SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c679fa684a8db58a1d5602d00e6843ca0f748ce43e1a9d5509555e67a1df177' 
  AND token = 'IzxcBKVGignJCLnic1oNF+jrfN2qxkBCua2ZSGX2hVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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