SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c362a2cabf6665e801b986dcfb5889a92d68be50c74364836f6830018ddd875' 
  AND token = 'GNaXG7GqqjHxEU8+LXOVD8o+Aj958vvm8NhBFoLzVL0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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