SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e19bc2dfc22dbeb1849b5493974e72439234374e7c4ae96c02186182c0bee925' 
  AND token = 'ei32mPVcU+/VE5wbN8Xmj7GikocGWCdySFRRIp2dMc8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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