SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0a723233495703fe9bf668c92146874eb308be153df7052d07fe337f52f6cb16' 
  AND token = 'z/WNrYJ6CX+rl4W5qT/Gylf7HGd8n3LHi60qVBd1BBE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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