SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d7449b5cbb84a018a7855395e0d7c9b0f2c822707a4369e708d8787474fd886' 
  AND token = 'TlXzQSI9h+WvNUALcxLQVkWVl2RZMPpulm0dT/b/B/o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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