SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '162deac4bcfd16e42493203c71cdd641395095ec85220037659868ec9974dd81' 
  AND token = '21wRZ0oUQkvoF2LZis7RHI37KYNsC8W9pTTQaD3ZCPE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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