SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0a151e11ca658b18797c2a12e63d195d5847831c8367de61d72deb9ad4a48b4' 
  AND token = 'S+FKn1k/vKgk8WEXWQ4RkHKvdJyMtJyoiiyuYcUHHdQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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