SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4881540033b633f4b4604f08c3e8e99f069eb1ddd90917314639455748d12c5d' 
  AND token = 'snlZBB/s235lczWkjbrrTdPITajFACT0rPhEKRX/pwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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