SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca5422cc24635f4ea1199051e00952ecd806916e875439204d031088fa5b7237' 
  AND token = 'dYIZDjd33ioev9TJTPRceiPwqfdx6Vznn9nEQilRYRo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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