SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1895e5f98a77e5250f998ccca73ce46e80fbe414b0dfc5205057696ee2636485' 
  AND token = 'pRIMuaCsOwupJPcnG41MFPjVmMfsiunCfTWim4XAlNU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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