SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd73dae94c6e854f67d78f5dda6cf4f7aedfb54597d1e8692b9085a583364578d' 
  AND token = 'enaLRCf9FHK6aIP74b1G9Nq8StLFI8mhTBm+XEWf/8g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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