SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = 'd73dcc1258ad721b81b7a877fb92aa215c324e11088e604d0a7405ff6b147743' 
  AND token = 'DCRNDEY5lbGt7fjA94qy0kPIKX+sZXknFp7gbekmVlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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