SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d60f634fa5d3c73eed499d59abcfc5e6bb66427bb6bda0ddafbcc076783e69d' 
  AND token = 'ytea1ajeZeFFGrY4bQt8cflsYl6zVXBbJ/XXw/6kO2I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}