SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63b0517d3e5b851b9a56308832b27235559d2431d0992778ed4506d0f7971c9e' 
  AND token = 'gT6xlo7ES4YIfh6VWnvT4XxQgP5FnTS9X5DEX0kfTqc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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