Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '347394288300875038e44c3f4da8167c99480ff662959127e2cbe4edbc6a1a92' 
  AND token = 'lmuxTqFeS2Dgxx2yVKuxNybwmV5TXUlv2Pv6KGcvxug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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