SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd67220d46975909a75e17ec9456b433ccb9482853e6e03d11e220b2360fc8d6f' 
  AND token = 'SzGNUfKSQYK5rOvimoO3YjrIl3K+o/HPVkfHIPh+U4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}