SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afab8dbb1b91ee21d7aeec5440d9ed20435ed277c52b44df9b0f7673791897a6' 
  AND token = 'NsmsqXfVJ1CbKo0ZyMQN1VnkKvO2FaciA32J8BpoEZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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