SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cfd29da655781ca43ce6a1f63379c117ec0bad629919b14f7f7723bb7e7efb26' 
  AND token = 'vZgzI084zhNKWYiZqdrth7mUmqqsOSLsDqoYNu2qz/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}