SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd10e79ba60cae7376e40c54574384f2cacaae6ab068befcbca1ef21b6c7bf7a7' 
  AND token = 'TsE6gVgM+2eFdQJmCwbbwM+rqKuuv7hiHBIzg6ItcBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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