SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '331155e34357e12ac5aff2473032679c8f1b0fdd7d965b48081b420f3b3b4326' 
  AND token = 'rXJkpBjS5BhB+FvpMJuIy3EJC4HvaX1YL/j58REl8i4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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