SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46b68e48c9be5d77ffd71d47ec7e9960a844e960cab2161dfd34cbf0d741cf5e' 
  AND token = 'EEJPAxxD7DuLPP3LevSfatJo+yGSiIIX+IwxvAn5IK4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}