SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b72e47c580d5c2cd5b8f1cf7584d48a2a2570e1658e84dc669bece6be5d6c6cb' 
  AND token = 'F16XuQpU5aCdC0bf2pzn9g+Ct5ktBPpflkVLVBG3efQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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