SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ee44bfd8437c558b335c53abd77bad6fb1df81e6b3a800652e2be76864a36a6' 
  AND token = 'Hvy+6jGwYrosXVosX1jAzwuQ9RAZTLGXNPLZ7V65QSs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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