SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '454dfe90d515aeb610d124484eae22a646d6352b7ecff6ce4c170552a4ba72fb' 
  AND token = 'zm2pNHRU+ib1XIH4XyQZyDxg8t7uFoU4/oOnw86nlT0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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