SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = '15c9d10eb31d97ce36432a8045eb1699966b074d892ba5d031f27d69d2a59de3' 
  AND token = 'x/KcMx7l+u4quqEaGKg3ZQbkP2Puto+Jlxf4BgQUtIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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