SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43759815cc6de1d9a9b0bf9541e38aa85b4f2e6e1387cdf8b83bc059767db62e' 
  AND token = 'pn8Il+5pvbYUC7J0RjVxS0XgFu+v5l8ewEVfkOoPQZ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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