SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1e5f314b5ca41f070782df5f5ff469b44d24ef2914c04c422260abe1a1a2c97' 
  AND token = 'BbiqoPnIIqGX0FJt9/pJocaJ67zlIBOwarf1TwXj9oA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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