SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a69f9b770894741b817c76efd7a610f5ce3fb22f27ba74b23ed67db36e44e3ca' 
  AND token = '5cymYbtkOzVgZic5x7izwFWVJb+/s+AvLIkKI+IZR/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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