SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4af5741e04b86bf1dcbdea3df228ac63da1dc089422e6bebc90e39fcf827216' 
  AND token = 'huvNxUwwwUFGbM4bqcWGbGE/gxmVnGk7dXKhLJINqdM=' 
  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"
    }
  }
}