SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80ad42374f70932f513f31acc857e3bae4cc7e12167772237d02574b29d23ea5' 
  AND token = 'SCsv8fnlJmHu4rGhX5aUWK+YNzQEJ1GfPQHrbxKCGEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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