SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1470e38a73018c4d161dd5fb1ed9228159e737bcaf860a9452e6a0400a685e6' 
  AND token = 'Ix4UbvxW/nntsHhMYt2Xv7whYRJYRIRwOg7zXnncGTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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