SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e33eb856fc1a808bd41b415b51766c75a3f1411fef709f2f58e40848c2b44180' 
  AND token = '3CEVmpAGqIFvrcjhHyPyTVjpIMHdtT9U0QeRJ564TQ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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