SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d28398b1189e26ed895e622e115182d14497eca531ddcfd458add3d351a52dc' 
  AND token = 'FL/BGUrSukU2425X3ThNARMiOkdSV27l7hNstwq8w9U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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