SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b455557cb507a906ae792fc4574f390bdc619b8396febc9196419f185d208893' 
  AND token = 'ohqbnrZhhFQbQEKusFXjVvz9zXi0PbcHhVUdOMkijlQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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