SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eac219da500ac19a508d28c1272f0e5c995b4bd0ebb560ec08b08850304a010a' 
  AND token = '6sYj1Dbj3S0RxpRoJMrp6OeHmh+mKlp3r18nEZWMSg0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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