SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbd2ad7398a11c7d1c87662d1226471f377c6abe34910db74f755ac8ebb70ae8' 
  AND token = 'Y4YrSuw2JWD92qBHjoJfQjW8osgZur8gCR1LXZUOAuQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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