SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '462a73f68a276d280b519e74bddc462caa4de9d693819330a15f6d66664b1abb' 
  AND token = 'Kssechj7IO9JOw6bPeYWAIYZQifQFXCEJ3/3Ck4w8mw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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