SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce10333740d66e587f281297a4d73067306c9883a9b62c0dd27b7767f1e51a96' 
  AND token = 'BJzP/DkBZT+OsSD29/ivhxDLuPMg2q9R0o6KMm3Svms=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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