SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f73f0085d02bc7ab86946e303707a5f5503d1140d05db1e278b132b88526ab26' 
  AND token = 'YSqJYE7zVtE+iPtbTcT6W75FjWOg0Daf439IVaBxF5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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