SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64c87c4b31258d684d8a348aef24f0bf3cefb55c4314cec98549d0b903da1ef2' 
  AND token = 't5wauybzuyq+lyr7s9pyXQpqRXpV7YXxIabUtP1Jlxo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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