The 31-year-old, who moved to Notts on a free transfer in 2012, has linked up with the Gulls for a month.
The former Nigeria international has also played for Luton Town, Leeds United and Tranmere Rovers during his career.
He could make his Torquay debut when they travel to Hartlepool United on Saturday.
Showunmi has scored four goals in 17 appearances for Notts this season.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Weston-super-MareWeston | 17 | 11 | 4 | 2 | 31 | 15 | 16 | 37 |
| 2 | Truro CityTruro City | 18 | 10 | 4 | 4 | 29 | 16 | 13 | 34 |
| 3 | Eastbourne BoroughEastbourne | 18 | 10 | 4 | 4 | 27 | 22 | 5 | 34 |
| 4 | Dorking WanderersDorking | 20 | 9 | 6 | 5 | 42 | 30 | 12 | 33 |
| 5 | Torquay UnitedTorquay Utd | 18 | 8 | 7 | 3 | 22 | 16 | 6 | 31 |
| 6 | Farnborough TownFarnborough | 18 | 9 | 3 | 6 | 31 | 27 | 4 | 30 |
| 7 | Worthing | 17 | 8 | 5 | 4 | 27 | 28 | -1 | 29 |
| 8 | Slough TownSlough | 18 | 8 | 4 | 6 | 33 | 23 | 10 | 28 |
| 9 | Boreham WoodBoreham Wood | 17 | 7 | 6 | 4 | 25 | 14 | 11 | 27 |
| 10 | Hampton & RichmondHampton | 17 | 7 | 4 | 6 | 24 | 17 | 7 | 25 |
| 11 | Chippenham TownChippenham | 18 | 7 | 4 | 7 | 24 | 19 | 5 | 25 |
| 12 | Chesham UnitedChesham | 15 | 7 | 3 | 5 | 27 | 22 | 5 | 24 |
| 13 | Tonbridge AngelsTonbridge Angels | 15 | 6 | 6 | 3 | 20 | 15 | 5 | 24 |
| 14 | Maidstone UnitedMaidstone | 16 | 5 | 8 | 3 | 20 | 18 | 2 | 23 |
| 15 | AFC HornchurchHornchurch | 17 | 6 | 5 | 6 | 16 | 17 | -1 | 23 |
| 16 | Chelmsford CityChelmsford City | 17 | 5 | 7 | 5 | 28 | 25 | 3 | 22 |
| 17 | Hemel Hempstead TownHemel Hemps. | 20 | 6 | 4 | 10 | 26 | 40 | -14 | 22 |
| 18 | Welling UnitedWelling United | 18 | 6 | 1 | 11 | 19 | 34 | -15 | 19 |
| 19 | Salisbury | 16 | 4 | 5 | 7 | 22 | 27 | -5 | 17 |
| 20 | Bath City | 18 | 4 | 4 | 10 | 13 | 26 | -13 | 16 |
| 21 | Aveley | 18 | 4 | 2 | 12 | 23 | 33 | -10 | 14 |
| 22 | Weymouth | 17 | 2 | 6 | 9 | 11 | 22 | -11 | 12 |
| 23 | St Albans CitySt Albans City | 18 | 2 | 6 | 10 | 19 | 31 | -12 | 12 |
| 24 | Enfield Town | 17 | 3 | 2 | 12 | 16 | 38 | -22 | 11 |
| > National League South Full Table | |||||||||
