SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47167bf1760b172d70e7090400eb235f0282a73cb70065d3439f6ab5bd7569b1' 
  AND token = 'sGE5FVfsmL4dDiwqcUwpXbsyKGsmdu+jKgZyWUdQ8iw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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