SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88de9ac09d393ac4aca907df2592287428637fafdfc6ab7b01e2238aacec2b86' 
  AND token = 'XFILrr/iw9npEAOidmu6zUYPUlruc4Crwp5D3DrcSoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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