SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a0ebec059cf788e3df36f01c8110f9993546b9ccea41fc67e70e767779c3167' 
  AND token = 'kZ1HDaedfn+hE5dPd0znDUl7QI6cUlBEoXolEWSEM18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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