SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d3b00889e967bee3a8349c8084bce5313769b2a6ef45a8741e9869a0fd87969' 
  AND token = 'yoN6dpjOtsvQJIeEtahsntJMEZ9IXCHyrslV6K4LbmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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