SELECT 
  1 
FROM 
  vi_lock_keys 
WHERE 
  key_id = 'f6a7a7e5c9094d122013c46277af7f740eb218a2ddbeee076a159a5aff13611d' 
  AND token = 'VkKpc7UKR87qLqFsaxVgwzuzOvxU7XkxcIUt5SZEtkE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00008

JSON explain

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