SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '467ce5b21719b871f17e2dd93595d58f1d8f307c29e6ecc980178ebd63373fbc' 
  AND token = 'sdccqZmrT/E1Bm8pKWg8IHdC09zvNHL5ZsElddz+tH8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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