SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '141fde828067471b00818c5b1fd84d13ecdfd96dffe92f957ac4a5afcd3693e2' 
  AND token = 'Mbf9/n+Lg6MObHbJTLgaIdOrX3l2BDjO6ATV7FbSaR8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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