SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cc6bc1ef74cfd2b12790088b2366058f34d6317e9f3dff511cc9b7a9776115aa' 
  AND token = '5mxqLveEG3SsBYa6NMk1gZ3yeOrmWe1twQzP32zTvDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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