SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f4e077acea4b04c0caa556d39ca044fc0e70a78ab258b310118f79df85181bc' 
  AND token = 'i7C/XqyJNDnYRdrlEcMuUMlm6uAz2HBgRABJG2/r7UA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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