SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe32779857404fe5a405e728b25ee5caf4fb65ecf4338ad3448abb3b3074b6ee' 
  AND token = 'tRlPr5yBU70vt9j1LvAyn01BGHE7pzCtvarbtpUYbEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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