SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9091282abf84628409bcd29e770375463e7f14bc49b3cce91f2e1e5f3d07d13a' 
  AND token = 'kCIduWGIxZ8zMYMjQV/DPVEq3B/nwPLESvVmJtGnpQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}