SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b60b8844a74fc4047679b18de21487bd91d728ba9197b630f34b6b1a60bd3268' 
  AND token = 'X3Z/x75JBqP8HxMNAhIEXVowultQCFdPG25N+bm5cRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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