35.073 Monochroa palustrellus (Douglas, 1850)

Status and Distribution

Local, occasionally locally common, in southern and eastern England. Around the start of the 21st Century the moth started expanding its range northwards and westwards, with records from Lincolnshire and Nottinghamshire, to the north and Dorset, Gloucestershire, Glamorgan, Monmouthshire, Somerset and Wiltshire to the west. In 2019 it was noted for the first time in North Devon. There is a single record of one in Co. Clare, Ireland in 2006.

 

National Status: Nationally Scarce B
Bradley & Fletcher no: 737
Photographer: © C Manley
Location: Kent

Provisional map

NHMSYS0000503279

Larva

 Monochroa palustrellus larva Kent Rumex hydrolapathum 2023 (Photo: © W Langdon)  Monochroa palustrellus larva Kent Rumex hydrolapathum 2023 (Photo © W Langdon)

Pupa

Set Specimens

Monochroa palustrellus courtesy BENHS (Photo: © S Palmer)

Foodplant and Larval Feeding Signs

Monochroa palustrellus larval feeding Rumex hydrolapathum Kent  2023 (Photo: © W Langdon)   Monochroa palustrellus larval feeding Rumex hydrolapathum Kent  2023 (Photo: © W Langdon)  Monochroa palustrellus larval feeding sign Rumex hydrolapathum Kent  2023 (Photo © W Langdon)  Monochroa palustrellus larval feeding Rumex hydrolapathum Kent  2023 (Photo: © W Langdon)

Rumex crispus (curled dock), see plant distribution map, and possibly sometimes on other Rumex spp.

In Europe also found on Rumex aquaticus and Rumex hydrolapathum.

The larva feeds internally in the roots, stem or leaf petioles with no external signs of occupation.

Habitat

Monochroa palustrellus larval habitat Kent 2023 (Photo: © W Langdon)

Waste ground, roadsides, disturbed dry pastures and sand dunes.

Finding the Moth

Larva: within the rootstock, stem or leaf petioles from April to June, pupation taking place in the rootstock during June and July although latest flight period data suggests the possibility of these processes occuring earlier in the year or maybe even a second brood.

Adult: flies at night and comes regularly to light traps where most records of this species originate.

Similar Species

Its large size, fully upturned palps and streaked forewing with pale ringed black marks make this a distinctive and easily recognised species.

Ypsolopha ustella is of a similar size and shape and one form, a strongly cream and brown streaked looking moth with a black dot in the centre of the wing at three quarters, can be superficially similar. Y. ustella lacks the pointed finger-like projection on the hindwing, the black dot at three-quarters lacks a white surround and the central eye-shaped blackish marking and pale surround found in M. palustrellus are absent from the forewing of Y. ustella.

May, June, July
June, July, August, September, October

Mainly single brooded from mid-June to mid-August. However, from as far back as 1955 and 1976, and almost annually since 2006, the moth has been found in September with a few into October over parts of its range in an apparent small second brood. The latter includes a very late one on 17th October 2024 in Kent.