SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db91752af4e3493157f0fdbaad2eac132c3c1f565295f8515e75b2039b345947' 
  AND token = 'rpmGSvzP/Qf6FMWrR7fmoTV9ga58jZlZ0nZYFCHm53Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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