SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00163f8e2f075b83f6c3eb1b6d6fc224cf117ebe28d2b129c57d054979999f3c' 
  AND token = 'buBjWZbhxFk0Pd/EvQreG4LQAI30IuZ/fZKjXRZn4v0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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