SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed239bea450e946fa2a1fde3d826824e3d1bfdbe961378860a5e394dd00ada3f' 
  AND token = 'bHY2wOUrbKZL35JLuC+Ap2xxFtus6BcQJwhtu3o20+I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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