SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18308b46db0e45efd97bf618998d0cdeda6fbcdefd11025cca8bf81039754146' 
  AND token = 'pjjfjtwa85f4I01MmZDtSD0ZZ62SLUB2HY9cTAy1WmM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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