SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01c3faad69d39b53bb8a5935669897d9fb8130f79f8d1ff2c0dd82ee9168a1da' 
  AND token = '1cz6kbkziNrE5NpcXCJu26EdAD/KzuQiu+7AiQl6qO0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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