SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97ce963f85cf9f5036f012f8e0efd5ea1b4b2d10bcd2afbf419cc16a9b3c361d' 
  AND token = 'GqbEqlApdbhQ+3jNGf7EqzTY8v7Lznu3Z905xU7cdeg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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