SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '651f47ee7560673e3a777632bdff2bf45f0823f055bf77830f2cabf90699d7b5' 
  AND token = 'eSdZP4qwEGDLUqI+u8p0nAF17MGaaPcnpGPKNs2PXQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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