SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a7ca78338fce296e92a4dcd1433ff2791567b70da3dc7bae8265916a30de3e72' 
  AND token = 'DzJjwlXsOtr+/iLTuJTKBnZ4FmsiAg/ZxoiSjFTFkj8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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