SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6b084f28066861277f124d47a4fbdb2f0c02cba6061ebcc49a33d8f8e4f81f62' 
  AND token = 'M54Na+5NrBH6kWqPd2yEM13o9jsm4i0lv5WkI1+nyS4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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