SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f856297adb6f701b8d37a7ecad0276c220568ee7f17835d1c9defbc8110f211' 
  AND token = 'rM2n86Ul/O6l4x5HnONX9z9gSuVqzrHjdzzGYhRmIYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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