SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3582d4c991fcf3d3ac9f74eb7eb40350b1fc8603d6af9649c298a3f35f53f676' 
  AND token = 'CwVeTVn0B5CMtIZqeymR65jGgVnRfWn3obJkFAOonm4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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