SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18f3a289f3adda0edccc8e93a103d114af5c58c8859948261b66b6230f69609e' 
  AND token = 'JnP3WPco5VnfdzjCw4OTfY7hs6nDBpJ1GH0lCllOEHA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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