SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e30a44357ee2fae667333ebd3131fe4c0faaa0a50c5a6d91c847d6188358250' 
  AND token = 'prh8xT4TOrNcf7ahaRQcOKL7vKlCqkDWB24G7Zq/8E0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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