SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b9022e65d869efd055bd934452145ab1c1b7d6416abd022c4ed492478ac35a95' 
  AND token = 'DmZCogXP3SuXCGrrpwcVZ+JWjfcLjAuuXWVz/bVnm6M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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