SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99ac41414431e7d94f0550585ebb64f550d581c061fabfd72de77b6bc4ffcb38' 
  AND token = 'xy3PzX5YAXtSBYgestnvx9EPjomySgM2RUa0obijqiU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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