SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99d16cd499efbd474c9e1d9e8409b06a19c882c0a2f7a9a8df58ebe76443625e' 
  AND token = '+t/PA/XmAF7+iV6xkCBPY4hiVBsdIHztiyTzS10rMkM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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