SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '599533bdc37e23611810ad3bb01161a61b41abfba8ad26c4904a731fa85df521' 
  AND token = 'mEmYomyMp06tHVWaFqbJCMcYuTg5BT22Rr3p+ut5Jrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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