SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c523a271b4933e8c774458ac57ab2cd9419806795d5cdc191f53b99f0ed3b08b' 
  AND token = 'WuLmfizJQ5P1cjC0towgiqNl7dVj2y83A8s/8jGhcf0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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