SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34c93d436cb2a1706475f419370b38a81c0701bca077fd918a362c1240a7d60f' 
  AND token = 'NtWCw9ZmPtCsETjxBLOPREBfa71CIU207ocV9FYz+vE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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