SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7fa918185d51ca50988406b785ef6453623d8a5218cbdd98460de1df74bec6db' 
  AND token = 'CYMy+zEOv/reUv0jCRffsh0NN0QEhG/2u6enYxASjZo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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