid leaf and bud galls on Nothofagus cliffortioides.

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Fig. 2—Aceria avicenniae sp.n.
Key to Drawings of Eriophyid Mites
D = dorsal shield
F = feather-claw
S = side view of mite
ES = detail of side skin
L = left legs
V = ventral view of mite
GF = female genitalia and coxae from below
GM = male genitalia and coxae from below

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Fig. 3—Vasates calystegiae sp.n.

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Fig. 5—Aceria carmichaeliae sp.n.

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Fig. 7—Aceria clianthi sp.n.

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Fig. 8—Eriophyes hoheriae sp.n.

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Fig. 9—Eriophyid gall on Carmichaelia subulate.
Fig. 10—Witches’ brooms on Clianthus puniceus.
Fig. 11—Hoheria populnea Eriophyid stem gall.
Fig. 14—Witches’ brooms on Leptospermum scoparium.

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Fig. 12—Aceria manukae sp.n.

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Fig. 13—Phyllocoptes coprosmae sp.n.

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Fig. 15—Eriophyid galls on Coprosma propinqua.
Fig. 16—Coprosma robusta leaf erineum.
Fig. 17—Caprosma robusta Eviophyid fruid gall. Photo. S. A. Rumsey.
Fig. 18—Vitex lucens leaf erineum.

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Fig. 19—Hebe salicifolia Cecidomyid stem galls
Fig. 20—Hebe salicifolia Coccid leaf galls.

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It may be observed that this mite is morphologically somewhat similar to Aceria carmichaeliae, though longer and with a larger number of abdominal rings. Undoubtedly the two species are closely related. However, the morphological differences and physiological differences demonstrated by the mites occurring on different plant genera and giving rise to galls of different structure are believed sufficient to warrant separation of the two species.

Family Malvaceae
Hoheria populnea A. Cunn.

8. Gall: Eriophyid stem gall. (Fig. 11.)

Description: Rough surfaced, dissected galls 1–2 cm. in diameter are borne laterally on the shoot, sessile or on a short stalk. Stellate and simple hairs are abundant. These galls originate as swellings of lateral buds and at maturity they probably represent a mass of fused aborted buds.

Cause: Eriophyid mites occur in small pockets and wrinkles in the surface of the gall. These galls are common and may occur in large numbers on a host plant.

The mite is described below as a new species, Eriophyes hoheriae.

Eriophyes hoheriae sp.n.

Female: 180μ long, vermiform in shape, tapering gradually posteriorly; 50μ wide, cylindrical in cross section. Rostrum 17μ long, curving downwards at an angle of 45 degrees.

Thoracic shield subtriangular, 44μ wide, 27μ long, with two distinct lateral striations on each side. A single pair of dorsal setae 18μ long and 18μ apart, slightly ahead of rear shield margin and directed anteriorly.

Forelegs 29μ long; feather-claw 4-rayed, 5μ long; claw bristle 8μ long with a distinct knob; tarsus 6μ long; tibia 6μ long. Hindlegs 24μ long; feather-claw and claw bristle as above; tarsus 6μ long; tibia 3μ long.

First thoracic setae indistinct, 8μ long. Second pair of thoracic setae 12μ long, internal, just ahead of posterior end of sternum. Third thoracic setae 30μ long, external to the second pair.

Abdomen with 63–70 tuberculate rings; the tubercles more or less diamond-shaped and slightly pointed. Lateral setae 15μ long on about ring 10. First ventral setae 20μ long on about ring 24. Second ventral setae 4μ long on about ring 43. Third ventral setae 17μ long on sixth ring from rear. Microtubercles not apparent on last six rings. Caudal setae about 45μ long. Accessory caudal setae present, 2μ long.

Epigynium 12μ wide, 15μ long; a moderate distance from coxae; cup-shaped. Coverflap smooth. Genital setae 5μ long. (Fig. 8.)

Male: Not studied.

Type Locality: Auckland.

Collected: Galls collected by C. S. W. Reid, September 9, 1940.

Host: Hoheria populnea A. Cunn.

Relation to Host: Causing and dwelling in stem galls.

Type Slide: So designated, with the above data. In the collection

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of the Plant Diseases Division, Department of Scientific and Industrial Research, Auckland, New Zealand.

Family Myrtaceae
Leptospermum scoparium Forst.

9. Gall: Eriophyid witches' brooms. (Fig. 14.)

Description: Witches' brooms in masses up to 6 cm. in diameter are found on the stem of this plant. They are composed of compact, hairy, brown coloured masses of buds on short twigs clustered about the stem. Eriophyid mites are found within the buds and these mites are described below as a new species (Aceria manukae).

Aceria manukae sp.n.

Female: 112μ long, 39μ wide, 30μ thick, white in colour, spindle-shaped, tapering gradually towards the anal end. Rostrum 13μ long, pointing ahead. Thoracic shield 23μ long, 38μ wide, triangular in shape with 6 major longitudinal striations and lateral granulation. Dorsal setae 15μ long, situated at rear margin of shield 18μ apart and pointing to the rear.

Forelegs 21μ long; feather-claw 4-rayed, 5μ long; claw bristle about 6μ long with a knob; fifth joint indistinctly divided into two, 5μ long; tibia 3μ long, without lateral setae. Hindlegs 21μ long; feather-claw as above; tarsus 3μ long; tibia 3μ long.

First pair of thoracic setae 2μ long, very slender; second pair of thoracic setae 3μ long, level with rear of sternum; third pair of thoracic setae 25μ long, directed anterolaterally.

Abdominal rings 55–60 in number, entirely tuberculate, the tubercles oval, not pointed and arranged along the rear edges of the rings. Subdorsal abdominal setae absent. Lateral setae 23μ long on about ring 6. First ventral setae 38μ long, with distinct tubercles on about ring 13. Second ventral setae 3μ long, indistinct, on about ring 28. Third ventral setae 25μ long, with distinct tubercles on sixth ring from rear. Caudal setae about 48μ long.

Epigynium a moderate distance from coxae, saucer-shaped, 17μ wide, 10μ long. Coverflap with a single row of longitudinal striae, 5 on each side. Genital setae 6μ long, directed backwards. (Fig. 12.)

Male: Not studied.

Type Locality: Whakatane, New Zealand.

Collected: July 29, 1949, by Miss M. Simpson.

Host: Leptospermum scoparium Forst. (“Manuka”).

Relation to Host: Causing witches’ brooms on stem.

Type Slide: So designated, with the above data. In the collection of the Plant Diseases Division, Department of Scientific and Industrial Research, Auckland, New Zealand.

Family Polygonaceae

Muehlenbeckia axillaris Walp.

10. Gall: Eriophyid leaf pouch gall.

Description: The galls are of the usual pouch type and are 1–2 mm. in diameter. They are bright red in colour, but are rather inconspicu-

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ous owing to their small size. A few orange coloured Eriophyid mites of the genus Eriophyes occur in each gall. The mites are probably of an undescribed species, but further material is required for description. The gall is described from M. axillaris growing in turf by the shore of Lake Taylor, South Island, collected in November, 1948, by Miss A. Lush.

Family Rubiaceae
Coprosma parviflora Hook. f.

11. A complex of galls occurs on plants of the C. parviflora group and these require further study. However, the following gall represents a common type.

Gall: Eriophyid stem gall.

Description: Rough, sessile, globose or flattened galls 7–8 mm. in diameter are borne laterally on the shoot. The galls are grey in colour. Eriophyid mites are present within the galls.

This was described from material in the Plant Diseases Division herbarium, collected by E. D. Hatch at National Park on June 2, 1943.

Cause: The eriophyid mite, Aceria cottieri, which is described below from C. robusta.

Coprosma propinqua A. Cunn.

12. A gall of similar appearance to the one described above on C. parviflora was collected on C. propinqua at Kaihere, Auckland, by J. Hoy on July 13, 1949. (Fig. 15.) Eriophyid mites of the subfamily Eriophyinae were present. Further material is required for species determination.

Coprosma australis (A. Rich.) Robinson

Coprosma robusta Raoul

13. Gall: Leaf erineum (Fig. 16).

Description: Rather thin erineum is often found in oval or irregular patches extending over the greater part of the abaxial leaf surface. It is white when fresh, but later becomes brown. Eriophyid mites are responsible for erineum formation, and these are described below from C. robusta as a new species (Phyllocoptes coprosmae).

This gall has been collected by the writer on C. robusta in the Bay of Islands, January, 1949; Titirangi, July and August, 1949. C. australis material was collected at Titirangi by Miss E. Bray in August, 1949.

Phyllocoptes coprosmae sp.n.

Female: 180μ long, 57μ thick, spindle shaped and tapering posteriorly. Rostrum 23μ long, at right angles to body. Thoracic shield 38μ long, 45μ wide, with a median striation, two major sub-median longitudinal striations and several sinuate lateral striations. The posterior margin of the shield somewhat sinuate. Short anterior lobe overhanging rostrum. Two dorsal setae 30μ long and 23μ apart, located in front of rear shield margin and pointing upwards.

Forelegs 27μ long; feather-claw 5μ long with 4 compound lateral rays; claw bristle 8μ long with a slight knob; tarsus 6μ long; tibia 6μ

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long. Hindlegs 23μ long; feather-claw and claw bristle as above; tarsus 5μ long; tibia 4μ long.

Thoracic seta I, 1·5μ long. Thoracic seta II, 8μ long. Thoracic seta III, 18μ long.

Abdomen with 40 tergites with smooth, elongated blunt micro-tubercles. Tergites larger than sternites. Forty-six postgenital sternites with pointed circular microtubercles. Lateral setae 15μ long, located on ring 6. First ventral setae 38μ long, located on ring 18. Second ventral setae 14μ long, located on ring 32. Third ventral setae 15μ long, located on about the fourth ring from rear. Caudal setae about 60μ long. Accessory caudal setae present, 3μ long.

Epigynium 21μ wide, 12μ long, cup-shaped, located a moderate distance from the coxae. Coverflap irregularly sculptured with approximately two rows of longitudinal striations and some anterior lateral striations. Genital setae 17μ long, directed caudad. (Fig. 13.)

Male: Not studied.

Type Locality: Auckland.

Collected: Galls collected by Miss E. Bray.

Host: Coprosma robusta Raoul.

Relation to Host: Causing leaf erineum.

Type Slide: So designated with the above data. Located in the collection of the Plant Diseases Division, Department of Scientific and Industrial Research, Auckland, New Zealand.

Family Rubiaceae
Coprosma robusta Raoul

14. Gall: Eriophyid fruit gall. (Fig. 17.)

Description: Proliferation of the pericarp and outer tissues of the fruit results in the formation of discrete, grooved galls each about 5 mm. in diameter. They are pale green in colour tinged with red. Advanced galls cease to resemble fruit, though early stages may be seen where a single drupe bears a mass of proliferating tissue on one side. The individual galls are sometimes packed close together in bunches up to 2 cm. in diameter.

Cause: Eriophyid mites are responsible for gall formation. Tarsonemid mites (Tarsonemus sp.) have been found associated with them. The causal eriophyid is described below as a new species (Aceria cottieri). It is also found in stem galls of C. parviflora, but is distinct from the mite causing the erineum on C. robusta.

Aceria cottieri sp.n.

Female: 160μ long, 39μ wide, 38μ thick, vermiform, tapering posteriorly. Rostrum 18μ long, curving down at the same angle as the shield. Thoracic shield with lateral granulation, subtriangular, 32μ wide, 20μ long, with two dorsal setae 20μ long and 23μ apart, located on the rear margin of the shield and directed posteriorly.

Forelegs 17μ long; feather-claw 5μ long, very slender and with four lateral rays; claw bristle 6μ long, lacking a distinct knob; tarsus 2μ long; tibia 1·5μ long.

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Hindlegs 14μ long; feather-claw and claw bristle as above; tarsus 3μ long; tibia 1·5μ long.

Thoracic setae I, 1·5μ long, directly ahead of II. Thoracic setae II, 8μ long. Thoracic setae III, 17μ long, external to I and II.

Abdomen with about 50 tergites with oval microtubercles, and 48 postgenital sternites similar to the tergites. Lateral setae 12μ long, located on ring 7 or 8. First ventral setae 24μ long on about ring 17. Second ventral setae 17μ long on ring 32 or 33. Third ventral setae 13μ long on 6th ring from rear. Caudal setae about 38μ long.

Epigynium bowl-shaped, 18μ wide, 12μ long, located a moderate distance from the coxae. Coverflap with a single row of longitudinal striations, about 3 or 4 on each side. Genital setae 6μ long, directed caudad.

Type Locality: Auckland.

Collected: At Purewa, Auckland, by D. McKenzie, June, 1949.

Host: Coprosma robusta Raoul.

Relation to Host: Causing galls on fruit.

Type Slide: So designated, with the above data. Located in the collection of the Plant Diseases Division, Department of Scientific and Industrial Research, Auckland, New Zealand.

Family Verbenaceae Vitex lucens. Kirk

15. Gall: Leaf erineum. (Fig. 18.)

Description: White or brown pile on the abaxial leaf surface forms oval spots 2–20 mm. in diameter and about 1 mm. high. This gall is described from fresh material collected at Titirangi in August, 1949, by Miss E. Bray. Material in the Plant Diseases Division herbarium was collected at Tauranga by I. Nottage in September, 1939.

A new species of mite (Aceria australis) described below is responsible for gall formation.

Aceria australis sp.n.

Female: 135μ long, 38μ wide, 38μ thick, vermiform, tapering posteriorly. Rostrum 15μ long, curving down. Thoracic shield sub-triangular, 30μ wide, 21μ long; with a median longitudinal striation, two submedian striations extending the length of the shield, then one on each side extending halfway down the shield from the anterior margin. Two short lateral striae on each side. Two dorsal shield setae 18μ long and 18μ apart located on the rear margin of the shield and directed posteriorly.

Forelegs 17μ long; feather-claw 4·5μ long with 3 compound lateral rays and a bifid tip; claw bristle 6μ long with a very small knob; tarsus 6μ long; tibia 3μ long.

Hindlegs 18μ long; feather-claw as above; claw bristle 7μ long; tarsus 4·5 long; tibia 3μ long.

First thoracic setae 3μ long, slender. Second thoracic setae 10μ long. Third thoracic setae 17μ long.

Abdomen with 70 tergites and 50 similar, postgenital sternites; each with oval, blunt microtubercles adjacent to the posterior margin

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of each ring. Lateral setae 7·5μ long located on ring 8. First ventral setae 11μ long located on ring 19 or 20. Second ventral setae 3μ long located on ring 34 or 35. Third ventral setae 11μ long on the sixth ring from the rear. Caudal setae about 30μ long. No accessory caudal setae.

Epigynium cup-shaped, 18μ wide and 14μ long, with a single row of longitudinal striations—about 4 on each side. Genital setae 4·5μ long directed caudad.

Male: Not studied.

Type Locality: Auckland.

Collected: By Miss E. Bray, August 26, 1949.

Host: Vitex lucens Kirk.

Relation to Host: Causing erineum on leaves.

Type Slide: So designated, with the above data. Located in the collection of the Plant Diseases Division, Department of Scientific and Industrial Research, Auckland, New Zealand.

B. Galls Caused by Insects
Family Scrophulariaceae

Hebe salicifolia Forst.

16. Gall: Cecidomyid stem gall: (Fig. 19.)

Morphology: Mature galls are smooth, more or less cylindrical or globose, fleshy stem swellings usually 0·5 to 2 cm. thick by 1·5 to 2·5 cm. long. Immature galls lack any holes, but few to many exit holes may be seen on mature or old galls.

Cause: Cecidomyid midges are responsible for this gall. Numerous small white larvae with an anteriorly bifid sternal process occur in individual cavities in immature galls. They feed extensively and in a heavy infestation they may eat a considerable part of the inside of the gall. In such cases their individual tunnels eventually join. Pupation occurs within the gall and adults emerge through exit holes in the sides of the gall. Pupal cases are often left hanging from exit holes. The species is different from that which forms leaf galls on the same plant species, but insufficient material is available for its description.

Occurrence: Specimens have been collected by the writer as follows: Rangitoto Island, April, 1948; June, 1949. Christchurch, November. 1948.

Family Scrophulariaceae

Hebe salicifolia Forst.

17. Gall: Coccid dimple gall. (Fig. 20.)

Morphology: The galls are simply deep depressions in the abaxial surface of the leaf. The opening of the depression is about 1 to 2·5 mm. wide and has a slightly upraised rim. On the adaxial surface the galls appear as conical elevations about 3 mm. high. Towards the apex the elevations are frequently reddish brown in colour.

Cause: A scale insect, Rhizococcus fossor Mask. is responsible for gall formation, Adult females, usually swollen with embryos, occupy

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almost the whole of the gall cavity. They may be seen from the abaxial surface as oval, yellow or brown objects with two small, brown, chitinized anal tubercles. When this insect was described by Maskell (1883), he gave its sole host plant as maire (Fusanus cunninghamii Benth. and Hook.), and described the insects’ mode of burrowing into the leaf as unique among the Coccidae. This therefore constitutes a new host record.

Occurrence: On Hebe salicifolia Forst. growing in the grounds of Victoria University College, Wellington, July, 1948.

Family Saxifragaceae

Carpodetus serratus Forst.

18. Gall: Solid stem, leaf, petiole or fruit gall. Commonly occurring on side shoots.

Morphology: The galls occur on all aerial parts of the plant, but they are most frequent on slender twigs, where they appear as oval, more or less smooth swellings. The long axis of the gall may lie along the axis of the twig, but often the gall is terminal and rotated at an angle to the twig. Mature galls are 1·5 to 2 cm. long and 1 to 1·5 cm. thick. They are covered with the normal smooth, grey, lightly pubescent bark with occasional brown lenticels. Usually the galls are simple and solitary, each containing a single insect; but sometimes two or four are fused together, each lobe containing a separate larva. A single, small exit hole is found in mature galls, usually at or near the proximal end of the gall. Developing galls have no exit holes.

Cause: Each gall contains a single white or cream coloured gallmidge larva (Family: Cecidomyidae). The young larva is found about the centre of the gall and as it develops it eats out a smooth sausage-shaped tunnel. By the time the larva is mature the tunnel reaches the end of the gall. Larvae remain active throughout the winter.

Some galls obtained in May, 1949, from the Waitakere Ranges contained sluggish and moribund Cecidomyid larvae with small ecto-parasitic larvae feeding on them. A single parasite was found in each infested gall.

The gall midge has not yet been identified.

Occurrence: Common throughout New Zealand wherever the host plant is found. However, in any particular region, gall-bearing plants tend to occur in clusters. Thus a considerable area of Carpodetus may be uninfested, though a few hundred yards away a local but quite heavy infestation may occur.

Family Leguminosae

Carmichaelia australis R. Br.

19. Gall: Cecidomyid cladode gall.

Description: Irregular but smooth swelling of the cladodes, 0·5μ to 1·5 cm. long and 3 mm. thick. One to several small round exit holes were found on mature galls, and within the galls were a number of orange-coloured Cecidomyid larvae with anteriorly bifid, sternal shields. Adults were not reared.

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This material was collected at Titirangi, Auckland, in May, 1949, by Miss J. Hastings.

Acknowledgments

I wish to acknowledge with thanks advice on Eriophyid technique from Dr. A. M. Massee, of Rothamsted Experimental Station, and Dr. W. Cottier, of the Plant Diseases Division, Department of Scientific and Industrial Research. Thanks are also offered to the many people whose assistance in the collection of material has made this work possible.

This work was commenced in the Botany Department, Auckland University College, and part was submitted in a thesis for the M.Sc. degree.

All photographs are by the author unless otherwise acknowledged.

Literature Cited

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Barnes, H. F., 1946. Gall Midges of Economic Importance. Root and Vegetable Crops, vol. 1, 104 pp. London.

Baylis, G. T. S., 1940. Leaf Anatomy of the N.Z. Mangrove. Trans. Roy. Soc. N.Z., 70, 164–170.

Docters van Leeuwen-Reijnvaan, J., and Docters van Leeuwen, W. M., 1926. The zoocecidia of the Netherland East Indies, 601 pp. Batavia.

Houard, C., 1923. Les zoocécidies des plantes d'Afrique, d'Asie et d'Océanie, vol. 2, pp. 1056. Paris.

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Nalepa, A., 1906. Ueber das Praeparieren und Konservieren der Gallmilben. Marcellia, 5, 59–61.

Rübsaamen, E. H., 1911. Die Zoocecidien, durch Tiere erzeugte Pflanzengallen Deutschlands und ihre Bewohner. Zoologica, 61.

Stewart and Freeborn, 1937. U.C. Agr. Ewpt. Sta. Bul., 603, p. 6.

Swanton, E. W., 1912. British Plant Galls. London.