Geometridae : Larentiinae
  Prev | Next  
Photo © Graham Geen,  Mundford - 19/05/2020 - Possible candidate (Unconfirmed)

Similar Norfolk Species
Horisme tersata
Upload a Photo
Cryptic Fern
Horisme radicaria

(La Harpe, 1855) 1782a / 70.1271

Norfolk status
No confirmed Norfolk records.

The Fern Horisme tersata, has now (2019) been split in to two species in the UK. The new Cryptic Fern Horisme radicaria appears to have been hiding in plain sight for a number of years in Britain, with evidence from Europe suggesting that it is a recent/current colonist rather than a long-overlooked resident. Extremely hard to separate and dissection required to confirm any potential specimens.

Cryptic Fern has to date been confirmed on only a few occasions, the most recent being May 2020 in Kent.

Although dissection required, Cryptic Fern is noted in some specimens as lacking the dark discal spot of Fern and having a more pronounced clear black apical streak. [Ent. Rec. 131 (2019)] Cryptic Fern also appears to be on the wing a few weeks earlier then Fern in May. Please retain any potential specimens for determination. (Contact Jon Clifton)

A photograph, thought at the time to be of a Fern, taken at Mundford on 19 May 2020 (G. Geen) was recently submitted as a possible candidate. Although it is not possible to confirm from photo only, it does look like a possible Cryptic Fern, and it is now certainly worth checking and retaining any unusual specimens of Fern, as this species may be present in Norfolk. JW

Determination by Genitalia Examination (gen. det.) Required

Additional Stats

< Fern | Pretty Chalk Carpet >

Comparison of male Horisme sp. J. Clifton.
List Species Records   [Show All Latest]
Latest 5 Records
Date#VC10kGeneral Area
Show Details | 1990 to 2023 | 2000 to 2023 | Graph Key
Express Record Cryptic Fern
We need your records!
Do you have records of Cryptic Fern?
Put your own dot on the map!

Copyright © Lepidoptera UK 2024
Click Map for Details

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Forewing: 14-18mm
Flight: May - July ?
Foodplant:   in Europe Traveller's-joy
Former Status: Unknown
Verification Grade:  Adult: 4
 Immature Adult   [Show Flight Times]

Data Policy | Cookies Policy
Underlying maps using Digital Map Data © NOLA™ 2024. © Lepidoptera UK - Jim Wheeler - Norfolk Moths 2007 - 2024. Data © NOLA™ 2024
This site requires necessary cookies to function correctly. We'd also like to set Google analytics cookies that help us make improvements by measuring how you use the site. These will be set only if you accept all cookies. Necessary cookies enable core functionality such as security, network management, and accessibility. You may disable these by changing your browser settings, but this will affect how the website functions. Cookies Policy