Butterflies and Moths of San Mateo County

179 Species Recorded in San Mateo County

Top 20 Species Checklist All Photographs

100 Most Recent Sightings in San Mateo County

Use the Data Explorer to explore all sightings in San Mateo County.

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Most Recent Sightings in San Mateo County

See more recent sightings in San Mateo County

Coenonympha california

Observed: Oct 10, 2025

Submitted by: Sophia Reyes

Verified: Oct 13, 2025

Verified by: Ken Davenport

Details

Common Checkered-Skipper
Burnsius communis

Observed: Oct 10, 2025

Submitted by: Sophia Reyes

Verified: Oct 13, 2025

Verified by: Ken Davenport

Details

Field Crescent
Phyciodes pulchella

Observed: Aug 31, 2025

Submitted by: Sophia Reyes

Verified: Sep 08, 2025

Verified by: Ken Davenport

Details

California Sister
Adelpha californica

Observed: Jul 29, 2025

Submitted by: Karen Richardson

Verified: Aug 01, 2025

Verified by: Ken Davenport

Details

Cabbage White
Pieris rapae

Observed: Jul 25, 2025

Submitted by: Sophia Reyes

Verified: Jul 27, 2025

Verified by: Ken Davenport

Details

Small Checkered-Skipper
Pyrgus scriptura

Observed: Jul 21, 2025

Submitted by: Sophia Reyes

Verified: Jul 25, 2025

Verified by: Ken Davenport

Details

Digrammia delectata

Observed: Jul 17, 2025

Submitted by: docentgal

Verified: Nov 16, 2025

Verified by: jwileyrains

Details

Gray Buckeye
Junonia grisea

Observed: Jul 13, 2025

Submitted by: Guy Albertelli

Verified: Jul 14, 2025

Verified by: Ken Davenport

Details

Anise Swallowtail
Papilio zelicaon

Observed: Jul 04, 2025

Submitted by: Sophia Reyes

Verified: Jul 06, 2025

Verified by: Ken Davenport

Details

Field Crescent
Phyciodes pulchella

Observed: Jul 04, 2025

Submitted by: Sophia Reyes

Verified: Jul 06, 2025

Verified by: Ken Davenport

Details

Echo Azure
Celastrina echo

Observed: Jun 30, 2025

Submitted by: Sophia Reyes

Verified: Jul 07, 2025

Verified by: Ken Davenport

Details

Common Checkered-Skipper
Burnsius communis

Observed: May 12, 2025

Submitted by: Sophia Reyes

Verified: May 31, 2025

Verified by: Ken Davenport

Details

Top 10 Commonly Reported Butterflies and Moths of San Mateo County

Moss' Elfin Callophrys mossii	Upperside of male grayish brown with a tan patch on hindwing inner margin; female light brown to tan with dark borders. Underside coppery brown to purplish brown; inner half of hindwing darker than light outer half.
Ceanothus silkmoth Hyalophora euryalus	Wings are red to brownish red. Areas outside the narrow white postmedian lines are also red to brownish red, but may have black overscaling. Cell spot on the hindwing is shaped like an elongated comma and touches or breaks the postmedian line.
Chalcedon Checkerspot Euphydryas chalcedona	Extremely variable. Forewing narrow. Upperside is black to dark orange-brown with yellow, red, and sometimes white spots. Underside with yellow and orange-red bands.
Boisduval's Blue Plebejus icarioides	Upperside of male lilac-blue with dark borders. Female may be brown, or blue with wide dark borders. Below, black or white postmedian spots are larger on forewing than on hindwing.
Callophrys dumetorum	No tails. Upperside of male gray; female yellowish at least in center of both wings. Underside of forewing gray with extensive blue-green. Underside of hindwing blue-green with complete or much reduced postmedian line of white spots capped with black.
Field Crescent Phyciodes pulchella	Upperside is orange and black. Underside of forewing is yellow-brown with a yellow bar at the cell and small black patches on the inner margin. Underside of hindwing is yellow-brown with rusty markings.
California Sister Adelpha californica	This is a medium to large sized brown-black colored butterfly with a relatively narrow dorsal forewing postdiscal creamy white colored band above with a relatively large orange patch on the forewing. Superficially similar looking above to Lorquin's Admiral (<em>Limenitis lorquini</em>) but can be readily separated by the lower placement of the orange forewing patch and the blue lines on the ventral surface of the wings. Can be difficult to separate from Bredow's Sister (<em>Adelpha bredowii</em>) which does not occur in the U.S. and the Arizona Sister (<em>Adelpha eulalia</em>) which does occur in the U.S. Ranges of <em>californica</em> and <em>eulalia</em> are not known to overlap in the USA. Generally, this species is smaller than <em>eulalia</em>. It is less violet below. The dark and bluish ventral hindwing postdiscal bands are poorly developed, sinuous. There are two basal orange bars on the HW below while <em>eulalia</em> has only one. The blue bar along outer edge of white HW bar is incomplete while <
Echo Azure Celastrina echo	Chalky pale blue gray beneath with small black spots or dashes. Submarginal row of inward pointing triangular marks. Males are a pale chalky blue above.
Coenonympha california
Satyr Comma Polygonia satyrus	Upperside is bright yellow-orange; forewing with two black spots near center of bottom edge; hindwing lacks a dark border, has a black spot in center of wing. Underside is light and dark golden brown, median band relatively straight; hindwing with a silver comma in center.

Butterflies and Moths of North America

collecting and sharing data about Lepidoptera

179 Species Recorded in San Mateo County

100 Most Recent Sightings in San Mateo County

Check out our new Fall 2025 Classic BAMONA Logo Shirts and cozy Native Plants Hoodies!

Please donate!

Advertise with us!

Most Recent Sightings in San Mateo County

Coenonympha california

Common Checkered-Skipper
Burnsius communis

Field Crescent
Phyciodes pulchella

California Sister
Adelpha californica

Cabbage White
Pieris rapae

Small Checkered-Skipper
Pyrgus scriptura

Digrammia delectata

Gray Buckeye
Junonia grisea

Anise Swallowtail
Papilio zelicaon

Field Crescent
Phyciodes pulchella

Echo Azure
Celastrina echo

Common Checkered-Skipper
Burnsius communis

Moss' Elfin
Callophrys mossii

Ceanothus silkmoth
Hyalophora euryalus

Chalcedon Checkerspot
Euphydryas chalcedona

Boisduval's Blue
Plebejus icarioides

Callophrys dumetorum

Field Crescent
Phyciodes pulchella

California Sister
Adelpha californica

Echo Azure
Celastrina echo

Coenonympha california

Satyr Comma
Polygonia satyrus

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Butterflies and Moths of North America

collecting and sharing data about Lepidoptera

Butterflies and Moths of San Mateo County

179 Species Recorded in San Mateo County

100 Most Recent Sightings in San Mateo County

Please donate!

Advertise with us!

Most Recent Sightings in San Mateo County

Common Checkered-SkipperBurnsius communis

Field CrescentPhyciodes pulchella

California SisterAdelpha californica

Cabbage WhitePieris rapae

Small Checkered-SkipperPyrgus scriptura

Gray BuckeyeJunonia grisea

Anise SwallowtailPapilio zelicaon

Field CrescentPhyciodes pulchella

Echo AzureCelastrina echo

Common Checkered-SkipperBurnsius communis

Moss' ElfinCallophrys mossii

Ceanothus silkmothHyalophora euryalus

Chalcedon CheckerspotEuphydryas chalcedona

Boisduval's BluePlebejus icarioides

Field CrescentPhyciodes pulchella

California SisterAdelpha californica

Echo AzureCelastrina echo

Satyr CommaPolygonia satyrus

Common Checkered-Skipper
Burnsius communis

Field Crescent
Phyciodes pulchella

California Sister
Adelpha californica

Cabbage White
Pieris rapae

Small Checkered-Skipper
Pyrgus scriptura

Gray Buckeye
Junonia grisea

Anise Swallowtail
Papilio zelicaon

Field Crescent
Phyciodes pulchella

Echo Azure
Celastrina echo

Common Checkered-Skipper
Burnsius communis

Moss' Elfin
Callophrys mossii

Ceanothus silkmoth
Hyalophora euryalus

Chalcedon Checkerspot
Euphydryas chalcedona

Boisduval's Blue
Plebejus icarioides

Field Crescent
Phyciodes pulchella

California Sister
Adelpha californica

Echo Azure
Celastrina echo

Satyr Comma
Polygonia satyrus