SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd3a7d55c6f8a4246b6171b39e26a7754c50b0f1b8407844ecd194c5a76253faa' 
  AND token = 'Wkh2vj4x5WJTfgD3wqKPEfdQD+JCZ00ykjg+P5+hQ4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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