SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '313cce233907ac0f1d6132c452686c329dede637859285d3c3e3aca969bc8cc4' 
  AND token = 'OoQiXXSzcZvgaeh3u/5LVDHLTkGBq8kGqepYucOW5Mo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}