SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05bf23657e462d57d5c45e905c6234584150e9c570a01e87a1f22dc53241ad4c' 
  AND token = '2icDnRMoJQi70dyFBd36J5qHuE9NYvviaoW8RmbWwjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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