SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '382ba9074fc581ca5e2fe09534879a5b0148418e7d5d1c454debe1934f643cfe' 
  AND token = '9FMvvSiOKn8X5Gwq8xBQ1aexzsUcnu2VYDxTFWROkKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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