SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b1e3f4e597871bb48a6613df9a881801e3e1af05fc49255596eac8b8bfe5daa' 
  AND token = '5BgaEBaoZqxgsmOxtgt4Cn7KaY4NbNuwCudBTsjXqH4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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