SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf9821959934ffe8920a9de938871f4e0cd07faddf8a23954ea7f14ba19e9905' 
  AND token = 'c7bhGN0XGULLqGDcABAmgndZ1/EJqLXUdIlQnYrNEYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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