SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '224fe6fcf72999a253b8d36192b25fabecc9dffec69e1a764698b88c504f5981' 
  AND token = 'vL1g0n5lP8KLHmrC7ONRgvNFjCa2c7uDppFMUZQdnr8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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