SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c365f701b9a4ed50b68abdbbe19864a229198b2f3faa382c62a0dd5fc57cc714' 
  AND token = '5fguwOZipa4UXtYkYbNhLPiwjJdV1cicBG26JGvP3I0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}