SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69229ff7224a164c7d62eda466fed3d309bd1299ee4ab271fc0561cb874f2c25' 
  AND token = '1kFXWedFH1bejew4dfzZOjSlF4cACSbdU4kzwMsplLU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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