SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59d09c218b528d5523fca93cf0f1000d6a59dc7c6e8fc9b38362c613c2743354' 
  AND token = 'QKVRhxcEOQKOI/KqoYApw6gmloCP1cB0znoGmhK1O98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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