SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b1e6cd414a59e32de6a94f398e73612869bb4cc5f0f104efe761bff17023fe04' 
  AND token = 'hJuG+iiPKdMjvcfVVybMwCDv0Jc7/W4g/+2m5wgHeJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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