SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e03a6b58a6bb6709f0f674cc64393a501f1a31f58689b4e0b18709b924d965ba' 
  AND token = 'KVxvxpxlFPRwv20BUq8R+CqrQtykIOXCQpJM+txvrl0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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