SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3123018e740bf0559ddc729cff2cc9c070a564e4641daf4138e3b7f5b86a01a4' 
  AND token = 'SXbKvpbnmLlR6UcAvbKi8Q/qO3QgQX9zgs5cpYNyzSw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}