SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f27d67b206119358e5573a2a30da70116269c08bbace70655d766a897230caaf' 
  AND token = 'asqyshOisqofpTk9WGChmF/v8lOLGK1Rw+kqmRHyeUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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