SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0633d40770294d48b32a5f1dac7da4c80c5c227a1ad9738bf320d04c2098640c' 
  AND token = '78KmUgg94Sso2ZDh1dc5u4mRMGtkfv5T1oVCXpIw1mw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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