SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bae1168240b7fba64d1d13723f2e9affa47a0c366804b6adec917ef026e44142' 
  AND token = 'dyLjrxXOE149NBHG1w7FWyYvhte5LklFoTxZLHQuOZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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