SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33040ae326ca3e98c1d1cba514b9a749adec0cd8a48ffdcd457b1380719e820f' 
  AND token = 'gAmRJphNnqD6STxwzcdPPcdyIAw+DzWDzb7OyqXctZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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