SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6a3a64316eae908e69cf3ac8132ad27cdc549047ad95d75991b970387349a07' 
  AND token = 'gnVcazjQvrmWQ/AVmuK1qkr0cbs7KpfY8v3183NVz2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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