SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ddd60fa715a9b67d6d44bd316dff0ff12bdfb0eb1bb1b9436f41bd269daeef9c' 
  AND token = 'SD2EgVOGQFszTIofTRTXBGEVbiCubYM0j04NBj0cEfM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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