SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7c13bd71ad48769c4fcc2b50eb218ef02e563998c2c4fc68d3772699ad9f187d' 
  AND token = '6wDZOGZJcm2dbGdM+j7iPGGLDGS1B8HmpYBTVRzGheQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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