SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a5b057a35001d04218124abbce4175eb70e89fa9c35215d7c4ce9bfcef0483d1' 
  AND token = 'BkFmf8jUBfq/u6fv0PUF/MiFGSFPTHhj6FhilD+mhp4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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