SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6011652951eae660aad6c02a1276ea2cdc96a7d48b851106ca64c583a835534c' 
  AND token = 'M4jpKvifpulp1DAKqLfEBgMB1O9pAtRgprSWCwS6KJ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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