SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '834d40d2b9970d442bd3df31cc77a58c280bf83df60ce7454cfb78eaa5c3b7bc' 
  AND token = 'tEfR5Z4SbKvTYtWd4kiG4/AQefcxjc53+yN3oletQ/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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