SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f65609a2337386e140615334dceccc1db8732adb6dab1ab5c5996936abeac13' 
  AND token = 'ZcK04hS6UXAJiFNtymMsQSysJCFZv/Wodtej24YE3+Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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