SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13f059b16eab1733922ceacf8b74ee0f5e18d49f0d6537a34a5d08c4af89fb5c' 
  AND token = 'UcK+81OXp/ZszhF2me9EShrqRJ/FN/8PtlcqtqDrQag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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