SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '85993ac6c1c57dab5908f774d25ba75f75dbcf8861e0e15f7850530cf14279cf' 
  AND token = 'qFKcRSydB7Dpa0KfMScNAHseFsu//bpgmDEgGVaow/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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