SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bad2f4b9aa2d7161604547f90bae87437c676182897c75180e9bf71374c6dbc' 
  AND token = 'ByhLcNRriXdz5+hlX16k2yJR5+xeRzUFgzv1AWdZpko=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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