SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a8ce203fb38d9f469156c0bec9ade8e24793652b14c492f1295e41a766e9509' 
  AND token = '1Rz0Q8888yOA1hMkaJWmoa1B5Ebz0jWzAVo2e0qBt4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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