SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9172acc20bc5642d725750a65704c3691fba7e125ef8e840924baed977f92e15' 
  AND token = 'qbutf1VzgsYARHaYv/3/3s/8PkXbOgeDqnvPVm3Gepg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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