SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac389f4fc203cadb6a5b7219c57d711abc715c093979f6f539088e8f1e5772f3' 
  AND token = '8W7Cc1sIqUVMQEO3TFjmcw7kTQT5cgzPvn6xiDezNuw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00113

JSON explain

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