SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca35882adaa92f1a23608b11e42d1a9f100382b44a724a3ae87e8e28af119318' 
  AND token = 'BJJsueo/tYD+LdKCRQvq3OWOzI9QROC/0sc/LLU89NA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00069

JSON explain

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