SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a16a4bfe1efe645f8d8599d1587ade2500fa1d087dc304ade942e638cd2fbfd4' 
  AND token = 'WEBH2P2G0qAAhtu8tWLHKb+00yougxZH2Z1FKXbKJzI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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