SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '065d2294211b7872d78bad9cb9a5ebb31aba8dfa0bb12303c4a5e51bf6adc887' 
  AND token = '/KMDDwh3H8rNqI+wLwZBdp6yRCo84Gy7FLjFvxXK/qc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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