SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1251d3e10b9204f6b1aa87081f37134f284a5140ea10592aba2fc1b9b7a90b2d' 
  AND token = 'NHMiN9I3bPpkypQV4mMYVSJ5dkdgJ1ZwCAaiIJpD9V0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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