SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30c10cd699d305f241bd09d20a6066ced670dc46056bb0bddb04d0f7d205b36a' 
  AND token = 'NnQU5EgYk/eK750i2UtSXtxXCdCmonvug0nLOjaMyhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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