SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e03351ff8146235376cd2e864e0d4e5b2976ef779b2a038c290cbf9fb7b2079e' 
  AND token = 'ZHuB6vWoNwBR2SA/8WhVpjhuLP2h6xL/3S4KrzKolGM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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