SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf681da3240e45eb5bd1cecfcabeb4d748c8d71c1d7090042d4f75ebe77669da' 
  AND token = 'D2LCUG9vYDQQEuUTGSxmEdhhLpzSNJ06Zhp4kMvGAzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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