SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '41b96f69ac16e545f6049b0f3276b95eebbe72c83c7d0fb0891dd7c6b3c6903e' 
  AND token = 'L2sys6EfjUmIgxLijO9pYj77ZQ2WBwsTuHsZ3bewjIs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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