SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31fc772fbcdd327f44881c55f1ac2c0959c72bb20e872f3adfdc24eaf90e06cd' 
  AND token = 'AyyVFvn6nupjpQt8W+0KH6YExHbZfgXF6xqgSv+Vh68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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