SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93ee9ce41818e1ca231bb4ef9ae17e23cba921d51994a5a385ba6c27aebe21b4' 
  AND token = 'HefBPatr3DFJeZhiPNEvjjCcaQystsIc8evpqTiX8O8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

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