SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '331d95a0c1a2c8252586d90543caf1c4d5a4156e852361466437521f9b88ebbf' 
  AND token = 'HVuFbarnoa7bYgbuBcWrpB8WrvQWXQNMVpwOiTUEyRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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