SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd38946d1e8a34d3408ce780c29c55bc66d5775a98a6b8e040ecaabae1f496f4e' 
  AND token = 'AzlG3af/zDGLduqTM+gJWHP/gID0hSz3UNXhlh/JO4Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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