SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3dd452f49579531b935e52a61ba0710242ffd303e35a6ada6c197957fa3a2843' 
  AND token = 'aBkX1Xvjf3OkzUVlIgkXFWtBNRJMJ+o/ZI3vvY8cD08=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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