SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20418af99fc879d9bd671fa5024d26b09977aa783549725681c0f19b8771ed45' 
  AND token = 'hVgbDqT0NVHlO/GEAj+vGcxGctgw7MifuRLONW0vK88=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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