# Black Locust Leafminer (*Macrosaccus robiniella*)

The Black Locust Leafminer is a tiny insect that loves to munch on the leaves of black locust trees. It makes little tunnels inside the leaves, which can look like tiny mazes!

- **Category:** [Insects](https://www.snappit.app/explore/categories/insect)
- **Rarity:** Common
- **Danger:** 1/5 · Very low
- **Habitat:** Forests

![Black Locust Leafminer](https://commons.wikimedia.org/w/index.php?title=Special:Redirect/file/Macrosaccus_robiniella_lateral_Bytom.jpg&width=800)

Photo: Adrian Tync, CC BY-SA 4.0 · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Macrosaccus_robiniella_lateral_Bytom.jpg)

## Appearance

The Black Locust Leafminer is a tiny moth, usually 3-5mm long, with silvery-white forewings adorned with dark spots and a coppery sheen. Its hindwings are slender and heavily fringed. This distinct pattern helps distinguish it from other small moths.

## Taxonomy

- **Kingdom:** Animalia
- **Phylum:** Arthropoda
- **Class:** Insecta
- **Order:** Lepidoptera
- **Family:** Gracillariidae
- **Genus:** Macrosaccus

## Interesting facts

- Did you know leafminer larvae live their whole lives \*inside\* a leaf? Wow!
- Some black locust trees can host hundreds of these tiny leafminers at once!
- The adult moths are so small, you might mistake them for a speck of dust!
- They create winding "galleries" inside leaves, like tiny secret tunnels!

## Special abilities

- **Leaf Tunnel Architect:** Black Locust Leafminers can chew tunnels inside leaves because it helps them stay hidden from predators and eat safely.
- **Invisible Gardener:** Larvae have flat, pale bodies that help them blend perfectly with the inside of a leaf, making them hard to spot.
- **Toxic Taste Tester:** Black Locust Leafminers can digest the tough and slightly toxic leaves of black locust trees that many other insects avoid.

## Measurements & details

- **Wingspan:** 4-7 mm
- **Size:** 3-5 mm
- **Lifespan:** 30-60 days
- **Leg Count:** 6

## Diet & Feeding

These tiny insects munch on the soft parts of black locust leaves as larvae.

- **Age differences:** Larvae feed exclusively on leaves; adults do not feed or consume very little nectar.
- **Primary Foods:** Black Locust Leaves
- **Foraging Method:** Foraging

## Ecological connections

- **Eats:** Black Locust Tree (*Robinia pseudoacacia*) — Larvae feed inside the leaves of this tree.
- **Parasitizes:** Parasitic Wasp (*Pnigalio flavipes*) — Larvae are often parasitized by tiny wasps.
- **Eaten by:** [Black-capped Chickadee](https://www.snappit.app/explore/black-capped-chickadee) (*Poecile atricapillus*) — Small birds often pluck them from leaves.

## Traits

- [Solitary](https://www.snappit.app/explore/traits/solitary): Solitary animals live alone for most of their lives, only interacting with others for mating or parental care.
- [Herbivorous](https://www.snappit.app/explore/traits/herbivorous): This trait characterizes organisms whose diet consists entirely or primarily of plant material.
- [Forest](https://www.snappit.app/explore/traits/forest): Forest habitats are terrestrial environments dominated by dense tree cover, supporting a high diversity of plant and animal life.
- [Miniature](https://www.snappit.app/explore/traits/miniature): Pertaining to species that are significantly smaller than typical or average for their kind.

## Collections

- [Insects](https://www.snappit.app/explore/collections/insects)

## Safety

**Danger:** 1/5 · Very low

It's best to look at insects from a distance and not touch them, as they can be delicate.

## Frequently Asked Questions

### How to identify Black Locust Leafminer?

Compare resting wing shape, forewing markings, antennae and body build. Small brown moths can hinge on fine details a phone photo can't always catch. Moth Identifier: upload a photo and compare the visible details.

### What is Black Locust Leafminer's wingspan?

4-7 mm

### How big is Black Locust Leafminer?

3-5 mm

### How long does Black Locust Leafminer live?

30-60 days

### What does Black Locust Leafminer eat?

These tiny insects munch on the soft parts of black locust leaves as larvae.

### Where is Black Locust Leafminer usually found?

Forests

### How does Black Locust Leafminer hunt?

Foraging

### How many legs does Black Locust Leafminer have?

6

## Where to spot

- [Bear Creek Provincial Park](https://www.snappit.app/guides/places/bear-creek-provincial-park) — British Columbia, CA · State Park

## More Insects

- [Common Eastern Bumble Bee](https://www.snappit.app/explore/common-eastern-bumble-bee) (*Bombus impatiens*)
- [Spotted Lanternfly](https://www.snappit.app/explore/spotted-lanternfly) (*Lycorma delicatula*)
- [Brown-belted Bumble Bee](https://www.snappit.app/explore/brown-belted-bumble-bee) (*Bombus griseocollis*)
- [Eastern Carpenter Bee](https://www.snappit.app/explore/eastern-carpenter-bee) (*Xylocopa virginica*)

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Source: [Black Locust Leafminer: Facts & Places to See — Snappit](https://www.snappit.app/explore/black-locust-leafminer)