SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4071c01f67db1d719c1e76a20a072ef02f7e601720819752275e796c10c1b96d' 
  AND token = '3sXoQ5O5MV4fApls0ILUJQ0f68PchRMDRW6LdI7UyfA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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