SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab9c92430307dfc0b28be0683a866b1509100f665a7639d3bfe6784c9c6003db' 
  AND token = 'AvoPsUS0c4MO4ZQAA2aUk0G3W2sy6BADDogyuWLvN8Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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