SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '81b4b286ea44be9d9fb65ee06e1ea96cc5a091d8f36fbd48073c4a719557cf7d' 
  AND token = 'W6lggf/nTiaauZEntvXO2S0mYJlduN3oaXvmyl/bIoA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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