SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2253c0dbba0b7a69805224d7cfda96e1c752a35d5c51f897e8e7139aefccee4d' 
  AND token = 'APCvvkjk6aokOfE8xTjYQDGtU0TZUfaH90tF99T2cYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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