SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11c4c8b5b026ff5ba7ab465cc3b2e9bc61689e5c287a55673f19f3a1d8d0dce8' 
  AND token = 'zE4DYnhdosgcx7gjdFt3v3wsO5nuQrzJ9b8Vp5iKrXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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