SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fde10b4223387325c46dcdc5e4aae7ff91fc560a8c859e733378fdadd3443ef' 
  AND token = 'ipXuBnhCT+IiVEwyyjkUgNq2nnIsoLn8G1o0CSpqWZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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