SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f246a7888ff686fcc30b5ee452a1561699e98060a6c1815860f76534e925734c' 
  AND token = '9h5ii/7p4qyV/3Ex/5uCCOHmls6/GQzMZBLJjW0pNGc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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