SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '406e842b05e6acb82cbb0fd1131eacf1b735ba5e0d923827c705439c884b9184' 
  AND token = 'KzkzfVdeNogvvwqBJlVkgfGmb1pEJsL+hMr83Bl4PRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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