SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6debedcccf575d1c4218ffe4802cd5ba3db0914e2ee0a1cc1c3639585dfc32f7' 
  AND token = 'gyf6E7FtkzBiQ67/A+Pti1xacQ/qvN/LAuFGtYTTlzc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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