SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '626c18e90e90601faea361db8b76398724819b876b1f18b4f049d2aa320c7d3f' 
  AND token = 'k2yaZLtEJ5Ej+avUy3GZiFZtrwdlSVLUHR8RvFjPP7E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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