SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ec1425f69561cb64a8fe6b83d4f027f26451eca800d4424657c0d230bb957d8' 
  AND token = 'IEB/F+VoAbqVZiZeWogA2k9uT2gqGAVamoJ3PnULYiY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}