SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6c64b5e33167ff3bf33bf023a1de14aa9f0b103345a2e1008d71f54f8930dbff' 
  AND token = 'gijlO83jKMOUpmNY6zDFxpnfKrq6vZQ3T7RTrdwCVns=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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