SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13c2d16f7ced75d803f0b9d89d4a9db7913f58ea49702e157fdf13b5c6f0c248' 
  AND token = 'wHojE3y5YVH7B4qvEW0POadQs6HKyDVR0TasTQJdnUE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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