SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '074419954872890f0cb3dccd88dd8e21ca446c5c74890ebbdde9676500b99f4a' 
  AND token = 'EjPjmXsSkwtTZCp9NCMUTzeCvO4ufetqm4mu9B6nBuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}