SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a4df714206bbb7ed3a999a84d11ede6301dc088077c2fb7f3e726fe874a57a7' 
  AND token = 'FgZGhhmzI0qFfF7jM/Yax/z9Va9MwihlhG/6liV5ZzI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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