SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6950c80096c1fb8ebe9c75183cf044cd2863c36ad38ebb22c9a5a0c0c4557e06' 
  AND token = '8L/Kp9mCT6XqynBrXsDl2LnINJRdVACMBouybxY6CN8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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