SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cef34f94d8c05984e49694f12a92401f1cfd278ca26d7897e76453095ec590b2' 
  AND token = 'O4VeRDeF4GDsRmhyec8TUo6u5r40G70+l5A8pAW5Fco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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