SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f44ec92bb68ebe9fb95cbec802abd66a616508f129711fd019c112e6adc6987f' 
  AND token = 'kBMj93rrnUe0fhp0e197SiVPlY7/JtPz90q9OQ4Xio4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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