SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '110212a19e37ee1047d2089579976bfd6c8514fc15e4e958dc6050355e377c35' 
  AND token = 'e9S70UsZ415jECcQ6bDkrpoI58kBYKDh79EnU/HPzWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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