SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '54660052b86eaf7f41066edcb8f0d7ce4e5b4f6132f5cc3989db5922a4e1c895' 
  AND token = 'gAlsKEc0E3tdPa/wTIDXUf3Unx3sJUKVtNhGnynwjAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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