Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b451116a92b6c5a1cbc10a248f6eb3b99932b2c4d3d5c41fab0d0b72009d3a1b' 
  AND token = 'u7JbhvdUN4SSssK5uPznHU+hHDuwFhd7yJsFOu3i7XU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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