SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d60c8f39eaeab82de325651947f8b7789fc86affa6477bef6fa301faeae81a9' 
  AND token = '6/Yo+18DO5QWw+hqBOClnS5YKG4Jp+TXKoL6AKRoWq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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