SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6eda654c49e8d2b45e0957200777b82b491fae289ff16de9b1fb44a73b75af60' 
  AND token = 'q53Y8XGj5mZMXVMZW6JjqMmm0H01uQOCXv5jGM3XvTg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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