SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '24fc3a0a848c2ebd3dcb45758bbed966d5b65ef0e0b48d79ac6c948702fea290' 
  AND token = 'NbB5BNvx0GNNUfgFoW52Iq7a6okZkdfOdIcmTReddTk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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