SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c052783971bb47a48d9d45e8e7715d68e457ca7f6f0d8698a502f4f6c483caaf' 
  AND token = 'APSpFgh5Hb4yDj3ysYJxVYI/hWjH9kOBVg90JdeBqEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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