SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e74f42459a54d6358dc49093508d3c7f25e4a350cf523cc6b8c3eb43177350ec' 
  AND token = 'jLUpxUaTNElCyDOwsUV7WdchtQKWaWvLLcyi5ucNLr0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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