SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f16acb035349fbe8fc48780a865b191b5c9438aaaf65beda56aa6883336233a' 
  AND token = 'HULQE1Aanf//pvNK3hpT+/gZa6/xbxWZCuQR9KWdyU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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