SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9327ea48a32f036d7dc3820fb871dcd31de52e1e39f61f7013b46f1a713074b' 
  AND token = 'WnnpNzQAE/NNyOfXN+KiwBdkhaYcLrAljOVN8k1N/iM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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