SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36de118be20fb408a5cea796f6bff053e3ebb033875bd86dc9421a0681c5a57c' 
  AND token = 'Cfuato9H0VUXfBn5DmGo+CefqrXKkhbpFu9V52/xkZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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