SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3177be0c1366b2d028853656eef37e13f9fc82005ab2bcfb7aeb6087f17c086' 
  AND token = 'wnjI0x67OrSHZRq/UjizrgywKgbRYYoeTCiOYR+nKx0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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