SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a2ae8823e243f6e2e21842c15545524b162bedec70d530955252c789c0248913' 
  AND token = 'VkpKnKnWX9kqaku/fgAZSY1WQ8RlWnwiWt6Y+nWh58M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}