SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8b8b56dd6d3c4759ac7ae74fe5a7db2601532185541c661d4b3478cbb4df2521' 
  AND token = 'nAj6AhGTEDPk6+iuCD22LKTgYrLORyqEk/bB09dTvPY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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