SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0aad96c10e76f44fb42a39e161528d7af2c8f15e414bd9f179759971170c16e' 
  AND token = 'QAHLf0i6tHEYxPCcODG/dkfu66gaCUwf5y2b3wg6qew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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