SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = '90a061640970f81c8d35efccb7acf1ea8975bbdb7e3222408a4a59a4b436bb27' 
  AND token = '6kwIXlRheHR1tBo3hi5IVwLSTerZqyegVyB/Nlqlrvw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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