SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '13397d7d303a24a3c7bf0bb91907d7894b1241e352ad3f09e02a24bf570afe7c' 
  AND token = 'CE4oLG10iKnVPjyaY4KEmgwEkhZjIZs3yn6yHkdJSU0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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