SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '108dee37ed65c03ccbedf2dddd2d62a053d627ea04642a0dd219ba82c86dc0b6' 
  AND token = 'iGnchtr+e/DjxALrDQa98qoJsUYGkaKOcyKfb0zGGEM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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