SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7dcbc406f189362e1dd013cddf0937c3fe56e1fa1111a36fbcd4a63328607827' 
  AND token = 'tF11v6XmolHYDGIm4ELqm9ArYn/PLCWkdxh0czZA0ns=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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