SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f41277088e150ea3632e80c5b8f242b8e5584f445a141189b2602a5f429f319a' 
  AND token = 'unQo9OzY5CEW+wkbkATivO9BjxKXUOG1bpho38ODV/w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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