SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbedec73e390d863d6ae1dffccdf297c3494833cd402d32368c2f37d9b0039ac' 
  AND token = 'm3JOwPQ85mG63+nq//RyFPAdhAYXpXebiFgK0JZlRLM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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