SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '108aa97f6ffe659d78fb51d797151530a0ccbdbd9bb3c6578eed6098ffe220f0' 
  AND token = 'nwsAwkXOdVE3olc8LoPviU3IxgYedDhq3GzZhdwnuNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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