SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ed215f0a3fafa489962a9f53bb5995c00dfc8943d0744be59d0c890bcaa5a934' 
  AND token = 'eGbslfxQ/7z8ADw//PjySMHgnWnDEjIQLMWwJooicuo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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