SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '965b2e54c3fdeea811526379cef8082dd972f107668fbde57d7b20db6f8cb804' 
  AND token = 'Lo3HUUIGHmODl9+fJapvi5+OR466KgA0ppp5gRqPClI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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