SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cd59fdb1f2569e2bbdff8f04188c65a304192226f2c4d9b2b525c384516d7c3a' 
  AND token = 'hILQZeFBW+X2kZqlFQv7iPHshvLBF2oKEpdZUb5Czoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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