SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f107fde1ed7dc324c9b666e1352d33086bd2586cb67afc6a2edba81b5b071f6' 
  AND token = 'CQundVFXHI31u6x2gToo44Rw8mkK7Iv9fYCSHIVkKvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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