SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ac85aaf143d98fbd44bae49bfb52a6dfdd926bebfc48b05d7aa626289830906' 
  AND token = 'yE4tgo0q1Of9bW5Y7Y5F94HvwsEaicTntc9tgGF96GU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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