SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ee79701efcb2511a64d1f0c750753576e039bd30c7ae38938765d9210f64ab2' 
  AND token = 'wNWKGewBBSTzEeb8qdXHzz6FMLcTPRx4kZ1M8ZqGmnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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