SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '51e3d7cbb18c8a4e2561680779e9f69cd5a6cfddbcd4adf46ed16d2c5cc8235b' 
  AND token = 'ZbRoET11mNQsG3x49zrlAOrxSsom12ZQ+/FKgxQQQis=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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