SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61433f8eb4a80c90d8fd80a64fb704b82b4badce6a00243094e2bac619916fe2' 
  AND token = 'jKbjY1C8Dhh7N+CbEi7WVnCss3yXcygECQvtlfOeMUI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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