SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47c44829f0f7540328aecab86c0a7177f4dddef07f37dec298c3e282fc159f87' 
  AND token = 'egWZXnLZroaLqNU9Fsw5KMURK2lLn89UMGJubmfbO8U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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