SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1b72d46442bacd8a066dcbc5d8ea20fc6d44b990153ccd7eee6fb08f48881aa' 
  AND token = 'gLuM5I1QTcPo99v0+DASMNnDJsWWQE2jQAdyGWORHR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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