Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bce75f2e6ced8a0266286f086189b5f25450fc2268c46b8dd9d252606028b607' 
  AND token = '6FLnizM7481VKvTHnl4bD52xcXcvVLdVOs4KOU+mt0k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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