SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33220854176e059bc42dd5f1ba3323c33433c059970a33cba9e9273c27670a8d' 
  AND token = '3Ft2oowOWd9Q7KujohJTlXXrR+1NMS15UktgTHuoYVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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