SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2b3f97bb62fc0ac9e0a1be217317be659e3eacd96c33a4689318ded5a5c88b6' 
  AND token = 'AMcYJREY1BGe0CRfw+Mq8HaVJ0Av0BqE0ZVW85g8LSA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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