SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '659696886707571983007c944480256c697114b8cb71c9399e5fb9a8e81b60cf' 
  AND token = 'unBZGpH49gMewPAVHBAETHts/YJKcCvcwfaeolAcqkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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