SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a912b0298596b6461eb517157e69a2b551d332ee2a8e9ce4ee4b4c75133fef5' 
  AND token = 'PuZwmTuJ+Wc04n2xGxoualX62Esm0mFMeoNuqpVyYb0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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