SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '790ef7d1df6e9b88ba31a8f257c02fdff7de201d830db8b69122265193578f39' 
  AND token = 'hMYcCvZvcDwrpf2hpmwY79jtw4rykgEvVfFyUBG0XaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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