SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9910a6e14b71ec99b4b936be2302b17773689f034ce8337d08e388f97e9d32b8' 
  AND token = '0kHawGyuqo/++1XGwDJLIe7DeICZVL/DIH+DDiDDwNM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}