SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6380356ccb651099a639158cb235dcac70bb8a84524ca6e7e3ccc5f0de6fd1b' 
  AND token = 'rEMWidQ3a98siJGZupbzr2X2KfYNl7nBkNizDB7CIOo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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