SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '438a81419e33cbea2d46e18a96a63d0e05c2c564bac43bddf3b76ebea54c853d' 
  AND token = 'eDSaZjzy8FkHanS5KetgTjZxNu5uUumCKC9zWOwYgYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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