SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ae41829ae9933db5538dead90d12ce10b25949f5fa4873bb3abc52cf26e5695' 
  AND token = 'uBFPk/iqyigy3qbZGFLlAtGleewsb+QapCFESeX9VQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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