Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfc4d9d4a27324f4fbc9888c26a4e71ccdf51dede663f0e0aa5ff316ccfc43e2' 
  AND token = 'JUPZdyTasF8Vv4vkI7Vq/6GmtbMjv2bExB+hliRb3a8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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