SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd77e92cdac788f49fba3952955c6618cb3616397028041423294d821fa95682' 
  AND token = 'ZndWKw+IQZE9R2eCEYtZnBmhvkXxHK6jklM78WobNhY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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