Blackthorn - Prunus spinosa

Parornix torquillella

The larva of the moth Parornix torquillella mines the leaves of Blackthorn and Wild Plum. The initial mine is a blotch type. It then leaves this and makes folds on the leaf edge. The larval foodplant, Blackthorn is shared with the similar Parornix finitimella and the mines cannot be distinguished unless larvae are examined.  Parornix finitimella is greyish with black rings on the legs, whereas Parornix torquillella is usually pale green with concolorous legs.

Pistol Case-bearer

The cased larva of the moth Coleophora anatipennella feeds on Blackthorn as well as other species such as Hawthorn and Apple. It is sometimes called a Pistol Case-bearer, so named from the resemblance of the larval case to an old flintlock pistol in shape.

Coleophora violacea

The cased larva of the moth Coleophora violacea feeds on Blackthorn as well as a wide range of trees, shrubs and herbs. The larval cases are about 6 mm long. The dorsal surface of the case is usually covered in leaf fragments, but they can sometimes be worn off almost smooth. The ventral surface is swollen at the middle and has a keel, which usually bends upwards at the posterior.

Hawthorn Moth

The larvae of the moth Scythropia crataegella feed communally in a silken web spun on Hawthorn after initially mining the leaves. Other foodplants include Blackthorn and Cotoneaster.

Pocket Plum

Taphrina pruni is a fungal plant pathogen that gives rise to the Pocket Plum or Bladder Plum gall.  The fruit is swollen and deformed. Affected fruits have no stone.  The shoots may also be swollen and stunted, and reddish or yellowed. 

Eriophyes similis

The mite Eriophyes similis causes galls to form on the leaves of Prunus species, usually Blackthorn, but also on plums and damsons. The galls are elongated ovals, usually heaviest around the leaf margins.  The galls are usually with a large protrusion on the underside the leaf and a smaller protrusion with an elongated slit opening on the upperside.  However they can be found in a reversed position with the larger protrusion on the upperside.   

Eriophyes homophyllus

The gall mite Eriophyes homophyllus produces rounded hairy galls on Blackthorn and Plums/Damsons/Bullace etc. (Prunus domestica). The galls are found mainly along the midrib on the leaf upperside.  There is small hairy opening o nthe leaf underside.   The galls are often flushed pink.

Putoniella pruni

The larva of the gall midge Putoniella pruni causes a gall on Blackthorn and other Prunus species. The galls ca be found in 2 types: as a swelling on the midrib underneath, often reddish, with a slit-like opening above; or a hard, upward-rolled, pod-like leaf margin.  The larvae are orange.  

Lyonetia prunifoliella

The larva of the moth  Lyonetia prunifoliella mines the leaves of Blackthorn. The mine is a narrow gallery leading to a clear blotch. Strings of black frass hang beneath the blotches. 

Pristiphora monogyniae

The larva of the sawfly Pristiphora monogyniae feed on Blackthorn and cause a downward leaf roll gall on the leaves.

Parornix finitimella

The larva of the moth Parornix finitimella mines the leaves of Blackthorn.  The mine is initially a lower epidermal gallery leading to a grey or whitish blotch which contorts the leaf strongly. Then at least two folds on the leaf margin, consuming the upper epidermis. The larval foodplant, Blackthorn is shared with the similar Parornix torquillella and the mines cannot be distinguished unless larvae are examined.  Parornix finitimella is greyish with black rings on the legs, whereas Parornix torquillella is usually pale green with concolorous legs.

Phyllonorycter spinicolella

The larva of the moth Phyllonorycter spinicolella mines the leaves of Blackthorn. The mines are narrow and cause the leaf to pucker strongly, often folding right over, and being whitish can resemble those of the blackthorn-feeding Parornix species. 

Stigmella plagicolella

The larva of the moth Stigmella plagicolella mines the leaves of Blackthorn creating a roundish blotch which begins as a narrow gallery and often ends up looking rather like a tadpole in shape.

Apple Leaf Miner

The Apple Leaf Miner (Lyonetia clerkella) is a tiny moth (wingspan 7 to 9 mm) with a silvery appearance but very attractively patterned when seen under magnification. 

The larva produces a leafmine on a number of species, especially Cherry, Apple, Rowan, Hawthorn, Blackthorn and other trees and shrubs in the Rosaceae family.  It is also commonly found on Birch. The mine is long smoothly curved gallery with frass in a central line; older mines look whitish. The larva is long and slender. It has a segmented body and 6 dark feet.

Water Lily Aphid

The primary host for the Water Lily Aphid (Rhopalosiphum nymphaeae) are Prunus species such as Blackthorn and Plum. On these primary host species the apterae are reddish-brown. On Water-lily, the secondary host they may be shiny reddish-brown to dark olive. The Alates are shining brown, sometimes with white dorsal wax markings. The Rhopalosiphum nymphaeae aptera body length is 1.6 to 2.6 mm.

Damson-hop aphid

The Damson-hop Aphid (Phorodon humuli) host alternates from Blackthorn or Plum species (Prunaceae) to Hops. Phorodon humuli apterae are small to medium sized, whitish to pale yellowish green and relatively shiny. The abdomen is marked with three dark green longitudinal stripes.

Brachycaudus helichrysi

Brachycaudus helichrysi aphids causes distortion of leaves of various Prunus species including Blackthorn, causing the leaves to become rolled up tightly in spring.  These are not true galls, and other aphids may cause similar leaf distortions. The aphids are about 2 mm, greenish, yellowish or brownish, somewhat waxy; siphunculi very short; antennae shorter than the body with a darkened tip.