SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db901e04d4cae7a466c1801483ff3ec96a64ccafe32250ef12d7f3128c9a34df' 
  AND token = '4Jq+7XIhKL7in89jLDvgZyO0mxKbFS0GBacz7MSvBz4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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