SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4bd2b5710ff6527d63890c192fba2eaeb905de5cec67f9fa631af9c6145d817' 
  AND token = 'hqSl6gTdm5nuoyvxUCBEjm+6GWnq0lb08yh3/7+Cu8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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