SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18d78ac73118f6137f292a3f18fe6bb663c881bfcd0dc1f7c2758505febe3156' 
  AND token = 'vAiodR4sUnoeG7ZKYrbjCafUDPgopdWS1yxQEhmcZu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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