SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3ff6a041035d585dc701e21ef4beacec264ccd59007ab88664ebe7a87d3f0488' 
  AND token = '4Z5mR2AtqAYgRcZlOpfJl1JJo3xfPmCL3hY1V9nYXHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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