SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc28f1bdd9265c37b75cc778b966de57b899a9eab07eb63473258f62d4bb5cfa' 
  AND token = 'PjPy6ehZVvZKypv4uc9mvpIVlw1TgtT/9wYhpu8ShPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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