SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb9054fa3455c83e42e42bc26f44084e9dc52fe229513f74c7a8b5d0539905a2' 
  AND token = 'HUQHKZtaosxLXOIjjVHDzJ1ayBkEiHY/DpjOmn62Hho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00115

JSON explain

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