SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5729c63a10ae5f00e9a0dbb89869d562c40715c5264d032242eb5b2222c7ab64' 
  AND token = 'YGK1WU3qmY/wgrd53pYMqGxRi0GSMT1B5bwx5Or/KKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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