SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38aa356db7e35456cabc605fb3b943fa2405d7b11205f34d9fb9e155dec44199' 
  AND token = 'wxMtcxCMYmAZdM2BMpHtLmUjh1r/epHqD83cGPdamUA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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