SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cdfa830676c17ede12ba384b83c0915a5cdaa0dbb6672c1be1177f8c38c036e' 
  AND token = 'LKha40m4KpadahrldyG22TIqEhwMhWT5T9tI3TfWVLw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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