SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2aeaf1711c5f95ed5b9df418e46e752dd30107592f2d53f0f404411310bb3bf2' 
  AND token = 'lnysO7BRT1xqZkFfXXlE86yTyvdJL9QcSEbcHnBTpLg=' 
  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"
    }
  }
}