SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eab6f2a6a46b8371ad2b48b80240f17590bbbc9d802ef07aa38615250d2770e2' 
  AND token = 'Jh5u8K0xXG+APyHodTajf6sMeZ/K39mnl4ZBIOxpSqw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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