SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efb050c028d1da7518eee1cfc53ce7bb82f0e3c630f889b534fc94153b35212a' 
  AND token = 'NwJcVc4aANKpi8n7Ae5j5QTTvpKrm0KMUF2ak/KUIPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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