SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdc93fcbe1288c9d6191469e328989b2382dde1f6983bc14b0ad0d88bbf5e74a' 
  AND token = 'c1RVAw7PmZel4jHLxXVfLXEHiwROnERtZoY7JQoXehs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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