SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f411e879669c63c3de4c4e3e2978b8e2521103b8f2683773c2f99d4d9d5b473f' 
  AND token = '8zEcEjOZzivEUKLbnhWi2/MO3Btc99agSAriKw79LWg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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