SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c31d87fbe00acbe0fe77ead57da1fedfef68c73ea4148ba15fce27f3e0968ee' 
  AND token = 'ZP65N1N3KkS9uxnCr7IcJCbXwXTylq5RK48QDqyW1w0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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