SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '012c5d8d848fb2c20b7865b678983b0a3c2397732fd38733a209a3281b0d8fbc' 
  AND token = 'gxkbX2yZz95NRHR6t8KaWHpWP1oKcqNq0EZUsd0wMsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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