SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d38973ce3371ade5c5aa05ec8c4acb533f162cceda914fa5e47de6d8eded0dc' 
  AND token = 'vryeZZLOviIikv9Mo/r8vPjoAac0yrTpBhA9e/UiBVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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