SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0006a9d1cb1a66a6732a885a1126ba0f20a2ca7a0501a10a853a0286ab4a4e77' 
  AND token = 'pSTBai7axQiUdL1L45anmDSVlTDhNxv/A3n1UrU2dJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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