Rectiostoma fernaldella
(Riley, 1889)
Stenomid Oak Leaf Tier
A small in the Depressariidae, described by Riley in 1889. are active in shady oak during midday and have a single in California. Larvae are specialized leaf tiers that construct distinctive -sealed shelters between two leaves.
Pronunciation
How to pronounce Rectiostoma fernaldella: /rɛk.ti.oʊˈstoʊ.mə fərˈnɔːldˌɛl.ə/
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
Distinguished by its extremely small size (wingspan ~13 mm) and association with oak leaf tier shelters. The larval shelters are diagnostic: two leaves sandwiched with a thick, conspicuous rim of and silk. fly in shady areas under oaks during midday, a behavioral cue that may aid detection. Disjunct distribution pattern (Arizona/California/Tennessee) is notable.
Appearance
Small with a wingspan of approximately 13 mm. Detailed coloration and pattern not described in available sources. Larvae construct visible shelters consisting of two leaves pressed together with a thick rim of and silk sealing the edges.
Habitat
Shaded areas under oak trees. Larval consists of living oak foliage where leaf-tier shelters are constructed.
Distribution
North America from southern Mexico to the United States. In the U.S., found in the eastern basin and range area of southern Arizona, disjunctly in California, and with a single record from Tennessee.
Seasonality
Single in California with on wing May through July. Adults observed flying during midday.
Diet
Larvae feed on multiple oak : Quercus agrifolia, Quercus wislizenii, Quercus dumosa, Quercus dumosa × engelmanni, Quercus lobata, Quercus suber, Quercus chrysolepis, Quercus dunii, and also Lithocarpus densiflorus, Chrysolepis chrysophylla, and Chrysolepis sempervirens. : diet not documented.
Host Associations
- Quercus agrifolia - larval food plantcoast live oak
- Quercus wislizenii - larval food plantinterior live oak
- Quercus dumosa - larval food plantcoastal sage scrub oak
- Quercus lobata - larval food plantvalley oak
- Quercus suber - larval food plantcork oak
- Quercus chrysolepis - larval food plantcanyon live oak
- Quercus dunii - larval food plantDunn's oak
- Lithocarpus densiflorus - larval food planttanoak
- Chrysolepis chrysophylla - larval food plantgiant chinquapin
- Chrysolepis sempervirens - larval food plantbush chinquapin
Life Cycle
Single in California. Larvae overwinter within shelters constructed by the preceding generation. These shelters consist of two leaves sandwiched together with a thick rim of and silk sealing the edges. Within shelters, larvae skeletonize both leaf surfaces.
Behavior
fly in shady areas under oaks during midday. Larvae construct and occupy leaf-tier shelters, reusing shelters from previous for . Within shelters, larvae skeletonize both surfaces of the enclosed leaves.
Ecological Role
Leaf-tier herbivore that skeletonizes oak foliage. Shelter construction creates distinctive microhabitats that may influence local leaf litter dynamics.
Similar Taxa
- Other Rectiostoma speciesSimilar small size and leaf-tying ; precise identification requires examination of genitalia or molecular data
- Other Stenomatinae (Depressariidae)Shared leaf-tier larval habit; distinguished by specificity, shelter construction details, and geographic distribution
More Details
Shelter reuse
Larvae utilize shelters made by the preceding for , indicating a multi-generational use of individual shelter structures.
Hybrid oak host
Recorded from Quercus dumosa × engelmanni, indicating use of hybrid oaks.