SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aea5ab4fbdff9ac4d2c7f8453327af5f4fea2e48784202a5572c8e5213245a73' 
  AND token = 'BcvDgyAmZYrgjblZwSOUEl6GJRzy4Luz+Uq2lWd8zd8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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