SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '387124cee0d15b99adbf89727fcf842fe09289503caafa1020a09ab3a59ed44d' 
  AND token = 's82ZBwOTZEpUqALovlTdYcrOUPmVA9u8Oaa7/yjfjVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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