SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '501676faa03c5301071c606c97ea978263ab362539766d5d76643a07ba1a3639' 
  AND token = 'YJ6j7qdZjdBqS7d8Nmh9s5hPbzG6wS8prAuWPSCvutA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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