SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fa22001dd21094fb9279e0d97a220c03e93f22b8a3921a667dfde2fd2ab3c22' 
  AND token = 'IUv0Dk64bIeHPpgDcUdqIgHBAZYMs9lAO8iZP6ZuwsM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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