SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46acce8987c10e7ef24aa7bc02d96c08ac104a4627f0d950cbc4e4e1e32e02cd' 
  AND token = 'DZy1x4zjVSFNADJV7WnfHdo398QmKeurw3QXci6UDW4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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