SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7cda338b3cb212284d80c3fac9dd99fd279045d67d99bf7839e481c3b75155d6' 
  AND token = '/sMV9nptLSkhVNZQF4gVHuTUpBciWvsWetYKcfBevro=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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