SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04464c1004465f9d1f9532b9eb9e5636e5ac7e74d47fb7b17fcbc1de6ab265c6' 
  AND token = '7Hp/PUBm37C6d+AQP67ZOUhf/GnfaxxY1/plBPZulJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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