SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f3da09382335a48e7eaa0dd4520dd24903dcd11d0c1be148cdd01150df741a2a' 
  AND token = 'Ik8FeP1YaYBZRPHEBhYckeOKSt+E28O6rEwGBHtqyC8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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