SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b1ea828fb94eb155da5bda0b9ca0a2e748cc98da6998b8cd6df792dae38d23c' 
  AND token = 'KTuQyjxa8eVGWDVX+2GQq5CkmjDNAOWevj7UkK8skXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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