SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd25918cc0e67b12a6cde6c5e985e3f070c513c85ad1423d4d844b8a473a63856' 
  AND token = 'APIqAvj0fZOkmYUZPhulbZnAvdmM5UkUux5kLTXmcqo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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