SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = '0a9424563df58b69d39774d703c808095fa22564b744f0d2932689e17516337e' 
  AND token = 'Z4hQUp7KL6whvNtY6ySwDslRcLQZQSy/AmoOWEegVIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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