SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8c878b7f762d4bf0d45a01099f2ec9197a8531d424d98b21217823566395da9' 
  AND token = 'EifnN8ahkRd1yu6WhfWfZfxpRJ1k6kWzA3eLjhmitvU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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