SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '22389ebfaaf766359aaa91f03b0e1945936abb7efc839fa2fd672892d023488e' 
  AND token = 'dk3RUeZlKPIf+FW7UAsZ2aCUR8dJdoxIVtNaHxaAKqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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