SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33705402c61e8c9cb10d91cad28f691862cd583ca659ca793f71fbe33ad4bdd8' 
  AND token = 'dtckwBKfQsLQBhBrtUijqYarXRSO/xNjg/fQCm3UEdU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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