SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e11236b721edf6717eae9008eec0da8dd4963dbcc65faecda65af29f597ae73' 
  AND token = 'NzfJOkchRplpg+WpINm4JK1wKzleTl8BBIOrMVkftv8=' 
  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"
    }
  }
}