SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6167f0ed285981a70303c367afd0db16fc6f75698c46d7273a3884280244f4b8' 
  AND token = 'pQAMWpSstBsbK+J4eBwL0AJjcEQG41GrqfjKcLtD8tY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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