SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75c77a40c96237e982146e9f6d22e065da1877f9405389546877e5b1b6f45052' 
  AND token = 'y0JXPbcTyu/JmeGvCWT0QiPJqx+3pUGqsm6Etz7ZrKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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