SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e34069456e41880ddf908b4109b07f03734c3c241131dcd5c2327c7945f24aa' 
  AND token = 'ct4CZkIgNfWlwO+IhoyDsLg+TBJwszqI3R214ChLhe8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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