SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7325e9cddcc4c8312e253e69687f6c3cbebf1c314bc17b835ff4aec5bdbba205' 
  AND token = 'GK/xUp+eqEDPV6xgx0/TxLg/1C9dutGKJoQzVaMchCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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