SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eaf83f10944fc3fbb6760dce90fc32bf14271ba6c8e8ef83612a164286e46798' 
  AND token = 'QXAx9ofzNSvjXnRxcwItP4NLeuTS6Utgo9GnrmPq7xI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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