SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73bd987772001c2043182777f6eea456ef6a58d63207066e3cc38aaf74906dbf' 
  AND token = 'ZBIzoJ1cR3wXlhL9gRQ4cOwxPhYcqTITqxX6BuH0pTM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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