SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc2d752bf62a8a668bdd378a7f342e98a8fa48881db5c93bbbbb3a4047437393' 
  AND token = 'Zwl6/LM61zv6HHZwX8CN0XROfQVVhOKUJhqbVcqyNKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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